Polishing

spring-beans/src/main/java/org/springframework/beans/factory/xml/ParserContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -44,7 +44,7 @@ public final class ParserContext {
 
 	private BeanDefinition containingBeanDefinition;
 
-	private final Stack<ComponentDefinition> containingComponents = new Stack<ComponentDefinition>();
+	private final Stack<CompositeComponentDefinition> containingComponents = new Stack<CompositeComponentDefinition>();
 
 
 	public ParserContext(XmlReaderContext readerContext, BeanDefinitionParserDelegate delegate) {
@@ -90,8 +90,7 @@ public final class ParserContext {
 	}
 
 	public CompositeComponentDefinition getContainingComponent() {
-		return (!this.containingComponents.isEmpty() ?
-				(CompositeComponentDefinition) this.containingComponents.lastElement() : null);
+		return (!this.containingComponents.isEmpty() ? this.containingComponents.lastElement() : null);
 	}
 
 	public void pushContainingComponent(CompositeComponentDefinition containingComponent) {
@@ -99,7 +98,7 @@ public final class ParserContext {
 	}
 
 	public CompositeComponentDefinition popContainingComponent() {
-		return (CompositeComponentDefinition) this.containingComponents.pop();
+		return this.containingComponents.pop();
 	}
 
 	public void popAndRegisterContainingComponent() {

spring-context-support/src/main/java/org/springframework/cache/jcache/interceptor/CacheResolverAdapter.java

@@ -1,5 +1,20 @@
-package org.springframework.cache.jcache.interceptor;
+/*
+ * Copyright 2002-2018 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.cache.jcache.interceptor;
 
 import java.util.Collection;
 import java.util.Collections;
@@ -23,17 +38,19 @@ class CacheResolverAdapter implements CacheResolver {
 
 	private final javax.cache.annotation.CacheResolver target;
 
+
 	/**
 	 * Create a new instance with the JSR-107 cache resolver to invoke.
 	 */
 	public CacheResolverAdapter(javax.cache.annotation.CacheResolver target) {
-		Assert.notNull(target, "JSR-107 cache resolver must be set.");
+		Assert.notNull(target, "JSR-107 CacheResolver is required");
 		this.target = target;
 	}
 
+
 	/**
-	 * Return the underlying {@link javax.cache.annotation.CacheResolver} that this
-	 * instance is using.
+	 * Return the underlying {@link javax.cache.annotation.CacheResolver}
+	 * that this instance is using.
 	 */
 	protected javax.cache.annotation.CacheResolver getTarget() {
 		return target;
@@ -45,8 +62,10 @@ class CacheResolverAdapter implements CacheResolver {
 			throw new IllegalStateException("Unexpected context " + context);
 		}
 		CacheInvocationContext<?> cacheInvocationContext = (CacheInvocationContext<?>) context;
-		javax.cache.Cache<Object, Object> cache = target.resolveCache(cacheInvocationContext);
-		Assert.notNull(cache, "Cannot resolve cache for '" + context + "' using '" + target + "'");
+		javax.cache.Cache<Object, Object> cache = this.target.resolveCache(cacheInvocationContext);
+		if (cache == null) {
+			throw new IllegalStateException("Could not resolve cache for " + context + " using " + this.target);
+		}
 		return Collections.singleton(new JCacheCache(cache));
 	}
 

spring-context-support/src/test/java/org/springframework/cache/jcache/interceptor/CacheResolverAdapterTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -58,7 +58,7 @@ public class CacheResolverAdapterTests extends AbstractJCacheTests {
 		DefaultCacheInvocationContext<?> dummyContext = createDummyContext();
 		CacheResolverAdapter adapter = new CacheResolverAdapter(getCacheResolver(dummyContext, null));
 
-		thrown.expect(IllegalArgumentException.class);
+		thrown.expect(IllegalStateException.class);
 		adapter.resolveCaches(dummyContext);
 	}
 

spring-context/src/main/java/org/springframework/cache/interceptor/CacheResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -34,6 +34,7 @@ public interface CacheResolver {
 	 * Return the cache(s) to use for the specified invocation.
 	 * @param context the context of the particular invocation
 	 * @return the cache(s) to use (never {@code null})
+	 * @throws IllegalStateException if cache resolution failed
 	 */
 	Collection<? extends Cache> resolveCaches(CacheOperationInvocationContext<?> context);
 

spring-context/src/main/java/org/springframework/validation/AbstractErrors.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -211,7 +211,6 @@ public abstract class AbstractErrors implements Errors, Serializable {
 		return (!fieldErrors.isEmpty() ? fieldErrors.get(0) : null);
 	}
 
-
 	@Override
 	public Class<?> getFieldType(String field) {
 		Object value = getFieldValue(field);

spring-core/src/main/java/org/springframework/core/ParameterizedTypeReference.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -24,14 +24,14 @@ import org.springframework.util.Assert;
 /**
  * The purpose of this class is to enable capturing and passing a generic
  * {@link Type}. In order to capture the generic type and retain it at runtime,
- * you need to create a subclass as follows:
+ * you need to create a subclass (ideally as anonymous inline class) as follows:
  *
  * <pre class="code">
  * ParameterizedTypeReference&lt;List&lt;String&gt;&gt; typeRef = new ParameterizedTypeReference&lt;List&lt;String&gt;&gt;() {};
  * </pre>
  *
- * <p>The resulting {@code typeReference} instance can then be used to obtain a
- * {@link Type} instance that carries parameterized type information.
+ * <p>The resulting {@code typeRef} instance can then be used to obtain a {@link Type}
+ * instance that carries the captured parameterized type information at runtime.
  * For more information on "super type tokens" see the link to Neal Gafter's blog post.
  *
  * @author Arjen Poutsma
@@ -49,8 +49,9 @@ public abstract class ParameterizedTypeReference<T> {
 		Type type = parameterizedTypeReferenceSubclass.getGenericSuperclass();
 		Assert.isInstanceOf(ParameterizedType.class, type, "Type must be a parameterized type");
 		ParameterizedType parameterizedType = (ParameterizedType) type;
-		Assert.isTrue(parameterizedType.getActualTypeArguments().length == 1, "Number of type arguments must be 1");
-		this.type = parameterizedType.getActualTypeArguments()[0];
+		Type[] actualTypeArguments = parameterizedType.getActualTypeArguments();
+		Assert.isTrue(actualTypeArguments.length == 1, "Number of type arguments must be 1");
+		this.type = actualTypeArguments[0];
 	}
 
 	private ParameterizedTypeReference(Type type) {

spring-core/src/main/java/org/springframework/util/xml/TransformerUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -22,8 +22,8 @@ import javax.xml.transform.Transformer;
 import org.springframework.util.Assert;
 
 /**
- * Contains common behavior relating to {@link javax.xml.transform.Transformer Transformers}, and the
- * {@code javax.xml.transform} package in general.
+ * Contains common behavior relating to {@link javax.xml.transform.Transformer Transformers}
+ * and the {@code javax.xml.transform} package in general.
  *
  * @author Rick Evans
  * @author Juergen Hoeller
@@ -32,16 +32,16 @@ import org.springframework.util.Assert;
 public abstract class TransformerUtils {
 
 	/**
-	 * The indent amount of characters if {@link #enableIndenting(javax.xml.transform.Transformer) indenting is enabled}.
+	 * The indent amount of characters if {@link #enableIndenting indenting is enabled}.
 	 * <p>Defaults to "2".
 	 */
 	public static final int DEFAULT_INDENT_AMOUNT = 2;
 
+
 	/**
-	 * Enable indenting for the supplied {@link javax.xml.transform.Transformer}. <p>If the underlying XSLT engine is
-	 * Xalan, then the special output key {@code indent-amount} will be also be set to a value of {@link
-	 * #DEFAULT_INDENT_AMOUNT} characters.
-	 *
+	 * Enable indenting for the supplied {@link javax.xml.transform.Transformer}.
+	 * <p>If the underlying XSLT engine is Xalan, then the special output key {@code indent-amount}
+	 * will be also be set to a value of {@link #DEFAULT_INDENT_AMOUNT} characters.
 	 * @param transformer the target transformer
 	 * @see javax.xml.transform.Transformer#setOutputProperty(String, String)
 	 * @see javax.xml.transform.OutputKeys#INDENT
@@ -51,10 +51,9 @@ public abstract class TransformerUtils {
 	}
 
 	/**
-	 * Enable indenting for the supplied {@link javax.xml.transform.Transformer}. <p>If the underlying XSLT engine is
-	 * Xalan, then the special output key {@code indent-amount} will be also be set to a value of {@link
-	 * #DEFAULT_INDENT_AMOUNT} characters.
-	 *
+	 * Enable indenting for the supplied {@link javax.xml.transform.Transformer}.
+	 * <p>If the underlying XSLT engine is Xalan, then the special output key {@code indent-amount}
+	 * will be also be set to a value of {@link #DEFAULT_INDENT_AMOUNT} characters.
 	 * @param transformer  the target transformer
 	 * @param indentAmount the size of the indent (2 characters, 3 characters, etc.)
 	 * @see javax.xml.transform.Transformer#setOutputProperty(String, String)
@@ -62,7 +61,9 @@ public abstract class TransformerUtils {
 	 */
 	public static void enableIndenting(Transformer transformer, int indentAmount) {
 		Assert.notNull(transformer, "Transformer must not be null");
-		Assert.isTrue(indentAmount > -1, "The indent amount cannot be less than zero : got " + indentAmount);
+		if (indentAmount < 0) {
+			throw new IllegalArgumentException("The indent amount cannot be less than zero : got " + indentAmount);
+		}
 		transformer.setOutputProperty(OutputKeys.INDENT, "yes");
 		try {
 			// Xalan-specific, but this is the most common XSLT engine in any case
@@ -74,7 +75,6 @@ public abstract class TransformerUtils {
 
 	/**
 	 * Disable indenting for the supplied {@link javax.xml.transform.Transformer}.
-	 *
 	 * @param transformer the target transformer
 	 * @see javax.xml.transform.OutputKeys#INDENT
 	 */

spring-messaging/src/main/java/org/springframework/messaging/converter/AbstractMessageConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -135,8 +135,9 @@ public abstract class AbstractMessageConverter implements SmartMessageConverter
 	 * @param payloadClass either byte[] or String
 	 */
 	public void setSerializedPayloadClass(Class<?> payloadClass) {
-		Assert.isTrue(byte[].class == payloadClass || String.class == payloadClass,
-				"Payload class must be byte[] or String: " + payloadClass);
+		if (!(byte[].class == payloadClass || String.class == payloadClass)) {
+			throw new IllegalArgumentException("Payload class must be byte[] or String: " + payloadClass);
+		}
 		this.serializedPayloadClass = payloadClass;
 	}
 

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/support/HeadersMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -25,7 +25,6 @@ import org.springframework.messaging.MessageHeaders;
 import org.springframework.messaging.handler.annotation.Headers;
 import org.springframework.messaging.handler.invocation.HandlerMethodArgumentResolver;
 import org.springframework.messaging.support.MessageHeaderAccessor;
-import org.springframework.util.Assert;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -45,15 +44,12 @@ public class HeadersMethodArgumentResolver implements HandlerMethodArgumentResol
 	public boolean supportsParameter(MethodParameter parameter) {
 		Class<?> paramType = parameter.getParameterType();
 		return ((parameter.hasParameterAnnotation(Headers.class) && Map.class.isAssignableFrom(paramType)) ||
-				MessageHeaders.class == paramType ||
-				MessageHeaderAccessor.class.isAssignableFrom(paramType));
+				MessageHeaders.class == paramType || MessageHeaderAccessor.class.isAssignableFrom(paramType));
 	}
 
 	@Override
 	public Object resolveArgument(MethodParameter parameter, Message<?> message) throws Exception {
-
 		Class<?> paramType = parameter.getParameterType();
-
 		if (Map.class.isAssignableFrom(paramType)) {
 			return message.getHeaders();
 		}
@@ -68,7 +64,10 @@ public class HeadersMethodArgumentResolver implements HandlerMethodArgumentResol
 			}
 			else {
 				Method method = ReflectionUtils.findMethod(paramType, "wrap", Message.class);
-				Assert.notNull(method, "Cannot create accessor of type " + paramType + " for message " +  message);
+				if (method == null) {
+					throw new IllegalStateException(
+							"Cannot create accessor of type " + paramType + " for message " + message);
+				}
 				return ReflectionUtils.invokeMethod(method, null, message);
 			}
 		}

spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/HandlerMethodArgumentResolverComposite.java

@@ -24,7 +24,6 @@ import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.core.MethodParameter;
 import org.springframework.messaging.Message;
-import org.springframework.util.Assert;
 
 /**
  * Resolves method parameters by delegating to a list of registered
@@ -106,9 +105,10 @@ public class HandlerMethodArgumentResolverComposite implements HandlerMethodArgu
 	 */
 	@Override
 	public Object resolveArgument(MethodParameter parameter, Message<?> message) throws Exception {
-
 		HandlerMethodArgumentResolver resolver = getArgumentResolver(parameter);
-		Assert.notNull(resolver, "Unknown parameter type [" + parameter.getParameterType().getName() + "]");
+		if (resolver == null) {
+			throw new IllegalStateException("Unknown parameter type [" + parameter.getParameterType().getName() + "]");
+		}
 		return resolver.resolveArgument(parameter, message);
 	}
 

spring-oxm/src/main/java/org/springframework/oxm/jaxb/Jaxb2Marshaller.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -554,9 +554,12 @@ public class Jaxb2Marshaller implements MimeMarshaller, MimeUnmarshaller, Generi
 		XMLReader xmlReader = XMLReaderFactory.createXMLReader();
 		xmlReader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
 		for (int i = 0; i < resources.length; i++) {
-			Assert.notNull(resources[i], "Resource is null");
-			Assert.isTrue(resources[i].exists(), "Resource " + resources[i] + " does not exist");
-			InputSource inputSource = SaxResourceUtils.createInputSource(resources[i]);
+			Resource resource = resources[i];
+			Assert.notNull(resource, "Resource is null");
+			if (!resource.exists()) {
+				throw new IllegalArgumentException("Resource " + resource + " does not exist");
+			}
+			InputSource inputSource = SaxResourceUtils.createInputSource(resource);
 			schemaSources[i] = new SAXSource(xmlReader, inputSource);
 		}
 		SchemaFactory schemaFactory = SchemaFactory.newInstance(schemaLanguage);
@@ -1031,12 +1034,12 @@ public class Jaxb2Marshaller implements MimeMarshaller, MimeUnmarshaller, Generi
 		}
 
 		@Override
-		public InputStream getInputStream() throws IOException {
+		public InputStream getInputStream() {
 			return new ByteArrayInputStream(this.data, this.offset, this.length);
 		}
 
 		@Override
-		public OutputStream getOutputStream() throws IOException {
+		public OutputStream getOutputStream() {
 			throw new UnsupportedOperationException();
 		}
 

spring-web/src/main/java/org/springframework/web/util/HtmlCharacterEntityReferences.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -23,8 +23,6 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
 
-import org.springframework.util.Assert;
-
 /**
  * Represents a set of character entity references defined by the
  * HTML 4.0 standard.
@@ -87,8 +85,9 @@ class HtmlCharacterEntityReferences {
 		while (keys.hasMoreElements()) {
 			String key = (String) keys.nextElement();
 			int referredChar = Integer.parseInt(key);
-			Assert.isTrue((referredChar < 1000 || (referredChar >= 8000 && referredChar < 10000)),
-					"Invalid reference to special HTML entity: " + referredChar);
+			if (!(referredChar < 1000 || (referredChar >= 8000 && referredChar < 10000))) {
+				throw new IllegalArgumentException("Invalid reference to special HTML entity: " + referredChar);
+			}
 			int index = (referredChar < 1000 ? referredChar : referredChar - 7000);
 			String reference = entityReferences.getProperty(key);
 			this.characterToEntityReferenceMap[index] = REFERENCE_START + reference + REFERENCE_END;
@@ -119,14 +118,14 @@ class HtmlCharacterEntityReferences {
 	}
 
 	/**
-	 * Return the reference mapped to the given character or {@code null}.
+	 * Return the reference mapped to the given character, or {@code null} if none found.
 	 */
 	public String convertToReference(char character) {
 	   return convertToReference(character, WebUtils.DEFAULT_CHARACTER_ENCODING);
 	}
 
 	/**
-	 * Return the reference mapped to the given character or {@code null}.
+	 * Return the reference mapped to the given character, or {@code null} if none found.
 	 * @since 4.1.2
 	 */
 	public String convertToReference(char character, String encoding) {