objects flowing around in expression evaluation are now TypedValue's - these carry generics info, used for conversions.

git-svn-id: https://src.springframework.org/svn/spring-framework/trunk@925 50f2f4bb-b051-0410-bef5-90022cba6387

org.springframework.context/src/main/java/org/springframework/context/expression/BeanExpressionContextAccessor.java

@@ -17,15 +17,18 @@
 package org.springframework.context.expression;
 
 import org.springframework.beans.factory.config.BeanExpressionContext;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 
 /**
  * EL property accessor that knows how to traverse the beans and contextual objects
  * of a Spring {@link org.springframework.beans.factory.config.BeanExpressionContext}.
  *
  * @author Juergen Hoeller
+ * @author Andy Clement
  * @since 3.0
  */
 public class BeanExpressionContextAccessor implements PropertyAccessor {
@@ -34,8 +37,8 @@ public class BeanExpressionContextAccessor implements PropertyAccessor {
 		return (((BeanExpressionContext) target).containsObject(name));
 	}
 
-	public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-		return ((BeanExpressionContext) target).getObject(name);
+	public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+		return new TypedValue(((BeanExpressionContext) target).getObject(name));
 	}
 
 	public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {

org.springframework.context/src/main/java/org/springframework/context/expression/BeanFactoryAccessor.java

@@ -17,15 +17,18 @@
 package org.springframework.context.expression;
 
 import org.springframework.beans.factory.BeanFactory;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 
 /**
  * EL property accessor that knows how to traverse the beans of a
  * Spring {@link org.springframework.beans.factory.BeanFactory}.
  *
  * @author Juergen Hoeller
+ * @author Andy Clement
  * @since 3.0
  */
 public class BeanFactoryAccessor implements PropertyAccessor {
@@ -34,8 +37,8 @@ public class BeanFactoryAccessor implements PropertyAccessor {
 		return (((BeanFactory) target).containsBean(name));
 	}
 
-	public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-		return ((BeanFactory) target).getBean(name);
+	public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+		return new TypedValue(((BeanFactory) target).getBean(name));
 	}
 
 	public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {

org.springframework.context/src/main/java/org/springframework/context/expression/MapAccessor.java

@@ -21,12 +21,15 @@ import java.util.Map;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
+import org.springframework.expression.spel.ast.CommonTypeDescriptors;
 
 /**
  * EL property accessor that knows how to traverse the keys
  * of a standard {@link java.util.Map}.
  *
  * @author Juergen Hoeller
+ * @author Andy Clement
  * @since 3.0
  */
 public class MapAccessor implements PropertyAccessor {
@@ -35,8 +38,8 @@ public class MapAccessor implements PropertyAccessor {
 		return (((Map) target).containsKey(name));
 	}
 
-	public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-		return ((Map) target).get(name);
+	public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+		return new TypedValue(((Map) target).get(name),CommonTypeDescriptors.OBJECT_TYPE_DESCRIPTOR);
 	}
 
 	public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {

org.springframework.expression/src/main/java/org/springframework/expression/ConstructorExecutor.java

@@ -16,6 +16,7 @@
 
 package org.springframework.expression;
 
+
 // TODO Is the resolver/executor model too pervasive in this package?
 /**
  * Executors are built by resolvers and can be cached by the infrastructure to repeat an operation quickly without going
@@ -39,6 +40,6 @@ public interface ConstructorExecutor {
 	 * @return the new object
 	 * @throws AccessException if there is a problem executing the command or the CommandExecutor is no longer valid
 	 */
-	Object execute(EvaluationContext context, Object... arguments) throws AccessException;
+	TypedValue execute(EvaluationContext context, Object... arguments) throws AccessException;
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/EvaluationContext.java

@@ -35,7 +35,7 @@ public interface EvaluationContext {
 	/**
 	 * @return the root context object against which unqualified properties/methods/etc should be resolved
 	 */
-	Object getRootObject();
+	TypedValue getRootObject();
 
 	/**
 	 * Set a named variable within this execution context to a specified value.

org.springframework.expression/src/main/java/org/springframework/expression/MethodExecutor.java

@@ -39,6 +39,6 @@ public interface MethodExecutor {
 	 * @return the value returned from execution
 	 * @throws AccessException if there is a problem executing the command or the MethodExecutor is no longer valid
 	 */
-	Object execute(EvaluationContext context, Object target, Object... arguments) throws AccessException;
+	TypedValue execute(EvaluationContext context, Object target, Object... arguments) throws AccessException;
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/PropertyAccessor.java

@@ -58,10 +58,10 @@ public interface PropertyAccessor {
 	 * @param context the evaluation context in which the access is being attempted
 	 * @param target the target object upon which the property is being accessed
 	 * @param name the name of the property being accessed
-	 * @return Object the value of the property
+	 * @return a TypedValue object wrapping the property value read and a type descriptor for it
 	 * @throws AccessException if there is any problem accessing the property value
 	 */
-	Object read(EvaluationContext context, Object target, String name) throws AccessException;
+	TypedValue read(EvaluationContext context, Object target, String name) throws AccessException;
 
 	/**
 	 * Called to determine if a resolver instance is able to write to a specified property on a specified target object.

org.springframework.expression/src/main/java/org/springframework/expression/TypedValue.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2002-2009 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.expression;
+
+import org.springframework.core.convert.TypeDescriptor;
+
+/**
+ * Encapsulates an object and a type descriptor that describes it.
+ * The type descriptor can hold generic information that would
+ * not be accessible through a simple getClass() call on the object.
+ * 
+ * @author Andy Clement
+ * @since 3.0
+ */
+public class TypedValue {
+
+	private Object value;
+	private TypeDescriptor typeDescriptor;
+
+	/**
+	 * Create a TypedValue for a simple object.  The type descriptor is inferred 
+	 * from the object, so no generic information is preserved.
+	 * @param value the object value
+	 */
+	public TypedValue(Object value) {
+		this.value = value;
+		this.typeDescriptor = TypeDescriptor.forObject(value);
+	}
+	
+	/**
+	 * Create a TypedValue for a particular value with a particular type descriptor.
+	 * @param value the object value
+	 * @param typeDescriptor a type descriptor describing the type of the value
+	 */
+	public TypedValue(Object value, TypeDescriptor typeDescriptor) {
+		this.value = value;
+		this.typeDescriptor = typeDescriptor;
+	}
+	
+	public Object getValue() {
+		return this.value;
+	}
+	
+	public TypeDescriptor getTypeDescriptor() {
+		return this.typeDescriptor;
+	}
+	
+}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ExpressionState.java

@@ -27,6 +27,7 @@ import org.springframework.expression.Operation;
 import org.springframework.expression.OperatorOverloader;
 import org.springframework.expression.PropertyAccessor;
 import org.springframework.expression.TypeComparator;
+import org.springframework.expression.TypedValue;
 
 /**
  * An ExpressionState is for maintaining per-expression-evaluation state, any changes to it are not seen by other
@@ -45,7 +46,7 @@ public class ExpressionState {
 
 	private final Stack<VariableScope> variableScopes = new Stack<VariableScope>();
 
-	private final Stack<Object> contextObjects = new Stack<Object>();
+	private final Stack<TypedValue> contextObjects = new Stack<TypedValue>();
 
 
 	public ExpressionState() {
@@ -65,14 +66,18 @@ public class ExpressionState {
 	/**
 	 * The active context object is what unqualified references to properties/etc are resolved against.
 	 */
-	public Object getActiveContextObject() {
+	public TypedValue getActiveContextObject() {
 		if (this.contextObjects.isEmpty()) {
-			return this.relatedContext.getRootObject();
+			TypedValue rootObject = this.relatedContext.getRootObject();
+			if (rootObject == null) {
+				return new TypedValue(rootObject,TypeDescriptor.NULL_TYPE_DESCRIPTOR);
+			}
+			return rootObject;
 		}
 		return this.contextObjects.peek();
 	}
 
-	public void pushActiveContextObject(Object obj) {
+	public void pushActiveContextObject(TypedValue obj) {
 		this.contextObjects.push(obj);
 	}
 
@@ -80,7 +85,7 @@ public class ExpressionState {
 		this.contextObjects.pop();
 	}
 
-	public Object getRootContextObject() {
+	public TypedValue getRootContextObject() {
 		return this.relatedContext.getRootObject();
 	}
 
@@ -88,8 +93,9 @@ public class ExpressionState {
 		this.relatedContext.setVariable(name, value);
 	}
 
-	public Object lookupVariable(String name) {
-		return this.relatedContext.lookupVariable(name);
+	public TypedValue lookupVariable(String name) {
+		Object value = this.relatedContext.lookupVariable(name);
+		return new TypedValue(value,TypeDescriptor.valueOf((value==null?null:value.getClass())));
 	}
 
 	public TypeComparator getTypeComparator() {
@@ -103,11 +109,15 @@ public class ExpressionState {
 	public <T> T convertValue(Object value, TypeDescriptor targetTypeDescriptor) throws EvaluationException {
 		return this.relatedContext.getTypeConverter().convertValue(value, targetTypeDescriptor);
 	}
-
-	public <T> T convertValue(Object value, Class<T> targetType) throws EvaluationException {
-		return this.relatedContext.getTypeConverter().convertValue(value, targetType);
+	
+	public <T> T convertValue(TypedValue value, TypeDescriptor targetTypeDescriptor) throws EvaluationException {
+		return this.relatedContext.getTypeConverter().convertValue(value.getValue(), targetTypeDescriptor);
 	}
 
+//	public <T> T convertValue(TypedValue value, Class<T> targetType) throws EvaluationException {
+//		return this.relatedContext.getTypeConverter().convertValue(value, targetType);
+//	}
+
 	/**
 	 * A new scope is entered when a function is invoked
 	 */
@@ -137,10 +147,11 @@ public class ExpressionState {
 		return null;
 	}
 
-	public Object operate(Operation op, Object left, Object right) throws EvaluationException {
+	public TypedValue operate(Operation op, Object left, Object right) throws EvaluationException {
 		OperatorOverloader overloader = this.relatedContext.getOperatorOverloader();
 		if (overloader.overridesOperation(op, left, right)) {
-			return overloader.operate(op, left, right);
+			Object returnValue = overloader.operate(op, left, right);
+			return new TypedValue(returnValue,TypeDescriptor.forObject(returnValue));
 		}
 		else {
 			throw new SpelException(SpelMessages.OPERATOR_NOT_SUPPORTED_BETWEEN_TYPES, op, left, right);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Assign.java

@@ -18,8 +18,9 @@ package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
-import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.SpelException;
 
 /**
  * Represents assignment. An alternative to calling setValue() for an expression is to use an assign.
@@ -36,9 +37,9 @@ public class Assign extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object newValue = getChild(1).getValueInternal(state);
-		getChild(0).setValue(state, newValue);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue newValue = getChild(1).getValueInternal(state);
+		getChild(0).setValue(state, newValue.getValue());
 		return newValue;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/BooleanLiteral.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Represents the literal values TRUE and FALSE.
@@ -26,15 +27,15 @@ import org.antlr.runtime.Token;
  */
 public class BooleanLiteral extends Literal {
 
-	private final Boolean value;
+	private final BooleanTypedValue value;
 
 	public BooleanLiteral(Token payload, boolean value) {
 		super(payload);
-		this.value = value;
+		this.value = BooleanTypedValue.forValue(value);
 	}
 
 	@Override
-	public Boolean getLiteralValue() {
+	public BooleanTypedValue getLiteralValue() {
 		return this.value;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/CommonTypeDescriptors.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2002-2009 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.expression.spel.ast;
+
+import org.springframework.core.convert.TypeDescriptor;
+
+/**
+ * @author Andy Clement
+ * @since 3.0
+ */
+public interface CommonTypeDescriptors {
+    // TODO push into TypeDescriptor?
+	static TypeDescriptor BOOLEAN_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Boolean.class);
+	static TypeDescriptor INTEGER_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Integer.class);
+	static TypeDescriptor CHARACTER_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Character.class);
+	static TypeDescriptor LONG_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Long.class);
+	static TypeDescriptor SHORT_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Short.class);
+	static TypeDescriptor BYTE_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Byte.class);
+	static TypeDescriptor FLOAT_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Float.class);
+	static TypeDescriptor DOUBLE_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Double.class);
+	static TypeDescriptor STRING_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(String.class);
+	static TypeDescriptor CLASS_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Class.class);
+	static TypeDescriptor OBJECT_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Object.class);
+	
+}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/CompoundExpression.java

@@ -18,8 +18,9 @@ package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
-import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.SpelException;
 
 /**
  * Represents a DOT separated expression sequence, such as 'property1.property2.methodOne()'
@@ -40,8 +41,8 @@ public class CompoundExpression extends SpelNodeImpl {
 	 * @return the final value from the last piece of the compound expression
 	 */
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object result = null;
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue result = null;
 		SpelNodeImpl nextNode = null;
 		try {
 			nextNode = getChild(0);
@@ -69,7 +70,7 @@ public class CompoundExpression extends SpelNodeImpl {
 			getChild(0).setValue(state, value);
 			return;
 		}
-		Object ctx = getChild(0).getValueInternal(state);
+		TypedValue ctx = getChild(0).getValueInternal(state);
 		for (int i = 1; i < getChildCount() - 1; i++) {
 			try {
 				state.pushActiveContextObject(ctx);
@@ -91,7 +92,7 @@ public class CompoundExpression extends SpelNodeImpl {
 		if (getChildCount() == 1) {
 			return getChild(0).isWritable(state);
 		}
-		Object ctx = getChild(0).getValueInternal(state);
+		TypedValue ctx = getChild(0).getValueInternal(state);
 		for (int i = 1; i < getChildCount() - 1; i++) {
 			try {
 				state.pushActiveContextObject(ctx);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/ConstructorReference.java

@@ -20,12 +20,13 @@ import java.lang.reflect.Array;
 import java.util.List;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.ConstructorExecutor;
 import org.springframework.expression.ConstructorResolver;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -67,7 +68,7 @@ public class ConstructorReference extends SpelNodeImpl {
 	 * Implements getValue() - delegating to the code for building an array or a simple type.
 	 */
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		if (this.isArrayConstructor) {
 			return createArray(state);
 		}
@@ -123,14 +124,14 @@ public class ConstructorReference extends SpelNodeImpl {
 	 * @return the new array
 	 * @throws EvaluationException if there is a problem creating the array
 	 */
-	private Object createArray(ExpressionState state) throws EvaluationException {
-		Object intendedArrayType = getChild(0).getValueInternal(state);
-		if (!(intendedArrayType instanceof String)) {
+	private TypedValue createArray(ExpressionState state) throws EvaluationException {
+		TypedValue intendedArrayType = getChild(0).getValueInternal(state);
+		if (!(intendedArrayType.getValue() instanceof String)) {
 			throw new SpelException(getChild(0).getCharPositionInLine(),
 					SpelMessages.TYPE_NAME_EXPECTED_FOR_ARRAY_CONSTRUCTION,
 					FormatHelper.formatClassNameForMessage(intendedArrayType.getClass()));
 		}
-		String type = (String) intendedArrayType;
+		String type = (String) intendedArrayType.getValue();
 		Class<?> componentType = null;
 		TypeCode arrayTypeCode = TypeCode.forName(type);
 		if (arrayTypeCode == TypeCode.OBJECT) {
@@ -140,6 +141,7 @@ public class ConstructorReference extends SpelNodeImpl {
 		}
 
 		Object newArray = null;
+		TypeDescriptor newArrayTypeDescriptor = null;
 
 		if (getChild(1).getChildCount() == 0) { // are the array ranks defined?
 			if (getChildCount() < 3) {
@@ -149,13 +151,14 @@ public class ConstructorReference extends SpelNodeImpl {
 			// no array ranks so use the size of the initializer to determine array size
 			int arraySize = getChild(2).getChildCount();
 			newArray = Array.newInstance(componentType, arraySize);
+			newArrayTypeDescriptor = TypeDescriptor.valueOf(newArray.getClass());
 		}
 		else {
 			// Array ranks are specified but is it a single or multiple dimension array?
 			int dimensions = getChild(1).getChildCount();
 			if (dimensions == 1) {
 				Object o = getChild(1).getValueInternal(state);
-				int arraySize = state.convertValue(o, Integer.class);
+				int arraySize = state.convertValue(o, INTEGER_TYPE_DESCRIPTOR);
 				if (getChildCount() == 3) {
 					// Check initializer length matches array size length
 					int initializerLength = getChild(2).getChildCount();
@@ -165,14 +168,16 @@ public class ConstructorReference extends SpelNodeImpl {
 					}
 				}
 				newArray = Array.newInstance(componentType, arraySize);
+				newArrayTypeDescriptor = TypeDescriptor.valueOf(newArray.getClass());
 			}
 			else {
 				// Multi-dimensional - hold onto your hat !
 				int[] dims = new int[dimensions];
 				for (int d = 0; d < dimensions; d++) {
-					dims[d] = state.convertValue(getChild(1).getChild(d).getValueInternal(state), Integer.class);
+					dims[d] = state.convertValue(getChild(1).getChild(d).getValueInternal(state), INTEGER_TYPE_DESCRIPTOR);
 				}
 				newArray = Array.newInstance(componentType, dims);
+				newArrayTypeDescriptor = TypeDescriptor.valueOf(newArray.getClass());
 				// TODO check any specified initializer for the multidim array matches
 			}
 		}
@@ -195,47 +200,47 @@ public class ConstructorReference extends SpelNodeImpl {
 			} else if (arrayTypeCode == TypeCode.INT) {
 				int[] newIntArray = (int[]) newArray;
 				for (int i = 0; i < newIntArray.length; i++) {
-					newIntArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Integer.class);
+					newIntArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), INTEGER_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.BOOLEAN) {
 				boolean[] newBooleanArray = (boolean[]) newArray;
 				for (int i = 0; i < newBooleanArray.length; i++) {
-					newBooleanArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Boolean.class);
+					newBooleanArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), BOOLEAN_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.CHAR) {
 				char[] newCharArray = (char[]) newArray;
 				for (int i = 0; i < newCharArray.length; i++) {
-					newCharArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Character.class);
+					newCharArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), CHARACTER_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.SHORT) {
 				short[] newShortArray = (short[]) newArray;
 				for (int i = 0; i < newShortArray.length; i++) {
-					newShortArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Short.class);
+					newShortArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), SHORT_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.LONG) {
 				long[] newLongArray = (long[]) newArray;
 				for (int i = 0; i < newLongArray.length; i++) {
-					newLongArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Long.class);
+					newLongArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), LONG_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.FLOAT) {
 				float[] newFloatArray = (float[]) newArray;
 				for (int i = 0; i < newFloatArray.length; i++) {
-					newFloatArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Float.class);
+					newFloatArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), FLOAT_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.DOUBLE) {
 				double[] newDoubleArray = (double[]) newArray;
 				for (int i = 0; i < newDoubleArray.length; i++) {
-					newDoubleArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Double.class);
+					newDoubleArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), DOUBLE_TYPE_DESCRIPTOR);
 				}
 			} else if (arrayTypeCode == TypeCode.BYTE) {
 				byte[] newByteArray = (byte[]) newArray;
 				for (int i = 0; i < newByteArray.length; i++) {
-					newByteArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), Byte.class);
+					newByteArray[i] = state.convertValue(initializer.getChild(i).getValueInternal(state), BYTE_TYPE_DESCRIPTOR);
 				}
 			}
 		}
 
-		return newArray;
+		return new TypedValue(newArray, newArrayTypeDescriptor);
 	}
 
 	/**
@@ -244,13 +249,13 @@ public class ConstructorReference extends SpelNodeImpl {
 	 * @return the new object
 	 * @throws EvaluationException if there is a problem creating the object
 	 */
-	private Object createNewInstance(ExpressionState state) throws EvaluationException {
+	private TypedValue createNewInstance(ExpressionState state) throws EvaluationException {
 		Object[] arguments = new Object[getChildCount() - 1];
 		Class<?>[] argumentTypes = new Class[getChildCount() - 1];
 		for (int i = 0; i < arguments.length; i++) {
-			Object childValue = getChild(i + 1).getValueInternal(state);
-			arguments[i] = childValue;
-			argumentTypes[i] = childValue.getClass();
+			TypedValue childValue = getChild(i + 1).getValueInternal(state);
+			arguments[i] = childValue.getValue();
+			argumentTypes[i] = childValue.getValue().getClass();
 		}
 
 		ConstructorExecutor executorToUse = this.cachedExecutor;
@@ -266,7 +271,7 @@ public class ConstructorReference extends SpelNodeImpl {
 		}
 
 		// either there was no accessor or it no longer exists
-		String typename = (String) getChild(0).getValueInternal(state);
+		String typename = (String) getChild(0).getValueInternal(state).getValue();
 		executorToUse = findExecutorForConstructor(typename, argumentTypes, state);
 		try {
 			return executorToUse.execute(state.getEvaluationContext(), arguments);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Dot.java

@@ -17,8 +17,9 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.SpelException;
 
 /**
  * This is used for preserving positional information from the input expression.
@@ -39,7 +40,7 @@ public class Dot extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws SpelException {
+	public TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		// This makes Dot a do-nothing operation, but this is not free in terms of computation
 		return state.getActiveContextObject();
 	}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/EmptySpelNode.java

@@ -17,8 +17,9 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.SpelException;
 
 /**
  * @author Andy Clement
@@ -31,7 +32,7 @@ public class EmptySpelNode extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws SpelException {
+	public TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		throw new RuntimeException("?");
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/FunctionReference.java

@@ -21,9 +21,11 @@ import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.core.MethodParameter;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.TypeConverter;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -53,18 +55,18 @@ public class FunctionReference extends SpelNodeImpl {
 
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object o = state.lookupVariable(name);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue o = state.lookupVariable(name);
 		if (o == null) {
 			throw new SpelException(SpelMessages.FUNCTION_NOT_DEFINED, name);
 		}
 
 		// Two possibilities: a lambda function or a Java static method registered as a function
-		if (!(o instanceof Method)) {
+		if (!(o.getValue() instanceof Method)) {
 			throw new SpelException(SpelMessages.FUNCTION_REFERENCE_CANNOT_BE_INVOKED, name, o.getClass());
 		}
 
-		return executeFunctionJLRMethod(state, (Method) o);
+		return executeFunctionJLRMethod(state, (Method) o.getValue());
 	}
 
 	/**
@@ -75,7 +77,7 @@ public class FunctionReference extends SpelNodeImpl {
 	 * @return the return value of the invoked Java method
 	 * @throws EvaluationException if there is any problem invoking the method
 	 */
-	private Object executeFunctionJLRMethod(ExpressionState state, Method m) throws EvaluationException {
+	private TypedValue executeFunctionJLRMethod(ExpressionState state, Method m) throws EvaluationException {
 		Object[] functionArgs = getArguments(state);
 
 		if (!m.isVarArgs() && m.getParameterTypes().length != functionArgs.length) {
@@ -99,7 +101,7 @@ public class FunctionReference extends SpelNodeImpl {
 		}
 
 		try {
-			return m.invoke(m.getClass(), functionArgs);
+			return new TypedValue(m.invoke(m.getClass(), functionArgs),new TypeDescriptor(new MethodParameter(m,-1)));
 		} catch (IllegalArgumentException e) {
 			throw new SpelException(getCharPositionInLine(), e, SpelMessages.EXCEPTION_DURING_FUNCTION_CALL, name, e
 					.getMessage());
@@ -139,7 +141,7 @@ public class FunctionReference extends SpelNodeImpl {
 		// Compute arguments to the function
 		Object[] arguments = new Object[getChildCount()];
 		for (int i = 0; i < arguments.length; i++) {
-			arguments[i] = getChild(i).getValueInternal(state);
+			arguments[i] = getChild(i).getValueInternal(state).getValue();
 		}
 		return arguments;
 	}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Identifier.java

@@ -17,9 +17,8 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
-import org.springframework.expression.spel.SpelException;
 
 /**
  * @author Andy Clement
@@ -27,20 +26,20 @@ import org.springframework.expression.spel.SpelException;
  */
 public class Identifier extends SpelNodeImpl {
 
-	private final String id;
+	private final TypedValue id;
 
 	public Identifier(Token payload) {
 		super(payload);
-		this.id = payload.getText();
+		this.id = new TypedValue(payload.getText(), STRING_TYPE_DESCRIPTOR);
 	}
 
 	@Override
 	public String toStringAST() {
-		return this.id;
+		return (String)this.id.getValue();
 	}
 
 	@Override
-	public String getValueInternal(ExpressionState state) {
+	public TypedValue getValueInternal(ExpressionState state) {
 		return this.id;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java

@@ -23,6 +23,7 @@ import java.util.Map;
 import org.antlr.runtime.Token;
 import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -43,53 +44,44 @@ public class Indexer extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object ctx = state.getActiveContextObject();
-		Object index = getChild(0).getValueInternal(state);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue context = state.getActiveContextObject();
+		Object targetObject = context.getValue();
+		TypeDescriptor targetObjectTypeDescriptor = context.getTypeDescriptor();
+		TypedValue indexValue =  getChild(0).getValueInternal(state);
+		Object index = indexValue.getValue();
 
 		// Indexing into a Map
-		if (ctx instanceof Map) {
-			return ((Map<?, ?>) ctx).get(index);
+		if (targetObject instanceof Map) {
+			Object possiblyConvertedKey = state.convertValue(indexValue,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getMapKeyType()));
+			Object o = ((Map<?, ?>) targetObject).get(possiblyConvertedKey);
+			return new TypedValue(o,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getMapValueType()));
 		}
 
 		int idx = state.convertValue(index, INTEGER_TYPE_DESCRIPTOR);
 
-		if (ctx.getClass().isArray()) {
-			return accessArrayElement(ctx, idx);
-		} else if (ctx instanceof Collection) {
-			Collection<?> c = (Collection<?>) ctx;
+		if (targetObjectTypeDescriptor.isArray()) {
+			return new TypedValue(accessArrayElement(targetObject, idx),TypeDescriptor.valueOf(targetObjectTypeDescriptor.getElementType()));
+		} else if (targetObjectTypeDescriptor.isCollection()) {
+			Collection<?> c = (Collection<?>) targetObject;
 			if (idx >= c.size()) {
 				throw new SpelException(SpelMessages.COLLECTION_INDEX_OUT_OF_BOUNDS, c.size(), idx);
 			}
 			int pos = 0;
 			for (Object o : c) {
 				if (pos == idx) {
-					return o;
+					return new TypedValue(o,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getElementType()));
 				}
 				pos++;
 			}
-			// } else if (ctx instanceof Map) {
-			// Map<?,?> c = (Map<?,?>) ctx;
-			// // This code would allow a key/value pair to be pulled out by index from a map
-			// if (idx >= c.size()) {
-			// throw new ELException(ELMessages.COLLECTION_INDEX_OUT_OF_BOUNDS,c.size(),idx);
-			// }
-			// Set<?> keys = c.keySet();
-			// int pos = 0;
-			// for (Object k : keys) {
-			// if (pos==idx) {
-			// return new KeyValuePair(k,c.get(k));
-			// }
-			// pos++;
-			// }
-		} else if (ctx instanceof String) {
-			String ctxString = (String) ctx;
+		} else if (targetObject instanceof String) {
+			String ctxString = (String) targetObject;
 			if (idx >= ctxString.length()) {
 				throw new SpelException(SpelMessages.STRING_INDEX_OUT_OF_BOUNDS, ctxString.length(), idx);
 			}
-			return String.valueOf(ctxString.charAt(idx));
+			return new TypedValue(String.valueOf(ctxString.charAt(idx)),STRING_TYPE_DESCRIPTOR);
 		}
-		throw new SpelException(SpelMessages.INDEXING_NOT_SUPPORTED_FOR_TYPE, ctx.getClass().getName());
+		throw new SpelException(SpelMessages.INDEXING_NOT_SUPPORTED_FOR_TYPE, targetObjectTypeDescriptor);
 	}
 
 
@@ -101,27 +93,38 @@ public class Indexer extends SpelNodeImpl {
 	@SuppressWarnings("unchecked")
 	@Override
 	public void setValue(ExpressionState state, Object newValue) throws EvaluationException {
-		Object ctx = state.getActiveContextObject();
-		Object index = getChild(0).getValueInternal(state);
+		TypedValue contextObject = state.getActiveContextObject();
+		Object targetObject = contextObject.getValue();
+		TypeDescriptor targetObjectTypeDescriptor = contextObject.getTypeDescriptor();
+		TypedValue index = getChild(0).getValueInternal(state);
 
 		// Indexing into a Map
-		if (ctx instanceof Map) {
-			((Map) ctx).put(index,newValue); // TODO missing conversion for both index and newValue
+		if (targetObjectTypeDescriptor.isMap()) {
+			Map map = (Map)targetObject;
+			Object possiblyConvertedKey = state.convertValue(index.getValue(),TypeDescriptor.valueOf(targetObjectTypeDescriptor.getMapKeyType()));
+			Object possiblyConvertedValue = state.convertValue(newValue,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getMapValueType()));
+			map.put(possiblyConvertedKey,possiblyConvertedValue);
 			return;
 		}
 
-		int idx = state.convertValue(index, INTEGER_TYPE_DESCRIPTOR);
-
-		if (ctx.getClass().isArray()) {
-			setArrayElement(state, ctx, idx, newValue);
-		} else if (ctx instanceof List) {
-			List<Object> c = (List<Object>) ctx;
+		if (targetObjectTypeDescriptor.isArray()) {
+			int idx = state.convertValue(index, INTEGER_TYPE_DESCRIPTOR);
+			setArrayElement(state, contextObject.getValue(), idx, newValue, targetObjectTypeDescriptor.getElementType());
+		} else if (targetObjectTypeDescriptor.isCollection()) {
+			int idx = state.convertValue(index, INTEGER_TYPE_DESCRIPTOR);
+			Collection c = (Collection) targetObject;
 			if (idx >= c.size()) {
 				throw new SpelException(SpelMessages.COLLECTION_INDEX_OUT_OF_BOUNDS, c.size(), idx);
 			}
-			c.set(idx,newValue); // TODO missing conversion
+			if (targetObject instanceof List) {
+				List list = (List)targetObject;
+				Object possiblyConvertedValue = state.convertValue(newValue,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getElementType()));
+				list.set(idx,possiblyConvertedValue);
+			} else {
+				throw new SpelException(SpelMessages.INDEXING_NOT_SUPPORTED_FOR_TYPE, contextObject.getClass().getName());
+			}
 		} else {
-			throw new SpelException(SpelMessages.INDEXING_NOT_SUPPORTED_FOR_TYPE, ctx.getClass().getName());
+			throw new SpelException(SpelMessages.INDEXING_NOT_SUPPORTED_FOR_TYPE, contextObject.getClass().getName());
 		}
 	}
 	
@@ -138,44 +141,44 @@ public class Indexer extends SpelNodeImpl {
 		return sb.toString();
 	}
 
-	private void setArrayElement(ExpressionState state, Object ctx, int idx, Object newValue) throws EvaluationException {
-		Class<?> arrayComponentType = ctx.getClass().getComponentType();
+	private void setArrayElement(ExpressionState state, Object ctx, int idx, Object newValue, Class clazz) throws EvaluationException {
+		Class<?> arrayComponentType = clazz;
 		if (arrayComponentType == Integer.TYPE) {
 			int[] array = (int[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Integer.class);
+			array[idx] = state.convertValue(newValue, INTEGER_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Boolean.TYPE) {
 			boolean[] array = (boolean[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Boolean.class);
+			array[idx] = state.convertValue(newValue, BOOLEAN_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Character.TYPE) {
 			char[] array = (char[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Character.class);
+			array[idx] = state.convertValue(newValue, CHARACTER_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Long.TYPE) {
 			long[] array = (long[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Long.class);
+			array[idx] = state.convertValue(newValue, LONG_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Short.TYPE) {
 			short[] array = (short[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Short.class);
+			array[idx] = state.convertValue(newValue, SHORT_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Double.TYPE) {
 			double[] array = (double[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Double.class);
+			array[idx] = state.convertValue(newValue, DOUBLE_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Float.TYPE) {
 			float[] array = (float[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Float.class);
+			array[idx] = state.convertValue(newValue, FLOAT_TYPE_DESCRIPTOR);
 		} else if (arrayComponentType == Byte.TYPE) {
 			byte[] array = (byte[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, Byte.class);
+			array[idx] = state.convertValue(newValue, BYTE_TYPE_DESCRIPTOR);
 		} else {
 			Object[] array = (Object[]) ctx;
 			checkAccess(array.length, idx);
-			array[idx] = state.convertValue(newValue, arrayComponentType);
+			array[idx] = state.convertValue(newValue, TypeDescriptor.valueOf(clazz));
 		}		
 	}
 	

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/IntLiteral.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
 
 /**
  * Expression language AST node that represents an integer literal.
@@ -26,15 +27,15 @@ import org.antlr.runtime.Token;
  */
 public class IntLiteral extends Literal {
 
-	private final Integer value;
+	private final TypedValue value;
 
 	IntLiteral(Token payload, int value) {
 		super(payload);
-		this.value = value;
+		this.value = new TypedValue(value, INTEGER_TYPE_DESCRIPTOR);
 	}
 
 	@Override
-	public Integer getLiteralValue() {
+	public TypedValue getLiteralValue() {
 		return this.value;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Literal.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -34,16 +35,16 @@ public abstract class Literal extends SpelNodeImpl {
 		super(payload);
 	}
 
-	public abstract Object getLiteralValue();
+	public abstract TypedValue getLiteralValue();
 
 	@Override
-	public final Object getValueInternal(ExpressionState state) throws SpelException {
+	public final TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		return getLiteralValue();
 	}
 
 	@Override
 	public String toString() {
-		return getLiteralValue().toString();
+		return getLiteralValue().getValue().toString();
 	}
 
 	@Override

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/LongLiteral.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
 
 /**
  * Expression language AST node that represents a long integer literal.
@@ -26,15 +27,15 @@ import org.antlr.runtime.Token;
  */
 public class LongLiteral extends Literal {
 
-	private final Long value;
+	private final TypedValue value;
 
 	LongLiteral(Token payload, long value) {
 		super(payload);
-		this.value = value;
+		this.value = new TypedValue(value, LONG_TYPE_DESCRIPTOR);
 	}
 
 	@Override
-	public Long getLiteralValue() {
+	public TypedValue getLiteralValue() {
 		return this.value;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/MethodReference.java

@@ -19,12 +19,12 @@ package org.springframework.expression.spel.ast;
 import java.util.List;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.MethodExecutor;
 import org.springframework.expression.MethodResolver;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -48,11 +48,11 @@ public class MethodReference extends SpelNodeImpl {
 
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object currentContext = state.getActiveContextObject();
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue currentContext = state.getActiveContextObject();
 		Object[] arguments = new Object[getChildCount()];
 		for (int i = 0; i < arguments.length; i++) {
-			arguments[i] = getChild(i).getValueInternal(state);
+			arguments[i] = getChild(i).getValueInternal(state).getValue();
 		}
 		if (currentContext == null) {
 			throw new SpelException(getCharPositionInLine(), SpelMessages.ATTEMPTED_METHOD_CALL_ON_NULL_CONTEXT_OBJECT,
@@ -63,7 +63,7 @@ public class MethodReference extends SpelNodeImpl {
 		if (executorToUse != null) {
 			try {
 				return executorToUse.execute(
-						state.getEvaluationContext(), state.getActiveContextObject(), arguments);
+						state.getEvaluationContext(), state.getActiveContextObject().getValue(), arguments);
 			}
 			catch (AccessException ae) {
 				// this is OK - it may have gone stale due to a class change,
@@ -77,7 +77,7 @@ public class MethodReference extends SpelNodeImpl {
 		this.cachedExecutor = executorToUse;
 		try {
 			return executorToUse.execute(
-					state.getEvaluationContext(), state.getActiveContextObject(), arguments);
+					state.getEvaluationContext(), state.getActiveContextObject().getValue(), arguments);
 		}
 		catch (AccessException ae) {
 			throw new SpelException(getCharPositionInLine(), ae, SpelMessages.EXCEPTION_DURING_METHOD_INVOCATION,
@@ -139,7 +139,8 @@ public class MethodReference extends SpelNodeImpl {
 	protected MethodExecutor findAccessorForMethod(String name, Class<?>[] argumentTypes, ExpressionState state)
 			throws SpelException {
 
-		Object contextObject = state.getActiveContextObject();
+		TypedValue context = state.getActiveContextObject();
+		Object contextObject = context.getValue();
 		EvaluationContext eContext = state.getEvaluationContext();
 		if (contextObject == null) {
 			throw new SpelException(SpelMessages.ATTEMPTED_METHOD_CALL_ON_NULL_CONTEXT_OBJECT,

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/NullLiteral.java

@@ -17,6 +17,8 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.expression.TypedValue;
 
 /**
  * @author Andy Clement
@@ -24,13 +26,15 @@ import org.antlr.runtime.Token;
  */
 public class NullLiteral extends Literal {
 
+    private static final TypedValue NULL_TYPED_VALUE = new TypedValue(null,TypeDescriptor.NULL_TYPE_DESCRIPTOR);
+    
 	public NullLiteral(Token payload) {
 		super(payload);
 	}
 
 	@Override
-	public String getLiteralValue() {
-		return null;
+	public TypedValue getLiteralValue() {
+		return NULL_TYPED_VALUE;
 	}
 
 	@Override

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorAnd.java

@@ -18,8 +18,10 @@ package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Represents the boolean AND operation.
@@ -39,7 +41,7 @@ public class OperatorAnd extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		boolean leftValue;
 		boolean rightValue;
 
@@ -52,7 +54,7 @@ public class OperatorAnd extends Operator {
 		}
 
 		if (leftValue == false) {
-			return false; // no need to evaluate right operand
+			return BooleanTypedValue.forValue(false); // no need to evaluate right operand
 		}
 
 		try {
@@ -63,7 +65,7 @@ public class OperatorAnd extends Operator {
 			throw ee;
 		}
 
-		return /* leftValue && */rightValue;
+		return /* leftValue && */BooleanTypedValue.forValue(rightValue);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorBetween.java

@@ -24,6 +24,7 @@ import org.springframework.expression.TypeComparator;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Represents the between operator. The left operand to between must be a single value and the right operand must be a
@@ -52,9 +53,9 @@ public class OperatorBetween extends Operator {
 	 * @throws EvaluationException if there is a problem evaluating the expression
 	 */
 	@Override
-	public Boolean getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (!(right instanceof List) || ((List<?>) right).size() != 2) {
 			throw new SpelException(getRightOperand().getCharPositionInLine(),
 					SpelMessages.BETWEEN_RIGHT_OPERAND_MUST_BE_TWO_ELEMENT_LIST);
@@ -64,7 +65,7 @@ public class OperatorBetween extends Operator {
 		Object high = l.get(1);
 		TypeComparator comparator = state.getTypeComparator();
 		try {
-			return (comparator.compare(left, low) >= 0 && comparator.compare(left, high) <= 0);
+			return BooleanTypedValue.forValue((comparator.compare(left, low) >= 0 && comparator.compare(left, high) <= 0));
 		} catch (SpelException ex) {
 			ex.setPosition(getCharPositionInLine());
 			throw ex;

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorDivide.java

@@ -17,8 +17,10 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Operation;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 
 /**
@@ -39,26 +41,22 @@ public class OperatorDivide extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object operandOne = getLeftOperand().getValueInternal(state);
-		Object operandTwo = getRightOperand().getValueInternal(state);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object operandOne = getLeftOperand().getValueInternal(state).getValue();
+		Object operandTwo = getRightOperand().getValueInternal(state).getValue();
 		if (operandOne instanceof Number && operandTwo instanceof Number) {
 			Number op1 = (Number) operandOne;
 			Number op2 = (Number) operandTwo;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() / op2.doubleValue();
-			}
-			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() / op2.floatValue();
-			}
-			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() / op2.longValue();
-			}
-			else { // TODO what about non-int result of the division?
-				return op1.intValue() / op2.intValue();
+				return new TypedValue(op1.doubleValue() / op2.doubleValue(), DOUBLE_TYPE_DESCRIPTOR);
+			} else if (op1 instanceof Long || op2 instanceof Long) {
+				return new TypedValue(op1.longValue() / op2.longValue(), LONG_TYPE_DESCRIPTOR);
+			} else { // TODO what about non-int result of the division?
+				return new TypedValue(op1.intValue() / op2.intValue(), INTEGER_TYPE_DESCRIPTOR);
 			}
 		}
-		return state.operate(Operation.DIVIDE, operandOne, operandTwo);
+		Object result = state.operate(Operation.DIVIDE, operandOne, operandTwo);
+		return new TypedValue(result,TypeDescriptor.forObject(result));
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorEquality.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements equality operator.
@@ -38,26 +39,21 @@ public class OperatorEquality extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() == op2.doubleValue();
-			}
-			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() == op2.floatValue();
-			}
-			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() == op2.longValue();
-			}
-			else {
-				return op1.intValue() == op2.intValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() == op2.doubleValue());
+			} else if (op1 instanceof Long || op2 instanceof Long) {
+				return BooleanTypedValue.forValue(op1.longValue() == op2.longValue());
+			} else {
+				return BooleanTypedValue.forValue(op1.intValue() == op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) == 0;
+		return BooleanTypedValue.forValue(state.getTypeComparator().compare(left, right) == 0);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorGreaterThan.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements greater-than operator.
@@ -38,26 +39,26 @@ public class OperatorGreaterThan extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() > op2.doubleValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() > op2.doubleValue());
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() > op2.floatValue();
+				return BooleanTypedValue.forValue(op1.floatValue() > op2.floatValue());
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() > op2.longValue();
+				return BooleanTypedValue.forValue(op1.longValue() > op2.longValue());
 			}
 			else {
-				return op1.intValue() > op2.intValue();
+				return BooleanTypedValue.forValue(op1.intValue() > op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) > 0;
+		return BooleanTypedValue.forValue(state.getTypeComparator().compare(left, right) > 0);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorGreaterThanOrEqual.java

@@ -13,12 +13,12 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements greater-than-or-equal operator.
@@ -38,26 +38,26 @@ public class OperatorGreaterThanOrEqual extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() >= op2.doubleValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() >= op2.doubleValue());
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() >= op2.floatValue();
+				return BooleanTypedValue.forValue(op1.floatValue() >= op2.floatValue());
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() >= op2.longValue();
+				return BooleanTypedValue.forValue( op1.longValue() >= op2.longValue());
 			}
 			else {
-				return op1.intValue() >= op2.intValue();
+				return BooleanTypedValue.forValue(op1.intValue() >= op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) >= 0;
+		return BooleanTypedValue.forValue(state.getTypeComparator().compare(left, right) >= 0);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorInequality.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements the not-equal operator.
@@ -38,26 +39,21 @@ public class OperatorInequality extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() != op2.doubleValue();
-			}
-			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() != op2.floatValue();
-			}
-			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() != op2.longValue();
-			}
-			else {
-				return op1.intValue() != op2.intValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() != op2.doubleValue());
+			} else if (op1 instanceof Long || op2 instanceof Long) {
+				return BooleanTypedValue.forValue(op1.longValue() != op2.longValue());
+			} else {
+				return BooleanTypedValue.forValue(op1.intValue() != op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) != 0;
+		return BooleanTypedValue.forValue(state.getTypeComparator().compare(left, right) != 0);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorInstanceof.java

@@ -17,11 +17,12 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * The operator 'instanceof' checks if an object is of the class specified in the right hand operand,
@@ -49,19 +50,21 @@ public class OperatorInstanceof extends Operator {
 	 * @throws EvaluationException if there is a problem evaluating the expression
 	 */
 	@Override
-	public Boolean getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
-		if (left == null) {
-			return false;  // null is not an instanceof anything
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue left = getLeftOperand().getValueInternal(state);
+		TypedValue right = getRightOperand().getValueInternal(state);
+		Object leftValue = left.getValue();
+		Object rightValue = right.getValue();
+		if (leftValue == null) {
+			return BooleanTypedValue.False;  // null is not an instanceof anything
 		}
-		if (right == null || !(right instanceof Class<?>)) {
+		if (rightValue == null || !(rightValue instanceof Class<?>)) {
 			throw new SpelException(getRightOperand().getCharPositionInLine(),
 					SpelMessages.INSTANCEOF_OPERATOR_NEEDS_CLASS_OPERAND,
-					(right == null ? "null" : right.getClass().getName()));
+					(rightValue == null ? "null" : rightValue.getClass().getName()));
 		}
-		Class<?> rightClass = (Class<?>) right;
-		return rightClass.isAssignableFrom(left.getClass());
+		Class<?> rightClass = (Class<?>) rightValue;
+		return BooleanTypedValue.forValue(rightClass.isAssignableFrom(leftValue.getClass()));
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorLessThan.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements the less-than operator.
@@ -38,26 +39,26 @@ public class OperatorLessThan extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() < op2.doubleValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() < op2.doubleValue());
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() < op2.floatValue();
+				return BooleanTypedValue.forValue(op1.floatValue() < op2.floatValue());
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() < op2.longValue();
+				return BooleanTypedValue.forValue(op1.longValue() < op2.longValue());
 			}
 			else {
-				return op1.intValue() < op2.intValue();
+				return BooleanTypedValue.forValue(op1.intValue() < op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) < 0;
+		return BooleanTypedValue.forValue(state.getTypeComparator().compare(left, right) < 0);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorLessThanOrEqual.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements the less-than-or-equal operator.
@@ -33,26 +34,26 @@ public class OperatorLessThanOrEqual extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object left = getLeftOperand().getValueInternal(state);
-		Object right = getRightOperand().getValueInternal(state);
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object left = getLeftOperand().getValueInternal(state).getValue();
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		if (left instanceof Number && right instanceof Number) {
 			Number op1 = (Number) left;
 			Number op2 = (Number) right;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() <= op2.doubleValue();
+				return BooleanTypedValue.forValue(op1.doubleValue() <= op2.doubleValue());
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() <= op2.floatValue();
+				return BooleanTypedValue.forValue(op1.floatValue() <= op2.floatValue());
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() <= op2.longValue();
+				return BooleanTypedValue.forValue(op1.longValue() <= op2.longValue());
 			}
 			else {
-				return op1.intValue() <= op2.intValue();
+				return BooleanTypedValue.forValue(op1.intValue() <= op2.intValue());
 			}
 		}
-		return state.getTypeComparator().compare(left, right) <= 0;
+		return BooleanTypedValue.forValue( state.getTypeComparator().compare(left, right) <= 0);
 	}
 
 	@Override

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorMatches.java

@@ -25,6 +25,7 @@ import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Implements the matches operator. Matches takes two operands. The first is a string and the second is a java regex. It
@@ -51,11 +52,11 @@ public class OperatorMatches extends Operator {
 	 * @throws EvaluationException if there is a problem evaluating the expression (e.g. the regex is invalid)
 	 */
 	@Override
-	public Boolean getValueInternal(ExpressionState state) throws EvaluationException {
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		SpelNodeImpl leftOp = getLeftOperand();
 		SpelNodeImpl rightOp = getRightOperand();
 		Object left = leftOp.getValue(state, String.class);
-		Object right = getRightOperand().getValueInternal(state);
+		Object right = getRightOperand().getValueInternal(state).getValue();
 		try {
 			if (!(left instanceof String)) {
 				throw new SpelException(leftOp.getCharPositionInLine(),
@@ -67,7 +68,7 @@ public class OperatorMatches extends Operator {
 			}
 			Pattern pattern = Pattern.compile((String) right);
 			Matcher matcher = pattern.matcher((String) left);
-			return matcher.matches();
+			return BooleanTypedValue.forValue(matcher.matches());
 		}
 		catch (PatternSyntaxException pse) {
 			throw new SpelException(rightOp.getCharPositionInLine(), pse, SpelMessages.INVALID_PATTERN, right);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorMinus.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Operation;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -49,45 +50,45 @@ public class OperatorMinus extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		SpelNodeImpl leftOp = getLeftOperand();
 		SpelNodeImpl rightOp = getRightOperand();
 		if (rightOp == null) {// If only one operand, then this is unary minus
-			Object left = leftOp.getValueInternal(state);
+			Object left = leftOp.getValueInternal(state).getValue();
 			if (left instanceof Number) {
 				Number n = (Number) left;
 				if (left instanceof Double) {
-					return 0 - n.doubleValue();
+					return new TypedValue(0 - n.doubleValue(),DOUBLE_TYPE_DESCRIPTOR);
 				}
 				else if (left instanceof Float) {
-					return 0 - n.floatValue();
+					return new TypedValue(0 - n.floatValue(),FLOAT_TYPE_DESCRIPTOR);
 				}
 				else if (left instanceof Long) {
-					return 0 - n.longValue();
+					return new TypedValue(0 - n.longValue(),LONG_TYPE_DESCRIPTOR);
 				}
 				else {
-					return 0 - n.intValue();
+					return new TypedValue(0 - n.intValue(),INTEGER_TYPE_DESCRIPTOR);
 				}
 			}
 			throw new SpelException(SpelMessages.CANNOT_NEGATE_TYPE, left.getClass().getName());
 		}
 		else {
-			Object left = leftOp.getValueInternal(state);
-			Object right = rightOp.getValueInternal(state);
+			Object left = leftOp.getValueInternal(state).getValue();
+			Object right = rightOp.getValueInternal(state).getValue();
 			if (left instanceof Number && right instanceof Number) {
 				Number op1 = (Number) left;
 				Number op2 = (Number) right;
 				if (op1 instanceof Double || op2 instanceof Double) {
-					return op1.doubleValue() - op2.doubleValue();
+					return new TypedValue(op1.doubleValue() - op2.doubleValue(),DOUBLE_TYPE_DESCRIPTOR);
 				}
 				else if (op1 instanceof Float || op2 instanceof Float) {
-					return op1.floatValue() - op2.floatValue();
+					return new TypedValue(op1.floatValue() - op2.floatValue(),FLOAT_TYPE_DESCRIPTOR);
 				}
 				else if (op1 instanceof Long || op2 instanceof Long) {
-					return op1.longValue() - op2.longValue();
+					return new TypedValue(op1.longValue() - op2.longValue(),LONG_TYPE_DESCRIPTOR);
 				}
 				else {
-					return op1.intValue() - op2.intValue();
+					return new TypedValue(op1.intValue() - op2.intValue(),INTEGER_TYPE_DESCRIPTOR);
 				}
 			}
 			return state.operate(Operation.SUBTRACT, left, right);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorModulus.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Operation;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 
 /**
@@ -39,23 +40,23 @@ public class OperatorModulus extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object operandOne = getLeftOperand().getValueInternal(state);
-		Object operandTwo = getRightOperand().getValueInternal(state);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object operandOne = getLeftOperand().getValueInternal(state).getValue();
+		Object operandTwo = getRightOperand().getValueInternal(state).getValue();
 		if (operandOne instanceof Number && operandTwo instanceof Number) {
 			Number op1 = (Number) operandOne;
 			Number op2 = (Number) operandTwo;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() % op2.doubleValue();
+				return new TypedValue(op1.doubleValue() % op2.doubleValue(),DOUBLE_TYPE_DESCRIPTOR);
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() % op2.floatValue();
+				return new TypedValue(op1.floatValue() % op2.floatValue(),FLOAT_TYPE_DESCRIPTOR);
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() % op2.longValue();
+				return new TypedValue(op1.longValue() % op2.longValue(),LONG_TYPE_DESCRIPTOR);
 			}
 			else {
-				return op1.intValue() % op2.intValue();
+				return new TypedValue(op1.intValue() % op2.intValue(),INTEGER_TYPE_DESCRIPTOR);
 			}
 		}
 		return state.operate(Operation.MODULUS, operandOne, operandTwo);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorMultiply.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Operation;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 
 /**
@@ -50,23 +51,23 @@ public class OperatorMultiply extends Operator {
 	 * </ul>
 	 */
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object operandOne = getLeftOperand().getValueInternal(state);
-		Object operandTwo = getRightOperand().getValueInternal(state);
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		Object operandOne = getLeftOperand().getValueInternal(state).getValue();
+		Object operandTwo = getRightOperand().getValueInternal(state).getValue();
 		if (operandOne instanceof Number && operandTwo instanceof Number) {
 			Number op1 = (Number) operandOne;
 			Number op2 = (Number) operandTwo;
 			if (op1 instanceof Double || op2 instanceof Double) {
-				return op1.doubleValue() * op2.doubleValue();
+				return new TypedValue(op1.doubleValue() * op2.doubleValue(),DOUBLE_TYPE_DESCRIPTOR);
 			}
 			else if (op1 instanceof Float || op2 instanceof Float) {
-				return op1.floatValue() * op2.floatValue();
+				return new TypedValue(op1.floatValue() * op2.floatValue(),FLOAT_TYPE_DESCRIPTOR);
 			}
 			else if (op1 instanceof Long || op2 instanceof Long) {
-				return op1.longValue() * op2.longValue();
+				return new TypedValue(op1.longValue() * op2.longValue(),LONG_TYPE_DESCRIPTOR);
 			}
 			else {
-				return op1.intValue() * op2.intValue();
+				return new TypedValue(op1.intValue() * op2.intValue(),INTEGER_TYPE_DESCRIPTOR);
 			}
 		}
 		else if (operandOne instanceof String && operandTwo instanceof Integer) {
@@ -75,7 +76,7 @@ public class OperatorMultiply extends Operator {
 			for (int i = 0; i < repeats; i++) {
 				result.append(operandOne);
 			}
-			return result.toString();
+			return new TypedValue(result.toString(),STRING_TYPE_DESCRIPTOR);
 		}
 		return state.operate(Operation.MULTIPLY, operandOne, operandTwo);
 	}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorNot.java

@@ -20,6 +20,7 @@ import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Represents a NOT operation.
@@ -34,10 +35,10 @@ public class OperatorNot extends SpelNodeImpl { // Not is a unary operator so do
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		try {
 			boolean value = state.convertValue(getChild(0).getValueInternal(state), BOOLEAN_TYPE_DESCRIPTOR);
-			return !value;
+			return BooleanTypedValue.forValue(!value);
 		}
 		catch (SpelException see) {
 			see.setPosition(getChild(0).getCharPositionInLine());

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorOr.java

@@ -20,6 +20,7 @@ import org.antlr.runtime.Token;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
+import org.springframework.expression.spel.support.BooleanTypedValue;
 
 /**
  * Represents the boolean OR operation.
@@ -39,7 +40,7 @@ public class OperatorOr extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public BooleanTypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		boolean leftValue;
 		boolean rightValue;
 		try {
@@ -51,7 +52,7 @@ public class OperatorOr extends Operator {
 		}
 
 		if (leftValue == true) {
-			return true; // no need to evaluate right operand
+			return BooleanTypedValue.True; // no need to evaluate right operand
 		}
 
 		try {
@@ -62,7 +63,7 @@ public class OperatorOr extends Operator {
 			throw see;
 		}
 
-		return leftValue || rightValue;
+		return BooleanTypedValue.forValue(leftValue || rightValue);
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/OperatorPlus.java

@@ -17,9 +17,9 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Operation;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 
 /**
@@ -33,46 +33,46 @@ public class OperatorPlus extends Operator {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		SpelNodeImpl leftOp = getLeftOperand();
 		SpelNodeImpl rightOp = getRightOperand();
 		if (rightOp == null) { // If only one operand, then this is unary plus
-			Object operandOne = leftOp.getValueInternal(state);
+			Object operandOne = leftOp.getValueInternal(state).getValue();
 			if (operandOne instanceof Number) {
-				return ((Number) operandOne).intValue();
+				return new TypedValue(((Number) operandOne).intValue(),INTEGER_TYPE_DESCRIPTOR);
 			}
 			return state.operate(Operation.ADD, operandOne, null);
 		}
 		else {
-			Object operandOne = leftOp.getValueInternal(state);
-			Object operandTwo = rightOp.getValueInternal(state);
+			Object operandOne = leftOp.getValueInternal(state).getValue();
+			Object operandTwo = rightOp.getValueInternal(state).getValue();
 			if (operandOne instanceof Number && operandTwo instanceof Number) {
 				Number op1 = (Number) operandOne;
 				Number op2 = (Number) operandTwo;
 				if (op1 instanceof Double || op2 instanceof Double) {
-					return op1.doubleValue() + op2.doubleValue();
+					return new TypedValue(op1.doubleValue() + op2.doubleValue(),DOUBLE_TYPE_DESCRIPTOR);
 				}
 				else if (op1 instanceof Float || op2 instanceof Float) {
-					return op1.floatValue() + op2.floatValue();
+					return new TypedValue(op1.floatValue() + op2.floatValue(),FLOAT_TYPE_DESCRIPTOR);
 				}
 				else if (op1 instanceof Long || op2 instanceof Long) {
-					return op1.longValue() + op2.longValue();
+					return new TypedValue(op1.longValue() + op2.longValue(),LONG_TYPE_DESCRIPTOR);
 				}
 				else { // TODO what about overflow?
-					return op1.intValue() + op2.intValue();
+					return new TypedValue(op1.intValue() + op2.intValue(),INTEGER_TYPE_DESCRIPTOR);
 				}
 			}
 			else if (operandOne instanceof String && operandTwo instanceof String) {
-				return new StringBuilder((String) operandOne).append((String) operandTwo).toString();
+				return new TypedValue(new StringBuilder((String) operandOne).append((String) operandTwo).toString(),STRING_TYPE_DESCRIPTOR);
 			}
 			else if (operandOne instanceof String && operandTwo instanceof Integer) {
 				String l = (String) operandOne;
 				Integer i = (Integer) operandTwo;
 				// implements character + int (ie. a + 1 = b)
 				if (l.length() == 1) {
-					return Character.toString((char) (l.charAt(0) + i));
+					return new TypedValue(Character.toString((char) (l.charAt(0) + i)),STRING_TYPE_DESCRIPTOR);
 				}
-				return new StringBuilder(l).append(i).toString();
+				return  new TypedValue(new StringBuilder(l).append(i).toString(),STRING_TYPE_DESCRIPTOR);
 			}
 			return state.operate(Operation.ADD, operandOne, operandTwo);
 		}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Placeholder.java

@@ -17,9 +17,10 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
+import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
-import org.springframework.expression.spel.ExpressionState;
 
 /**
  * PlaceHolder nodes are created for tokens that come through from the grammar purely to give us additional positional
@@ -35,7 +36,7 @@ public class Placeholder extends SpelNodeImpl {
 	}
 
 	@Override
-	public String getValueInternal(ExpressionState state) throws SpelException {
+	public TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		throw new SpelException(getCharPositionInLine(), SpelMessages.PLACEHOLDER_SHOULD_NEVER_BE_EVALUATED);
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Projection.java

@@ -22,8 +22,9 @@ import java.util.List;
 import java.util.Map;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -43,9 +44,12 @@ public class Projection extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object operand = state.getActiveContextObject();
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue op = state.getActiveContextObject();
 
+		Object operand = op.getValue();
+		TypeDescriptor operandTypeDescriptor = op.getTypeDescriptor();
+		
 		// When the input is a map, we push a special context object on the stack
 		// before calling the specified operation. This special context object
 		// has two fields 'key' and 'value' that refer to the map entries key
@@ -56,21 +60,21 @@ public class Projection extends SpelNodeImpl {
 			List<Object> result = new ArrayList<Object>();
 			for (Object k : mapdata.keySet()) {
 				try {
-					state.pushActiveContextObject(new KeyValuePair(k, mapdata.get(k)));
+					state.pushActiveContextObject(new TypedValue(new KeyValuePair(k, mapdata.get(k)),TypeDescriptor.valueOf(KeyValuePair.class)));
 					result.add(getChild(0).getValueInternal(state));
 				} finally {
 					state.popActiveContextObject();
 				}
 			}
-			return result;
-		} else if (operand instanceof Collection) {
+			return new TypedValue(result,TypeDescriptor.valueOf(Map.class)); // TODO unable to build correct type descriptor
+		} else if (operand instanceof List) {
 			List<Object> data = new ArrayList<Object>();
 			data.addAll((Collection<?>) operand);
 			List<Object> result = new ArrayList<Object>();
 			int idx = 0;
 			for (Object element : data) {
 				try {
-					state.pushActiveContextObject(element);
+					state.pushActiveContextObject(new TypedValue(element,TypeDescriptor.valueOf(op.getTypeDescriptor().getType())));
 					state.enterScope("index", idx);
 					result.add(getChild(0).getValueInternal(state));
 				} finally {
@@ -79,7 +83,7 @@ public class Projection extends SpelNodeImpl {
 				}
 				idx++;
 			}
-			return result;
+			return new TypedValue(result,op.getTypeDescriptor());
 		} else {
 			throw new SpelException(SpelMessages.PROJECTION_NOT_SUPPORTED_ON_TYPE, operand.getClass().getName());
 		}

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/PropertyOrFieldReference.java

@@ -23,6 +23,7 @@ import org.antlr.runtime.Token;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -49,7 +50,7 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws SpelException {
+	public TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		return readProperty(state, this.name);
 	}
 
@@ -75,14 +76,14 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 	 * @return the value of the property
 	 * @throws SpelException if any problem accessing the property or it cannot be found
 	 */
-	private Object readProperty(ExpressionState state, String name) throws SpelException {
-		Object contextObject = state.getActiveContextObject();
+	private TypedValue readProperty(ExpressionState state, String name) throws SpelException {
+		TypedValue contextObject = state.getActiveContextObject();
 		EvaluationContext eContext = state.getEvaluationContext();
 
 		PropertyAccessor accessorToUse = this.cachedReadAccessor;
 		if (accessorToUse != null) {
 			try {
-				return accessorToUse.read(state.getEvaluationContext(), contextObject, name);
+				return accessorToUse.read(state.getEvaluationContext(), contextObject.getValue(), name);
 			}
 			catch (AccessException ae) {
 				// this is OK - it may have gone stale due to a class change,
@@ -91,7 +92,7 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 			}
 		}
 
-		Class<?> contextObjectClass = getObjectClass(contextObject);
+		Class<?> contextObjectClass = getObjectClass(contextObject.getValue());
 		List<PropertyAccessor> accessorsToTry = getPropertyAccessorsToTry(contextObjectClass, state);
 
 		// Go through the accessors that may be able to resolve it. If they are a cacheable accessor then
@@ -100,9 +101,9 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 		if (accessorsToTry != null) {
 			try {
 				for (PropertyAccessor accessor : accessorsToTry) {
-					if (accessor.canRead(eContext, contextObject, name)) {
+					if (accessor.canRead(eContext, contextObject.getValue(), name)) {
 						this.cachedReadAccessor = accessor;
-						return accessor.read(eContext, contextObject, name);
+						return accessor.read(eContext, contextObject.getValue(), name);
 					}
 				}
 			}
@@ -115,13 +116,13 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 	}
 
 	private void writeProperty(ExpressionState state, String name, Object newValue) throws SpelException {
-		Object contextObject = state.getActiveContextObject();
+		TypedValue contextObject = state.getActiveContextObject();
 		EvaluationContext eContext = state.getEvaluationContext();
 
 		PropertyAccessor accessorToUse = this.cachedWriteAccessor;
 		if (accessorToUse != null) {
 			try {				
-				accessorToUse.write(state.getEvaluationContext(), contextObject, name, newValue);
+				accessorToUse.write(state.getEvaluationContext(), contextObject.getValue(), name, newValue);
 				return;
 			}
 			catch (AccessException ae) {
@@ -131,15 +132,15 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 			}
 		}
 
-		Class<?> contextObjectClass = getObjectClass(contextObject);
+		Class<?> contextObjectClass = getObjectClass(contextObject.getValue());
 
 		List<PropertyAccessor> accessorsToTry = getPropertyAccessorsToTry(contextObjectClass, state);
 		if (accessorsToTry != null) {
 			try {
 				for (PropertyAccessor accessor : accessorsToTry) {
-					if (accessor.canWrite(eContext, contextObject, name)) {
+					if (accessor.canWrite(eContext, contextObject.getValue(), name)) {
 						this.cachedWriteAccessor = accessor;
-						accessor.write(eContext, contextObject, name, newValue);
+						accessor.write(eContext, contextObject.getValue(), name, newValue);
 						return;
 					}
 				}
@@ -153,7 +154,7 @@ public class PropertyOrFieldReference extends SpelNodeImpl {
 	}
 
 	public boolean isWritableProperty(String name, ExpressionState state) throws SpelException {
-		Object contextObject = state.getActiveContextObject();
+		Object contextObject = state.getActiveContextObject().getValue();
 		EvaluationContext eContext = state.getEvaluationContext();
 		if (contextObject == null) {
 			throw new SpelException(SpelMessages.ATTEMPTED_PROPERTY_FIELD_REF_ON_NULL_CONTEXT_OBJECT, name);

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/QualifiedIdentifier.java

@@ -17,8 +17,8 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 
 /**
@@ -39,7 +39,7 @@ public class QualifiedIdentifier extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		// Cache the concatenation of child identifiers
 		if (this.value == null) {
 			StringBuilder sb = new StringBuilder();
@@ -47,11 +47,11 @@ public class QualifiedIdentifier extends SpelNodeImpl {
 				if (i > 0) {
 					sb.append(".");
 				}
-				sb.append(getChild(i).getValueInternal(state));
+				sb.append(getChild(i).getValueInternal(state).getValue());
 			}
 			this.value = sb.toString();
 		}
-		return this.value;
+		return new TypedValue(this.value,STRING_TYPE_DESCRIPTOR);
 	}
 
 	@Override

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/RealLiteral.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
 
 /**
  * @author Andy Clement
@@ -24,15 +25,15 @@ import org.antlr.runtime.Token;
  */
 public class RealLiteral extends Literal {
 
-	private final Double value;
+	private final TypedValue value;
 
 	public RealLiteral(Token payload) {
 		super(payload);
-		value = Double.parseDouble(payload.getText());
+		value = new TypedValue(Double.parseDouble(payload.getText()),DOUBLE_TYPE_DESCRIPTOR);
 	}
 
 	@Override
-	public Double getLiteralValue() {
+	public TypedValue getLiteralValue() {
 		return this.value;
 	}
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Selection.java

@@ -22,8 +22,9 @@ import java.util.List;
 import java.util.Map;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -51,15 +52,17 @@ public class Selection extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
-		Object operand = state.getActiveContextObject();
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
+		TypedValue op = state.getActiveContextObject();
+		Object operand = op.getValue();
+		
 		SpelNodeImpl selectionCriteria = getChild(0);
 		if (operand instanceof Map) {
 			Map<?, ?> mapdata = (Map<?, ?>) operand;
 			List<Object> result = new ArrayList<Object>();
 			for (Object k : mapdata.keySet()) {
 				try {
-					Object kvpair = new KeyValuePair(k, mapdata.get(k));
+					TypedValue kvpair = new TypedValue(new KeyValuePair(k, mapdata.get(k)),TypeDescriptor.valueOf(KeyValuePair.class));
 					state.pushActiveContextObject(kvpair);
 					Object o = selectionCriteria.getValueInternal(state);
 					if (o instanceof Boolean) {
@@ -79,10 +82,10 @@ public class Selection extends SpelNodeImpl {
 					return null;
 				}
 				if (variant == LAST) {
-					return result.get(result.size() - 1);
+					return new TypedValue(result.get(result.size() - 1),TypeDescriptor.valueOf(op.getTypeDescriptor().getElementType()));
 				}
 			}
-			return result;
+			return new TypedValue(result,op.getTypeDescriptor());
 		} else if (operand instanceof Collection) {
 			List<Object> data = new ArrayList<Object>();
 			data.addAll((Collection<?>) operand);
@@ -90,13 +93,13 @@ public class Selection extends SpelNodeImpl {
 			int idx = 0;
 			for (Object element : data) {
 				try {
-					state.pushActiveContextObject(element);
+					state.pushActiveContextObject(new TypedValue(element,TypeDescriptor.valueOf(op.getTypeDescriptor().getElementType())));
 					state.enterScope("index", idx);
-					Object o = selectionCriteria.getValueInternal(state);
+					Object o = selectionCriteria.getValueInternal(state).getValue();
 					if (o instanceof Boolean) {
 						if (((Boolean) o).booleanValue() == true) {
 							if (variant == FIRST)
-								return element;
+								return new TypedValue(element,TypeDescriptor.valueOf(op.getTypeDescriptor().getElementType()));
 							result.add(element);
 						}
 					} else {
@@ -113,9 +116,9 @@ public class Selection extends SpelNodeImpl {
 				return null;
 			}
 			if (variant == LAST) {
-				return result.get(result.size() - 1);
+				return new TypedValue(result.get(result.size() - 1),TypeDescriptor.valueOf(op.getTypeDescriptor().getElementType()));
 			}
-			return result;
+			return new TypedValue(result,op.getTypeDescriptor());
 		} else {
 			throw new SpelException(getCharPositionInLine(), SpelMessages.INVALID_TYPE_FOR_SELECTION,
 					(operand == null ? "null" : operand.getClass().getName()));

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/SpelNodeImpl.java

@@ -20,8 +20,8 @@ import java.io.Serializable;
 
 import org.antlr.runtime.Token;
 import org.antlr.runtime.tree.CommonTree;
-import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.common.ExpressionUtils;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
@@ -36,10 +36,7 @@ import org.springframework.expression.spel.support.StandardEvaluationContext;
  * @author Andy Clement
  * @since 3.0
  */
-public abstract class SpelNodeImpl extends CommonTree implements SpelNode, Serializable {
-
-	protected static TypeDescriptor BOOLEAN_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Boolean.class);
-	protected static TypeDescriptor INTEGER_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(Integer.class);
+public abstract class SpelNodeImpl extends CommonTree implements SpelNode, Serializable, CommonTypeDescriptors {
 	
 	/**
 	 * The Antlr parser uses this constructor to build SpelNodes.
@@ -51,7 +48,7 @@ public abstract class SpelNodeImpl extends CommonTree implements SpelNode, Seria
 
 	public final Object getValue(ExpressionState expressionState) throws EvaluationException {
 		if (expressionState != null) {
-			return getValueInternal(expressionState);
+			return getValueInternal(expressionState).getValue();
 		}
 		else {
 			return getValue(new ExpressionState(new StandardEvaluationContext()));
@@ -88,7 +85,7 @@ public abstract class SpelNodeImpl extends CommonTree implements SpelNode, Seria
 
 	@SuppressWarnings("unchecked")
 	protected final <T> T getValue(ExpressionState state, Class<T> desiredReturnType) throws EvaluationException {
-		Object result = getValueInternal(state);
+		Object result = getValueInternal(state).getValue();
 		if (result != null && desiredReturnType != null) {
 			Class<?> resultType = result.getClass();
 			if (desiredReturnType.isAssignableFrom(resultType)) {
@@ -105,7 +102,7 @@ public abstract class SpelNodeImpl extends CommonTree implements SpelNode, Seria
 	}
 
 
-	public abstract Object getValueInternal(ExpressionState expressionState) throws EvaluationException;
+	public abstract TypedValue getValueInternal(ExpressionState expressionState) throws EvaluationException;
 
 	public abstract String toStringAST();
 

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/StringLiteral.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
+import org.springframework.expression.TypedValue;
 
 /**
  * @author Andy Clement
@@ -25,24 +26,24 @@ import org.antlr.runtime.Token;
  */
 public class StringLiteral extends Literal {
 
-	private final String value;
+	private final TypedValue value;
 
 	public StringLiteral(Token payload) {
 		super(payload);
 		String val = payload.getText();
 		// TODO should these have been skipped being created by the parser rules? or not?
 		val = val.substring(1, val.length() - 1);
-		this.value = val.replaceAll("''", "'");
+		this.value = new TypedValue(val.replaceAll("''", "'"),STRING_TYPE_DESCRIPTOR);
 	}
 
 	@Override
-	public String getLiteralValue() {
+	public TypedValue getLiteralValue() {
 		return this.value;
 	}
 
 	@Override
 	public String toString() {
-		return "'" + getLiteralValue() + "'";
+		return "'" + getLiteralValue().getValue() + "'";
 	}
 
 }

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Ternary.java

@@ -17,8 +17,8 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 
@@ -42,7 +42,7 @@ public class Ternary extends SpelNodeImpl {
 	 * executing the chosen alternative
 	 */
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		Boolean value = getChild(0).getValue(state, Boolean.class);
 		try {
 			if (Boolean.TRUE.equals(value)) {

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/TypeReference.java

@@ -17,8 +17,8 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
 import org.springframework.expression.EvaluationException;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 
@@ -34,17 +34,17 @@ public class TypeReference extends SpelNodeImpl {
 	}
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws EvaluationException {
+	public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
 		// TODO possible optimization here if we cache the discovered type reference, but can we do that?
-		String typename = (String) getChild(0).getValueInternal(state);
+		String typename = (String) getChild(0).getValueInternal(state).getValue();
 		if (typename.indexOf(".") == -1 && Character.isLowerCase(typename.charAt(0))) {
 			TypeCode tc = TypeCode.forName(typename);
 			if (tc != TypeCode.OBJECT) {
 				// it is a primitive type
-				return tc.getType();
+				return new TypedValue(tc.getType(),CLASS_TYPE_DESCRIPTOR);
 			}
 		}
-		return state.findType(typename);
+		return new TypedValue(state.findType(typename),CLASS_TYPE_DESCRIPTOR);
 	}
 
 	@Override

org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/VariableReference.java

@@ -17,7 +17,7 @@
 package org.springframework.expression.spel.ast;
 
 import org.antlr.runtime.Token;
-
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.ExpressionState;
 import org.springframework.expression.spel.SpelException;
 import org.springframework.expression.spel.SpelMessages;
@@ -44,14 +44,14 @@ public class VariableReference extends SpelNodeImpl {
 
 
 	@Override
-	public Object getValueInternal(ExpressionState state) throws SpelException {
+	public TypedValue getValueInternal(ExpressionState state) throws SpelException {
 		if (this.name.equals(THIS)) {
 			return state.getActiveContextObject();
 		}
 		if (this.name.equals(ROOT)) {
 			return state.getRootContextObject();
 		}
-		Object result = state.lookupVariable(this.name);
+		TypedValue result = state.lookupVariable(this.name);
 		if (result == null) {
 			throw new SpelException(getCharPositionInLine(), SpelMessages.VARIABLE_NOT_FOUND, this.name);
 		}

org.springframework.expression/src/main/java/org/springframework/expression/spel/support/BooleanTypedValue.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2002-2009 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.expression.spel.support;
+
+import org.springframework.expression.TypedValue;
+import org.springframework.expression.spel.ast.SpelNodeImpl;
+
+/**
+ * @author Andy Clement
+ * @since 3.0
+ */
+public class BooleanTypedValue extends TypedValue {
+
+	public static final BooleanTypedValue True = new BooleanTypedValue(true);
+	public static final BooleanTypedValue False = new BooleanTypedValue(false);
+	
+	private BooleanTypedValue(boolean b) {
+		super(b,SpelNodeImpl.BOOLEAN_TYPE_DESCRIPTOR);
+	}
+	
+	public static BooleanTypedValue forValue(boolean b) {
+		if (b) {
+			return True;
+		} else {
+			return False;
+		}
+	}
+}

org.springframework.expression/src/main/java/org/springframework/expression/spel/support/ReflectiveConstructorExecutor.java

@@ -18,9 +18,11 @@ package org.springframework.expression.spel.support;
 
 import java.lang.reflect.Constructor;
 
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.ConstructorExecutor;
 import org.springframework.expression.EvaluationContext;
+import org.springframework.expression.TypedValue;
 
 /**
  * A simple ConstructorExecutor implementation that runs a constructor using reflective invocation.
@@ -42,7 +44,7 @@ class ReflectiveConstructorExecutor implements ConstructorExecutor {
 		this.argsRequiringConversion = argsRequiringConversion;
 	}
 
-	public Object execute(EvaluationContext context, Object... arguments) throws AccessException {
+	public TypedValue execute(EvaluationContext context, Object... arguments) throws AccessException {
 		try {
 			if (argsRequiringConversion != null && arguments != null) {
 				ReflectionHelper.convertArguments(c.getParameterTypes(), c.isVarArgs(),
@@ -54,7 +56,7 @@ class ReflectiveConstructorExecutor implements ConstructorExecutor {
 			if (!c.isAccessible()) {
 				c.setAccessible(true);
 			}
-			return c.newInstance(arguments);
+			return new TypedValue(c.newInstance(arguments),TypeDescriptor.valueOf(c.getClass()));
 		}
 		catch (Exception ex) {
 			throw new AccessException("Problem invoking constructor: " + c, ex);

org.springframework.expression/src/main/java/org/springframework/expression/spel/support/ReflectiveMethodExecutor.java

@@ -18,9 +18,12 @@ package org.springframework.expression.spel.support;
 
 import java.lang.reflect.Method;
 
+import org.springframework.core.MethodParameter;
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.MethodExecutor;
+import org.springframework.expression.TypedValue;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -42,7 +45,7 @@ class ReflectiveMethodExecutor implements MethodExecutor {
 	}
 
 
-	public Object execute(EvaluationContext context, Object target, Object... arguments) throws AccessException {
+	public TypedValue execute(EvaluationContext context, Object target, Object... arguments) throws AccessException {
 		try {
 			if (this.argsRequiringConversion != null && arguments != null) {
 				ReflectionHelper.convertArguments(this.method.getParameterTypes(), this.method.isVarArgs(),
@@ -52,7 +55,7 @@ class ReflectiveMethodExecutor implements MethodExecutor {
 				arguments = ReflectionHelper.setupArgumentsForVarargsInvocation(this.method.getParameterTypes(), arguments);
 			}
 			ReflectionUtils.makeAccessible(this.method);
-			return this.method.invoke(target, arguments);
+			return new TypedValue(this.method.invoke(target, arguments), new TypeDescriptor(new MethodParameter(method,-1)));
 		}
 		catch (Exception ex) {
 			throw new AccessException("Problem invoking method: " + this.method, ex);

org.springframework.expression/src/main/java/org/springframework/expression/spel/support/ReflectivePropertyResolver.java

@@ -30,6 +30,7 @@ import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.util.StringUtils;
 
@@ -85,7 +86,7 @@ public class ReflectivePropertyResolver implements PropertyAccessor {
 		return false;
 	}
 
-	public Object read(EvaluationContext context, Object target, String name) throws AccessException {
+	public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
 		if (target == null) {
 			return null;
 		}
@@ -95,7 +96,7 @@ public class ReflectivePropertyResolver implements PropertyAccessor {
 			if (target instanceof Class) {
 				throw new AccessException("Cannot access length on array class itself");
 			}
-			return Array.getLength(target);
+			return new TypedValue(Array.getLength(target),TypeDescriptor.valueOf(Integer.TYPE));
 		}
 
 		CacheKey cacheKey = new CacheKey(type, name);
@@ -113,7 +114,8 @@ public class ReflectivePropertyResolver implements PropertyAccessor {
 			if (method != null) {
 				try {
 					ReflectionUtils.makeAccessible(method);
-					return method.invoke(target);
+					TypeDescriptor resultTypeDescriptor = new TypeDescriptor(new MethodParameter(method,-1));
+					return new TypedValue(method.invoke(target),resultTypeDescriptor);
 				}
 				catch (Exception ex) {
 					throw new AccessException("Unable to access property '" + name + "' through getter", ex);
@@ -133,7 +135,7 @@ public class ReflectivePropertyResolver implements PropertyAccessor {
 			if (field != null) {
 				try {
 					ReflectionUtils.makeAccessible(field);
-					return field.get(target);
+					return new TypedValue(field.get(target),new TypeDescriptor(field));
 				}
 				catch (Exception ex) {
 					throw new AccessException("Unable to access field: " + name, ex);

org.springframework.expression/src/main/java/org/springframework/expression/spel/support/StandardEvaluationContext.java

@@ -22,6 +22,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.ConstructorResolver;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.MethodResolver;
@@ -30,6 +31,7 @@ import org.springframework.expression.PropertyAccessor;
 import org.springframework.expression.TypeComparator;
 import org.springframework.expression.TypeConverter;
 import org.springframework.expression.TypeLocator;
+import org.springframework.expression.TypedValue;
 import org.springframework.util.Assert;
 
 /**
@@ -43,7 +45,7 @@ import org.springframework.util.Assert;
  */
 public class StandardEvaluationContext implements EvaluationContext {
 
-	private Object rootObject;
+	private TypedValue rootObject;
 
 	private final Map<String, Object> variables = new HashMap<String, Object>();
 
@@ -68,10 +70,14 @@ public class StandardEvaluationContext implements EvaluationContext {
 	}
 
 	public void setRootObject(Object rootObject) {
-		this.rootObject = rootObject;
+		this.rootObject = new TypedValue(rootObject,TypeDescriptor.forObject(rootObject));
 	}
 
-	public Object getRootObject() {
+	public void setRootObject(Object rootObject, TypeDescriptor typeDescriptor) {
+		this.rootObject = new TypedValue(rootObject,typeDescriptor);
+	}
+
+	public TypedValue getRootObject() {
 		return this.rootObject;
 	}
 

org.springframework.expression/src/test/java/org/springframework/expression/spel/ExpressionLanguageScenarioTests.java

@@ -23,12 +23,14 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Expression;
 import org.springframework.expression.ParseException;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.antlr.SpelAntlrExpressionParser;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 
@@ -235,6 +237,7 @@ public class ExpressionLanguageScenarioTests extends ExpressionTestCase {
 	private static class FruitColourAccessor implements PropertyAccessor {
 
 		private static Map<String,Color> propertyMap = new HashMap<String,Color>();
+		private static TypeDescriptor mapElementTypeDescriptor = TypeDescriptor.valueOf(Color.class);
 
 		static {
 			propertyMap.put("banana",Color.yellow);
@@ -253,8 +256,8 @@ public class ExpressionLanguageScenarioTests extends ExpressionTestCase {
 			return propertyMap.containsKey(name);
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-			return propertyMap.get(name);
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+			return new TypedValue(propertyMap.get(name),mapElementTypeDescriptor);
 		}
 
 		public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {
@@ -292,8 +295,8 @@ public class ExpressionLanguageScenarioTests extends ExpressionTestCase {
 			return propertyMap.containsKey(name);
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-			return propertyMap.get(name);
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+			return new TypedValue(propertyMap.get(name),TypeDescriptor.valueOf(Color.class));
 		}
 
 		public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {

org.springframework.expression/src/test/java/org/springframework/expression/spel/MapAccessTests.java

@@ -22,7 +22,9 @@ import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.Expression;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.antlr.SpelAntlrExpressionParser;
+import org.springframework.expression.spel.ast.CommonTypeDescriptors;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 
 /**
@@ -67,8 +69,8 @@ public class MapAccessTests extends ExpressionTestCase {
 			return (((Map) target).containsKey(name));
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-			return ((Map) target).get(name);
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+			return new TypedValue(((Map) target).get(name),CommonTypeDescriptors.OBJECT_TYPE_DESCRIPTOR);
 		}
 
 		public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {

org.springframework.expression/src/test/java/org/springframework/expression/spel/OperatorTests.java

@@ -16,6 +16,8 @@
 
 package org.springframework.expression.spel;
 
+import org.springframework.expression.spel.ast.Operator;
+
 /**
  * Tests the evaluation of expressions using relational operators.
  * 
@@ -48,6 +50,12 @@ public class OperatorTests extends ExpressionTestCase {
 		evaluate("6 == 6", true, Boolean.class);
 	}
 
+	public void testNotEqual() {
+		evaluate("3 != 5", true, Boolean.class);
+		evaluate("5 != 3", true, Boolean.class);
+		evaluate("6 != 6", false, Boolean.class);
+	}
+
 	public void testGreaterThanOrEqual() {
 		evaluate("3 >= 5", false, Boolean.class);
 		evaluate("5 >= 3", true, Boolean.class);
@@ -79,6 +87,10 @@ public class OperatorTests extends ExpressionTestCase {
 		evaluate("3 % 2", 1, Integer.class);
 	}
 
+	public void testDivide() {
+		evaluate("4L/2L",2L,Long.class);
+	}
+	
 	public void testMathOperatorDivide_ConvertToDouble() {
 		evaluateAndAskForReturnType("8/4", new Double(2.0), Double.class);
 	}
@@ -92,6 +104,10 @@ public class OperatorTests extends ExpressionTestCase {
 	// }
 
 	public void testDoubles() {
+		evaluate("3.0d == 5.0d", false, Boolean.class);
+		evaluate("3.0d == 3.0d", true, Boolean.class);
+		evaluate("3.0d != 5.0d", true, Boolean.class);
+		evaluate("3.0d != 3.0d", false, Boolean.class);
 		evaluate("3.0d + 5.0d", 8.0d, Double.class);
 		evaluate("3.0d - 5.0d", -2.0d, Double.class);
 		evaluate("3.0d * 5.0d", 15.0d, Double.class);
@@ -100,6 +116,10 @@ public class OperatorTests extends ExpressionTestCase {
 	}
 
 	public void testFloats() {
+		evaluate("3.0f == 5.0f", false, Boolean.class);
+		evaluate("3.0f == 3.0f", true, Boolean.class);
+		evaluate("3.0f != 5.0f", true, Boolean.class);
+		evaluate("3.0f != 3.0f", false, Boolean.class);
 		evaluate("3.0f + 5.0f", 8.0d, Double.class);
 		evaluate("3.0f - 5.0f", -2.0d, Double.class);
 		evaluate("3.0f * 5.0f", 15.0d, Double.class);
@@ -107,6 +127,17 @@ public class OperatorTests extends ExpressionTestCase {
 		evaluate("5.0f % 3.1f", 1.9d, Double.class);
 	}
 	
+	public void testOperatorStrings() throws Exception {
+		Operator node = getOperatorNode((SpelExpression)parser.parseExpression("1==3"));
+		assertEquals("==",node.getOperatorName());
+
+		node = getOperatorNode((SpelExpression)parser.parseExpression("1!=3"));
+		assertEquals("!=",node.getOperatorName());
+		
+		node = getOperatorNode((SpelExpression)parser.parseExpression("3/3"));
+		assertEquals("/",node.getOperatorName());
+	}
+	
 	public void testMixedOperands_FloatsAndDoubles() {
 		evaluate("3.0d + 5.0f", 8.0d, Double.class);
 		evaluate("3.0D - 5.0f", -2.0d, Double.class);
@@ -125,4 +156,37 @@ public class OperatorTests extends ExpressionTestCase {
 		evaluate("5.5D % 3", 2.5, Double.class);		
 	}
 	
+	public void testStrings() {
+		evaluate("'abc' == 'abc'",true,Boolean.class);
+		evaluate("'abc' == 'def'",false,Boolean.class);
+		evaluate("'abc' != 'abc'",false,Boolean.class);
+		evaluate("'abc' != 'def'",true,Boolean.class);
+	}
+	
+	public void testLongs() {
+		evaluate("3L == 4L", false, Boolean.class);
+		evaluate("3L == 3L", true, Boolean.class);
+		evaluate("3L != 4L", true, Boolean.class);
+		evaluate("3L != 3L", false, Boolean.class);
+	}
+	
+	private Operator getOperatorNode(SpelExpression e) {
+		SpelNode node = e.getAST();
+		return (Operator)findNode(node,Operator.class);
+	}
+	
+	private SpelNode findNode(SpelNode node, Class<Operator> clazz) {
+		if (clazz.isAssignableFrom(node.getClass())) {
+			return node;
+		}
+		int childCount = node.getChildCount();
+		for (int i=0;i<childCount;i++) {
+			SpelNode possible = findNode(node.getChild(i),clazz);
+			if (possible!=null) {
+				return possible;
+			}
+		}
+		return null;
+	}
+	
 }

org.springframework.expression/src/test/java/org/springframework/expression/spel/PerformanceTests.java

@@ -21,8 +21,6 @@ import junit.framework.TestCase;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.Expression;
 import org.springframework.expression.spel.antlr.SpelAntlrExpressionParser;
-import org.springframework.expression.spel.ast.ConstructorReference;
-import org.springframework.expression.spel.ast.PropertyOrFieldReference;
 
 /**
  * Tests the evaluation of real expressions in a real context.
@@ -31,7 +29,7 @@ import org.springframework.expression.spel.ast.PropertyOrFieldReference;
  */
 public class PerformanceTests extends TestCase {
 
-	public static final int ITERATIONS = 100000;
+	public static final int ITERATIONS = 10000;
 	public static final boolean report = true;
 
 	private static SpelAntlrExpressionParser parser = new SpelAntlrExpressionParser();
@@ -41,6 +39,15 @@ public class PerformanceTests extends TestCase {
 		long starttime = 0;
 		long endtime = 0;
 
+		// warmup
+		for (int i = 0; i < ITERATIONS; i++) {
+			Expression expr = parser.parseExpression("placeOfBirth.city");
+			if (expr == null) {
+				fail("Parser returned null for expression");
+			}
+			Object value = expr.getValue(eContext);
+		}
+		
 		starttime = System.currentTimeMillis();
 		for (int i = 0; i < ITERATIONS; i++) {
 			Expression expr = parser.parseExpression("placeOfBirth.city");
@@ -74,6 +81,15 @@ public class PerformanceTests extends TestCase {
 	public void testPerformanceOfMethodAccess() throws Exception {
 		long starttime = 0;
 		long endtime = 0;
+		
+		// warmup
+		for (int i = 0; i < ITERATIONS; i++) {
+			Expression expr = parser.parseExpression("getPlaceOfBirth().getCity()");
+			if (expr == null) {
+				fail("Parser returned null for expression");
+			}
+			Object value = expr.getValue(eContext);
+		}
 
 		starttime = System.currentTimeMillis();
 		for (int i = 0; i < ITERATIONS; i++) {

org.springframework.expression/src/test/java/org/springframework/expression/spel/PropertyAccessTests.java

@@ -21,7 +21,9 @@ import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Expression;
 import org.springframework.expression.PropertyAccessor;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.antlr.SpelAntlrExpressionParser;
+import org.springframework.expression.spel.ast.CommonTypeDescriptors;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
 
 /**
@@ -57,7 +59,7 @@ public class PropertyAccessTests extends ExpressionTestCase {
 		// any 'default' ones
 		ctx.addPropertyAccessor(new StringyPropertyAccessor());
 		Expression expr = parser.parseExpression("new String('hello').flibbles");
-		Integer i = (Integer) expr.getValue(ctx, Integer.class);
+		Integer i = expr.getValue(ctx, Integer.class);
 		assertEquals((int) i, 7);
 
 		// The reflection one will be used for other properties...
@@ -67,7 +69,7 @@ public class PropertyAccessTests extends ExpressionTestCase {
 
 		expr = parser.parseExpression("new String('hello').flibbles");
 		expr.setValue(ctx, 99);
-		i = (Integer) expr.getValue(ctx, Integer.class);
+		i = expr.getValue(ctx, Integer.class);
 		assertEquals((int) i, 99);
 
 		// Cannot set it to a string value
@@ -103,10 +105,10 @@ public class PropertyAccessTests extends ExpressionTestCase {
 			return (name.equals("flibbles"));
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
 			if (!name.equals("flibbles"))
 				throw new RuntimeException("Assertion Failed! name should be flibbles");
-			return flibbles;
+			return new TypedValue(flibbles,CommonTypeDescriptors.STRING_TYPE_DESCRIPTOR);
 		}
 
 		public void write(EvaluationContext context, Object target, String name, Object newValue)

org.springframework.expression/src/test/java/org/springframework/expression/spel/ScenariosForSpringSecurity.java

@@ -18,6 +18,7 @@ package org.springframework.expression.spel;
 
 import java.lang.reflect.Method;
 
+import org.springframework.core.MethodParameter;
 import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.expression.AccessException;
 import org.springframework.expression.EvaluationContext;
@@ -27,6 +28,7 @@ import org.springframework.expression.MethodExecutor;
 import org.springframework.expression.MethodResolver;
 import org.springframework.expression.PropertyAccessor;
 import org.springframework.expression.TypeConverter;
+import org.springframework.expression.TypedValue;
 import org.springframework.expression.spel.antlr.SpelAntlrExpressionParser;
 import org.springframework.expression.spel.support.ReflectionHelper;
 import org.springframework.expression.spel.support.StandardEvaluationContext;
@@ -84,11 +86,11 @@ public class ScenariosForSpringSecurity extends ExpressionTestCase {
 		ctx.setRootObject(null);
 		
 		pAccessor.setPerson(new Person("Andy"));
-		value = (Boolean)expr.getValue(ctx,Boolean.class);
+		value = expr.getValue(ctx,Boolean.class);
 		assertTrue(value);
 		
 		pAccessor.setPerson(new Person("Christian"));
-		value = (Boolean)expr.getValue(ctx,Boolean.class);
+		value = expr.getValue(ctx,Boolean.class);
 		assertFalse(value);
 	}
 
@@ -210,8 +212,8 @@ public class ScenariosForSpringSecurity extends ExpressionTestCase {
 			return name.equals("principal");
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-			return new Principal();
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+			return new TypedValue(new Principal(),TypeDescriptor.valueOf(Principal.class));
 		}
 
 		public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {
@@ -240,8 +242,8 @@ public class ScenariosForSpringSecurity extends ExpressionTestCase {
 			return name.equals("p");
 		}
 
-		public Object read(EvaluationContext context, Object target, String name) throws AccessException {
-			return activePerson;
+		public TypedValue read(EvaluationContext context, Object target, String name) throws AccessException {
+			return new TypedValue(activePerson,TypeDescriptor.valueOf(Person.class));
 		}
 
 		public boolean canWrite(EvaluationContext context, Object target, String name) throws AccessException {
@@ -269,7 +271,7 @@ public class ScenariosForSpringSecurity extends ExpressionTestCase {
 				this.tc = typeConverter;
 			}
 
-			public Object execute(EvaluationContext context, Object target, Object... arguments)
+			public TypedValue execute(EvaluationContext context, Object target, Object... arguments)
 					throws AccessException {
 				try {
 					Method m = HasRoleExecutor.class.getMethod("hasRole", String[].class);
@@ -280,7 +282,7 @@ public class ScenariosForSpringSecurity extends ExpressionTestCase {
 					if (m.isVarArgs()) {
 						args = ReflectionHelper.setupArgumentsForVarargsInvocation(m.getParameterTypes(), args);
 					}
-					return m.invoke(null, args);
+					return new TypedValue(m.invoke(null, args), new TypeDescriptor(new MethodParameter(m,-1)));
 				}
 				catch (Exception ex) {
 					throw new AccessException("Problem invoking hasRole", ex);

org.springframework.expression/src/test/java/org/springframework/expression/spel/SetValueTests.java

@@ -17,6 +17,8 @@
 package org.springframework.expression.spel;
 
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Set;
 
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.Expression;
@@ -77,10 +79,15 @@ public class SetValueTests extends ExpressionTestCase {
 		setValue("placesLivedList[0]", new PlaceOfBirth("Wien"));
 	}
 	
-	public void testSetGenericListElementValueTypeCoersion() {
-		setValue("placesLivedList[0]", "Wien");
+	public void testSetGenericListElementValueTypeCoersionFail() {
+		// no type converter registered for String > PlaceOfBirth
+		setValueExpectError("placesLivedList[0]", "Wien");
 	}
 
+	public void testSetGenericListElementValueTypeCoersionOK() {
+		setValue("booleanList[0]", "true", Boolean.TRUE);
+	}
+	
 	public void testSetListElementNestedValue() {
 		setValue("placesLived[0].city", "Wien");
 	}
@@ -106,6 +113,46 @@ public class SetValueTests extends ExpressionTestCase {
 		setValue("SomeProperty", "true", Boolean.TRUE);
 	}
 	
+	public void testAssign() throws Exception {	
+		StandardEvaluationContext eContext = TestScenarioCreator.getTestEvaluationContext();
+		Expression e = parse("publicName='Andy'");
+		assertFalse(e.isWritable(eContext));
+		assertEquals("Andy",e.getValue(eContext));
+	}
+
+	/*
+	 * Testing the coercion of both the keys and the values to the correct type
+	 */
+	public void testSetGenericMapElementRequiresCoercion() throws Exception {
+		StandardEvaluationContext eContext = TestScenarioCreator.getTestEvaluationContext();
+		Expression e = parse("mapOfStringToBoolean[42]");
+		assertNull(e.getValue(eContext));
+		
+		// Key should be coerced to string representation of 42
+		e.setValue(eContext, "true");
+		
+		// All keys should be strings
+		Set ks = parse("mapOfStringToBoolean.keySet()").getValue(eContext,Set.class);
+		for (Object o: ks) {
+			assertEquals(String.class,o.getClass());
+		}
+		
+		// All values should be booleans
+		Collection vs = parse("mapOfStringToBoolean.values()").getValue(eContext,Collection.class);
+		for (Object o: vs) {
+			assertEquals(Boolean.class,o.getClass());
+		}
+		
+		// One final test check coercion on the key for a map lookup
+		Object o = e.getValue(eContext);
+		assertEquals(Boolean.TRUE,o);
+	}
+	
+
+	private Expression parse(String expressionString) throws Exception {
+		return parser.parseExpression(expressionString);
+	}
+	
 	/**
 	 * Call setValue() but expect it to fail.
 	 */
@@ -167,7 +214,12 @@ public class SetValueTests extends ExpressionTestCase {
 			StandardEvaluationContext lContext = TestScenarioCreator.getTestEvaluationContext();
 			assertTrue("Expression is not writeable but should be", e.isWritable(lContext));
 			e.setValue(lContext, value);
-			assertEquals("Retrieved value was not equal to set value", expectedValue, e.getValue(lContext));
+			Object a = expectedValue;
+			Object b = e.getValue(lContext);
+			if (!a.equals(b)) {
+				fail("Not the same: ["+a+"] type="+a.getClass()+"  ["+b+"] type="+b.getClass());
+//				assertEquals("Retrieved value was not equal to set value", expectedValue, e.getValue(lContext));
+			}
 		} catch (EvaluationException ee) {
 			ee.printStackTrace();
 			fail("Unexpected Exception: " + ee.getMessage());

org.springframework.expression/src/test/java/org/springframework/expression/spel/testresources/Inventor.java

@@ -9,6 +9,7 @@ import java.util.Map;
 @SuppressWarnings("unused")
 public class Inventor {
 	private String name;
+	public String publicName;
 	private PlaceOfBirth placeOfBirth;
 	Date birthdate;
 	private int sinNumber;
@@ -23,6 +24,8 @@ public class Inventor {
 	public boolean publicBoolean;
 	private boolean accessedThroughGetSet;
 	public List<Integer> listOfInteger = new ArrayList<Integer>();
+	public List<Boolean> booleanList = new ArrayList<Boolean>();
+	public Map<String,Boolean> mapOfStringToBoolean = new HashMap<String,Boolean>();
 	
 	public Inventor(String name, Date birthdate, String nationality) {
 		this.name = name;
@@ -37,6 +40,8 @@ public class Inventor {
 		testMap.put("friday", "freitag");
 		testMap.put("saturday", "samstag");
 		testMap.put("sunday", "sonntag");
+		booleanList.add(false);
+		booleanList.add(false);
 	}
 
 	public void setPlaceOfBirth(PlaceOfBirth placeOfBirth2) {

org.springframework.expression/src/test/java/org/springframework/expression/spel/testresources/PlaceOfBirth.java

@@ -21,4 +21,16 @@ public class PlaceOfBirth {
 		return i*2;
 	}
 	
+	public boolean equals(Object o) {
+		if (!(o instanceof PlaceOfBirth)) {
+			return false;
+		}
+		PlaceOfBirth oPOB = (PlaceOfBirth)o;
+		return (city.equals(oPOB.city));
+	}
+	
+	public int hashCode() {
+		return city.hashCode();
+	}
+	
 }