Extracted simple MethodInvokingBean as alternative to (and base class for) MethodInvokingFactoryBean

Issue: SPR-11196

spring-beans/src/main/java/org/springframework/beans/factory/config/MethodInvokingBean.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2002-2014 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.beans.factory.config;
+
+import java.lang.reflect.InvocationTargetException;
+
+import org.springframework.beans.TypeConverter;
+import org.springframework.beans.factory.BeanClassLoaderAware;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.support.ArgumentConvertingMethodInvoker;
+import org.springframework.util.ClassUtils;
+
+/**
+ * Simple method invoker bean: just invoking a target method, not expecting a result
+ * to expose to the container (in contrast to {@link MethodInvokingFactoryBean}).
+ *
+ * <p>This invoker supports any kind of target method. A static method may be specified
+ * by setting the {@link #setTargetMethod targetMethod} property to a String representing
+ * the static method name, with {@link #setTargetClass targetClass} specifying the Class
+ * that the static method is defined on. Alternatively, a target instance method may be
+ * specified, by setting the {@link #setTargetObject targetObject} property as the target
+ * object, and the {@link #setTargetMethod targetMethod} property as the name of the
+ * method to call on that target object. Arguments for the method invocation may be
+ * specified by setting the {@link #setArguments arguments} property.
+ *
+ * <p>This class depends on {@link #afterPropertiesSet()} being called once
+ * all properties have been set, as per the InitializingBean contract.
+ *
+ * <p>An example (in an XML based bean factory definition) of a bean definition
+ * which uses this class to call a static initialization method:
+ *
+ * <pre class="code">
+ * &lt;bean id="myObject" class="org.springframework.beans.factory.config.MethodInvokingBean">
+ *   &lt;property name="staticMethod" value="com.whatever.MyClass.init"/>
+ * &lt;/bean></pre>
+ *
+ * <p>An example of calling an instance method to start some server bean:
+ *
+ * <pre class="code">
+ * &lt;bean id="myStarter" class="org.springframework.beans.factory.config.MethodInvokingBean">
+ *   &lt;property name="targetObject" ref="myServer"/>
+ *   &lt;property name="targetMethod" value="start"/>
+ * &lt;/bean></pre>
+ *
+ * @author Juergen Hoeller
+ * @since 4.0.3
+ * @see MethodInvokingFactoryBean
+ * @see org.springframework.util.MethodInvoker
+ */
+public class MethodInvokingBean extends ArgumentConvertingMethodInvoker
+		implements BeanClassLoaderAware, BeanFactoryAware, InitializingBean {
+
+	private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader();
+
+	private ConfigurableBeanFactory beanFactory;
+
+
+	@Override
+	public void setBeanClassLoader(ClassLoader classLoader) {
+		this.beanClassLoader = classLoader;
+	}
+
+	@Override
+	protected Class<?> resolveClassName(String className) throws ClassNotFoundException {
+		return ClassUtils.forName(className, this.beanClassLoader);
+	}
+
+	@Override
+	public void setBeanFactory(BeanFactory beanFactory) {
+		if (beanFactory instanceof ConfigurableBeanFactory) {
+			this.beanFactory = (ConfigurableBeanFactory) beanFactory;
+		}
+	}
+
+	/**
+	 * Obtain the TypeConverter from the BeanFactory that this bean runs in,
+	 * if possible.
+	 * @see ConfigurableBeanFactory#getTypeConverter()
+	 */
+	@Override
+	protected TypeConverter getDefaultTypeConverter() {
+		if (this.beanFactory != null) {
+			return this.beanFactory.getTypeConverter();
+		}
+		else {
+			return super.getDefaultTypeConverter();
+		}
+	}
+
+
+	@Override
+	public void afterPropertiesSet() throws Exception {
+		prepare();
+		invokeWithTargetException();
+	}
+
+	/**
+	 * Perform the invocation and convert InvocationTargetException
+	 * into the underlying target exception.
+	 */
+	protected Object invokeWithTargetException() throws Exception {
+		try {
+			return invoke();
+		}
+		catch (InvocationTargetException ex) {
+			if (ex.getTargetException() instanceof Exception) {
+				throw (Exception) ex.getTargetException();
+			}
+			if (ex.getTargetException() instanceof Error) {
+				throw (Error) ex.getTargetException();
+			}
+			throw ex;
+		}
+	}
+
+}

spring-beans/src/main/java/org/springframework/beans/factory/config/MethodInvokingFactoryBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -16,17 +16,8 @@
 
 package org.springframework.beans.factory.config;
 
-import java.lang.reflect.InvocationTargetException;
-
-import org.springframework.beans.TypeConverter;
-import org.springframework.beans.factory.BeanClassLoaderAware;
-import org.springframework.beans.factory.BeanFactory;
-import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.factory.FactoryBeanNotInitializedException;
-import org.springframework.beans.factory.InitializingBean;
-import org.springframework.beans.support.ArgumentConvertingMethodInvoker;
-import org.springframework.util.ClassUtils;
 
 /**
  * {@link FactoryBean} which returns a value which is the result of a static or instance
@@ -44,10 +35,14 @@ import org.springframework.util.ClassUtils;
  * {@link #setSingleton singleton} property may be set to "false", to cause this
  * factory to invoke the target method each time it is asked for an object.
  *
- * <p>A static target method may be specified by setting the
+ * <p><b>NOTE: If your target method does not produce a result to expose, consider
- * {@link #setTargetMethod targetMethod} property to a String representing the static
+ * {@link MethodInvokingBean} instead, which avoids the type determination and
- * method name, with {@link #setTargetClass targetClass} specifying the Class that
+ * lifecycle limitations that this {@link MethodInvokingFactoryBean} comes with.</b>
- * the static method is defined on. Alternatively, a target instance method may be
+ *
+ * <p>This invoker supports any kind of target method. A static method may be specified
+ * by setting the {@link #setTargetMethod targetMethod} property to a String representing
+ * the static method name, with {@link #setTargetClass targetClass} specifying the Class
+ * that the static method is defined on. Alternatively, a target instance method may be
  * specified, by setting the {@link #setTargetObject targetObject} property as the target
  * object, and the {@link #setTargetMethod targetMethod} property as the name of the
  * method to call on that target object. Arguments for the method invocation may be
@@ -61,7 +56,7 @@ import org.springframework.util.ClassUtils;
  *
  * <pre class="code">
  * &lt;bean id="myObject" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
- *   &lt;property name="staticMethod">&lt;value>com.whatever.MyClassFactory.getInstance&lt;/value>&lt;/property>
+ *   &lt;property name="staticMethod" value="com.whatever.MyClassFactory.getInstance"/>
  * &lt;/bean></pre>
  *
  * <p>An example of calling a static method then an instance method to get at a
@@ -69,33 +64,26 @@ import org.springframework.util.ClassUtils;
  *
  * <pre class="code">
  * &lt;bean id="sysProps" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
- *   &lt;property name="targetClass">&lt;value>java.lang.System&lt;/value>&lt;/property>
+ *   &lt;property name="targetClass" value="java.lang.System"/>
- *   &lt;property name="targetMethod">&lt;value>getProperties&lt;/value>&lt;/property>
+ *   &lt;property name="targetMethod" value="getProperties"/>
  * &lt;/bean>
  *
  * &lt;bean id="javaVersion" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
- *   &lt;property name="targetObject">&lt;ref local="sysProps"/>&lt;/property>
+ *   &lt;property name="targetObject" value="sysProps"/>
- *   &lt;property name="targetMethod">&lt;value>getProperty&lt;/value>&lt;/property>
+ *   &lt;property name="targetMethod" value="getProperty"/>
- *   &lt;property name="arguments">
+ *   &lt;property name="arguments" value="java.version"/>
- *     &lt;list>
- *       &lt;value>java.version&lt;/value>
- *     &lt;/list>
- *   &lt;/property>
  * &lt;/bean></pre>
  *
  * @author Colin Sampaleanu
  * @author Juergen Hoeller
  * @since 21.11.2003
+ * @see MethodInvokingBean
+ * @see org.springframework.util.MethodInvoker
  */
-public class MethodInvokingFactoryBean extends ArgumentConvertingMethodInvoker
+public class MethodInvokingFactoryBean extends MethodInvokingBean implements FactoryBean<Object> {
-		implements FactoryBean<Object>, BeanClassLoaderAware, BeanFactoryAware, InitializingBean {
 
 	private boolean singleton = true;
 
-	private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader();
-
-	private ConfigurableBeanFactory beanFactory;
-
 	private boolean initialized = false;
 
 	/** Method call result in the singleton case */
@@ -104,75 +92,18 @@ public class MethodInvokingFactoryBean extends ArgumentConvertingMethodInvoker
 
 	/**
 	 * Set if a singleton should be created, or a new object on each
-	 * request else. Default is "true".
+	 * {@link #getObject()} request otherwise. Default is "true".
 	 */
 	public void setSingleton(boolean singleton) {
 		this.singleton = singleton;
 	}
 
-	@Override
-	public boolean isSingleton() {
-		return this.singleton;
-	}
-
-	@Override
-	public void setBeanClassLoader(ClassLoader classLoader) {
-		this.beanClassLoader = classLoader;
-	}
-
-	@Override
-	protected Class<?> resolveClassName(String className) throws ClassNotFoundException {
-		return ClassUtils.forName(className, this.beanClassLoader);
-	}
-
-	@Override
-	public void setBeanFactory(BeanFactory beanFactory) {
-		if (beanFactory instanceof ConfigurableBeanFactory) {
-			this.beanFactory = (ConfigurableBeanFactory) beanFactory;
-		}
-	}
-
-	/**
-	 * Obtain the TypeConverter from the BeanFactory that this bean runs in,
-	 * if possible.
-	 * @see ConfigurableBeanFactory#getTypeConverter()
-	 */
-	@Override
-	protected TypeConverter getDefaultTypeConverter() {
-		if (this.beanFactory != null) {
-			return this.beanFactory.getTypeConverter();
-		}
-		else {
-			return super.getDefaultTypeConverter();
-		}
-	}
-
-
 	@Override
 	public void afterPropertiesSet() throws Exception {
 		prepare();
 		if (this.singleton) {
 			this.initialized = true;
-			this.singletonObject = doInvoke();
+			this.singletonObject = invokeWithTargetException();
-		}
-	}
-
-	/**
-	 * Perform the invocation and convert InvocationTargetException
-	 * into the underlying target exception.
-	 */
-	private Object doInvoke() throws Exception {
-		try {
-			return invoke();
-		}
-		catch (InvocationTargetException ex) {
-			if (ex.getTargetException() instanceof Exception) {
-				throw (Exception) ex.getTargetException();
-			}
-			if (ex.getTargetException() instanceof Error) {
-				throw (Error) ex.getTargetException();
-			}
-			throw ex;
 		}
 	}
 
@@ -193,7 +124,7 @@ public class MethodInvokingFactoryBean extends ArgumentConvertingMethodInvoker
 		}
 		else {
 			// Prototype: new object on each call.
-			return doInvoke();
+			return invokeWithTargetException();
 		}
 	}
 
@@ -210,4 +141,9 @@ public class MethodInvokingFactoryBean extends ArgumentConvertingMethodInvoker
 		return getPreparedMethod().getReturnType();
 	}
 
+	@Override
+	public boolean isSingleton() {
+		return this.singleton;
+	}
+
 }

spring-beans/src/test/java/org/springframework/beans/factory/config/MethodInvokingFactoryBeanTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -16,26 +16,27 @@
 
 package org.springframework.beans.factory.config;
 
-import static org.junit.Assert.*;
-
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 
 import org.junit.Test;
+
 import org.springframework.beans.propertyeditors.StringTrimmerEditor;
 import org.springframework.beans.support.ArgumentConvertingMethodInvoker;
 import org.springframework.util.MethodInvoker;
 
+import static org.junit.Assert.*;
+
 /**
- * Unit tests for {@link MethodInvokingFactoryBean}.
+ * Unit tests for {@link MethodInvokingFactoryBean} and {@link MethodInvokingBean}.
  *
  * @author Colin Sampaleanu
  * @author Juergen Hoeller
  * @author Chris Beams
  * @since 21.11.2003
  */
-public final class MethodInvokingFactoryBeanTests {
+public class MethodInvokingFactoryBeanTests {
 
 	@Test
 	public void testParameterValidation() throws Exception {
@@ -246,7 +247,7 @@ public final class MethodInvokingFactoryBeanTests {
 		mcfb = new MethodInvokingFactoryBean();
 		mcfb.setTargetClass(TestClass1.class);
 		mcfb.setTargetMethod("supertypes");
-		mcfb.setArguments(new Object[] {new Integer(1), new Object()});
+		mcfb.setArguments(new Object[] {1, new Object()});
 		try {
 			mcfb.afterPropertiesSet();
 			mcfb.getObject();
@@ -291,7 +292,7 @@ public final class MethodInvokingFactoryBeanTests {
 		ArgumentConvertingMethodInvoker methodInvoker = new ArgumentConvertingMethodInvoker();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArgument");
-		methodInvoker.setArguments(new Object[] {new Integer(5)});
+		methodInvoker.setArguments(new Object[] {5});
 		methodInvoker.prepare();
 		methodInvoker.invoke();
 
@@ -305,49 +306,44 @@ public final class MethodInvokingFactoryBeanTests {
 
 	@Test
 	public void testInvokeWithIntArguments() throws Exception {
-		ArgumentConvertingMethodInvoker methodInvoker = new ArgumentConvertingMethodInvoker();
+		MethodInvokingBean methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new Object[] {new Integer[] {new Integer(5), new Integer(10)}});
+		methodInvoker.setArguments(new Object[]{new Integer[] {5, 10}});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 
-		methodInvoker = new ArgumentConvertingMethodInvoker();
+		methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new Object[] {new String[] {"5", "10"}});
+		methodInvoker.setArguments(new Object[]{new String[]{"5", "10"}});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 
-		methodInvoker = new ArgumentConvertingMethodInvoker();
+		methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new Integer[] {new Integer(5), new Integer(10)});
+		methodInvoker.setArguments(new Object[]{new Integer[] {5, 10}});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 
-		methodInvoker = new ArgumentConvertingMethodInvoker();
+		methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new String[] {"5", "10"});
+		methodInvoker.setArguments(new String[]{"5", "10"});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 
-		methodInvoker = new ArgumentConvertingMethodInvoker();
+		methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new Object[] {new Integer(5), new Integer(10)});
+		methodInvoker.setArguments(new Object[]{new Integer[] {5, 10}});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 
-		methodInvoker = new ArgumentConvertingMethodInvoker();
+		methodInvoker = new MethodInvokingBean();
 		methodInvoker.setTargetClass(TestClass1.class);
 		methodInvoker.setTargetMethod("intArguments");
-		methodInvoker.setArguments(new Object[] {"5", "10"});
+		methodInvoker.setArguments(new Object[]{"5", "10"});
-		methodInvoker.prepare();
+		methodInvoker.afterPropertiesSet();
-		methodInvoker.invoke();
 	}
 
+
 	public static class TestClass1 {
 
 		public static int _staticField1;
@@ -395,5 +391,4 @@ public final class MethodInvokingFactoryBeanTests {
 		}
 	}
 
-
 }