Related polishing

Issue. SPR-11428
(cherry picked from commit 9c6df76)

Author: jhoeller

spring-web/src/main/java/org/springframework/web/method/HandlerMethodSelector.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.
@@ -37,9 +37,8 @@
 public abstract class HandlerMethodSelector {
 
 	/**
-	 * Selects handler methods for the given handler type. Callers of this method define handler methods
-	 * of interest through the {@link MethodFilter} parameter.
-	 *
+	 * Select handler methods for the given handler type.
+	 * <p>Callers define handler methods of interest through the {@link MethodFilter} parameter.
 	 * @param handlerType the handler type to search handler methods on
 	 * @param handlerMethodFilter a {@link MethodFilter} to help recognize handler methods of interest
 	 * @return the selected methods, or an empty set

spring-web/src/main/java/org/springframework/web/method/annotation/ExceptionHandlerMethodResolver.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.
@@ -43,14 +43,25 @@
  */
 public class ExceptionHandlerMethodResolver {
 
+	/**
+	 * A filter for selecting {@code @ExceptionHandler} methods.
+	 */
+	public final static MethodFilter EXCEPTION_HANDLER_METHODS = new MethodFilter() {
+		public boolean matches(Method method) {
+			return (AnnotationUtils.findAnnotation(method, ExceptionHandler.class) != null);
+		}
+	};
+
 	private static final Method NO_METHOD_FOUND = ClassUtils.getMethodIfAvailable(System.class, "currentTimeMillis");
 
+
 	private final Map<Class<? extends Throwable>, Method> mappedMethods =
 			new ConcurrentHashMap<Class<? extends Throwable>, Method>(16);
 
 	private final Map<Class<? extends Throwable>, Method> exceptionLookupCache =
 			new ConcurrentHashMap<Class<? extends Throwable>, Method>(16);
 
+
 	/**
 	 * A constructor that finds {@link ExceptionHandler} methods in the given type.
 	 * @param handlerType the type to introspect
@@ -63,30 +74,31 @@ public ExceptionHandlerMethodResolver(Class<?> handlerType) {
 		}
 	}
 
+
 	/**
 	 * Extract exception mappings from the {@code @ExceptionHandler} annotation
 	 * first and as a fall-back from the method signature.
 	 */
 	@SuppressWarnings("unchecked")
 	private List<Class<? extends Throwable>> detectExceptionMappings(Method method) {
 		List<Class<? extends Throwable>> result = new ArrayList<Class<? extends Throwable>>();
-
-		ExceptionHandler annotation = AnnotationUtils.findAnnotation(method, ExceptionHandler.class);
-		result.addAll(Arrays.asList(annotation.value()));
-
+		detectAnnotationExceptionMappings(method, result);
 		if (result.isEmpty()) {
 			for (Class<?> paramType : method.getParameterTypes()) {
 				if (Throwable.class.isAssignableFrom(paramType)) {
 					result.add((Class<? extends Throwable>) paramType);
 				}
 			}
 		}
-
 		Assert.notEmpty(result, "No exception types mapped to {" + method + "}");
-
 		return result;
 	}
 
+	protected void detectAnnotationExceptionMappings(Method method, List<Class<? extends Throwable>> result) {
+		ExceptionHandler annot = AnnotationUtils.findAnnotation(method, ExceptionHandler.class);
+		result.addAll(Arrays.asList(annot.value()));
+	}
+
 	private void addExceptionMapping(Class<? extends Throwable> exceptionType, Method method) {
 		Method oldMethod = this.mappedMethods.put(exceptionType, method);
 		if (oldMethod != null && !oldMethod.equals(method)) {
@@ -110,7 +122,16 @@ public boolean hasExceptionMappings() {
 	 * @return a method to handle the exception or {@code null}
 	 */
 	public Method resolveMethod(Exception exception) {
-		Class<? extends Exception> exceptionType = exception.getClass();
+		return resolveMethodByExceptionType(exception.getClass());
+	}
+
+	/**
+	 * Find a method to handle the given exception type. This can be useful if
+	 * an Exception instance is not available (example for tools).
+	 * @param exceptionType the exception type
+	 * @return a method to handle the exception or {@code null}
+	 */
+	public Method resolveMethodByExceptionType(Class<? extends Exception> exceptionType) {
 		Method method = this.exceptionLookupCache.get(exceptionType);
 		if (method == null) {
 			method = getMappedMethod(exceptionType);
@@ -131,21 +152,11 @@ private Method getMappedMethod(Class<? extends Exception> exceptionType) {
 		}
 		if (!matches.isEmpty()) {
 			Collections.sort(matches, new ExceptionDepthComparator(exceptionType));
-			return mappedMethods.get(matches.get(0));
+			return this.mappedMethods.get(matches.get(0));
 		}
 		else {
 			return null;
 		}
 	}
 
-	/**
-	 * A filter for selecting {@code @ExceptionHandler} methods.
-	 */
-	public final static MethodFilter EXCEPTION_HANDLER_METHODS = new MethodFilter() {
-
-		public boolean matches(Method method) {
-			return AnnotationUtils.findAnnotation(method, ExceptionHandler.class) != null;
-		}
-	};
-
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/AbstractRequestCondition.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.
@@ -28,20 +28,13 @@
  */
 public abstract class AbstractRequestCondition<T extends AbstractRequestCondition<T>> implements RequestCondition<T> {
 
-	/**
-	 * Return the discrete items a request condition is composed of.
-	 * For example URL patterns, HTTP request methods, param expressions, etc.
-	 * @return a collection of objects, never {@code null}
-	 */
-	protected abstract Collection<?> getContent();
-
 	@Override
-	public boolean equals(Object o) {
-		if (this == o) {
+	public boolean equals(Object obj) {
+		if (this == obj) {
 			return true;
 		}
-		if (o != null && getClass().equals(o.getClass())) {
-			AbstractRequestCondition<?> other = (AbstractRequestCondition<?>) o;
+		if (obj != null && getClass().equals(obj.getClass())) {
+			AbstractRequestCondition<?> other = (AbstractRequestCondition<?>) obj;
 			return getContent().equals(other.getContent());
 		}
 		return false;
@@ -66,6 +59,14 @@ public String toString() {
 		return builder.toString();
 	}
 
+
+	/**
+	 * Return the discrete items a request condition is composed of.
+	 * For example URL patterns, HTTP request methods, param expressions, etc.
+	 * @return a collection of objects, never {@code null}
+	 */
+	protected abstract Collection<?> getContent();
+
 	/**
 	 * The notation to use when printing discrete items of content.
 	 * For example " || " for URL patterns or " && " for param expressions.

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/CompositeRequestCondition.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.
@@ -20,7 +20,6 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
-
 import javax.servlet.http.HttpServletRequest;
 
 import org.springframework.util.Assert;
@@ -43,6 +42,7 @@ public class CompositeRequestCondition extends AbstractRequestCondition<Composit
 
 	private final RequestConditionHolder[] requestConditions;
 
+
 	/**
 	 * Create an instance with 0 or more {@code RequestCondition} types. It is
 	 * important to create {@code CompositeRequestCondition} instances with the
@@ -53,6 +53,11 @@ public CompositeRequestCondition(RequestCondition<?>... requestConditions) {
 		this.requestConditions = wrap(requestConditions);
 	}
 
+	private CompositeRequestCondition(RequestConditionHolder[] requestConditions) {
+		this.requestConditions = requestConditions;
+	}
+
+
 	private RequestConditionHolder[] wrap(RequestCondition<?>... rawConditions) {
 		RequestConditionHolder[] wrappedConditions = new RequestConditionHolder[rawConditions.length];
 		for (int i = 0; i < rawConditions.length; i++) {
@@ -61,10 +66,6 @@ private RequestConditionHolder[] wrap(RequestCondition<?>... rawConditions) {
 		return wrappedConditions;
 	}
 
-	private CompositeRequestCondition(RequestConditionHolder[] requestConditions) {
-		this.requestConditions = requestConditions;
-	}
-
 	/**
 	 * Whether this instance contains 0 conditions or not.
 	 */
@@ -128,8 +129,9 @@ else if (isEmpty()) {
 
 	private void assertNumberOfConditions(CompositeRequestCondition other) {
 		Assert.isTrue(getLength() == other.getLength(),
-				"Cannot combine CompositeRequestConditions with a different number of conditions. "
-					+ this.requestConditions + " and  " + other.requestConditions);
+				"Cannot combine CompositeRequestConditions with a different number of conditions. " +
+				ObjectUtils.nullSafeToString(this.requestConditions) + " and  " +
+				ObjectUtils.nullSafeToString(other.requestConditions));
 	}
 
 	/**

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/ConsumesRequestCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2011 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.
@@ -23,7 +23,6 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
-
 import javax.servlet.http.HttpServletRequest;
 
 import org.springframework.http.MediaType;
@@ -48,11 +47,12 @@ public final class ConsumesRequestCondition extends AbstractRequestCondition<Con
 
 	private final List<ConsumeMediaTypeExpression> expressions;
 
+
 	/**
 	 * Creates a new instance from 0 or more "consumes" expressions.
 	 * @param consumes expressions with the syntax described in
 	 * {@link RequestMapping#consumes()}; if 0 expressions are provided,
-	 * the condition will match to every request.
+	 * the condition will match to every request
 	 */
 	public ConsumesRequestCondition(String... consumes) {
 		this(consumes, null);
@@ -78,6 +78,7 @@ private ConsumesRequestCondition(Collection<ConsumeMediaTypeExpression> expressi
 		Collections.sort(this.expressions);
 	}
 
+
 	private static Set<ConsumeMediaTypeExpression> parseExpressions(String[] consumes, String[] headers) {
 		Set<ConsumeMediaTypeExpression> result = new LinkedHashSet<ConsumeMediaTypeExpression>();
 		if (headers != null) {
@@ -98,6 +99,7 @@ private static Set<ConsumeMediaTypeExpression> parseExpressions(String[] consume
 		return result;
 	}
 
+
 	/**
 	 * Return the contained MediaType expressions.
 	 */
@@ -149,12 +151,10 @@ public ConsumesRequestCondition combine(ConsumesRequestCondition other) {
 	 * request 'Content-Type' header and returns an instance that is guaranteed
 	 * to contain matching expressions only. The match is performed via
 	 * {@link MediaType#includes(MediaType)}.
-	 *
 	 * @param request the current request
-	 *
 	 * @return the same instance if the condition contains no expressions;
-	 * 		or a new condition with matching expressions only;
-	 * 		or {@code null} if no expressions match.
+	 * or a new condition with matching expressions only;
+	 * or {@code null} if no expressions match.
 	 */
 	public ConsumesRequestCondition getMatchingCondition(HttpServletRequest request) {
 		if (isEmpty()) {
@@ -173,11 +173,10 @@ public ConsumesRequestCondition getMatchingCondition(HttpServletRequest request)
 	/**
 	 * Returns:
 	 * <ul>
-	 * 	<li>0 if the two conditions have the same number of expressions
-	 * 	<li>Less than 0 if "this" has more or more specific media type expressions
-	 * 	<li>Greater than 0 if "other" has more or more specific media type expressions
+	 * <li>0 if the two conditions have the same number of expressions
+	 * <li>Less than 0 if "this" has more or more specific media type expressions
+	 * <li>Greater than 0 if "other" has more or more specific media type expressions
 	 * </ul>
-	 *
 	 * <p>It is assumed that both instances have been obtained via
 	 * {@link #getMatchingCondition(HttpServletRequest)} and each instance contains
 	 * the matching consumable media type expression only or is otherwise empty.
@@ -197,6 +196,7 @@ else if (other.expressions.isEmpty()) {
 		}
 	}
 
+
 	/**
 	 * Parses and matches a single media type expression to a request's 'Content-Type' header.
 	 */

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/HeadersRequestCondition.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.
@@ -20,7 +20,6 @@
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.Set;
-
 import javax.servlet.http.HttpServletRequest;
 
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -41,12 +40,13 @@ public final class HeadersRequestCondition extends AbstractRequestCondition<Head
 
 	private final Set<HeaderExpression> expressions;
 
+
 	/**
 	 * Create a new instance from the given header expressions. Expressions with
 	 * header names 'Accept' or 'Content-Type' are ignored. See {@link ConsumesRequestCondition}
 	 * and {@link ProducesRequestCondition} for those.
 	 * @param headers media type expressions with syntax defined in {@link RequestMapping#headers()};
-	 * 		if 0, the condition will match to every request.
+	 * if 0, the condition will match to every request
 	 */
 	public HeadersRequestCondition(String... headers) {
 		this(parseExpressions(headers));
@@ -56,6 +56,7 @@ private HeadersRequestCondition(Collection<HeaderExpression> conditions) {
 		this.expressions = Collections.unmodifiableSet(new LinkedHashSet<HeaderExpression>(conditions));
 	}
 
+
 	private static Collection<HeaderExpression> parseExpressions(String... headers) {
 		Set<HeaderExpression> expressions = new LinkedHashSet<HeaderExpression>();
 		if (headers != null) {
@@ -113,11 +114,10 @@ public HeadersRequestCondition getMatchingCondition(HttpServletRequest request)
 	/**
 	 * Returns:
 	 * <ul>
-	 * 	<li>0 if the two conditions have the same number of header expressions
-	 * 	<li>Less than 0 if "this" instance has more header expressions
-	 * 	<li>Greater than 0 if the "other" instance has more header expressions
+	 * <li>0 if the two conditions have the same number of header expressions
+	 * <li>Less than 0 if "this" instance has more header expressions
+	 * <li>Greater than 0 if the "other" instance has more header expressions
 	 * </ul>
-	 *
 	 * <p>It is assumed that both instances have been obtained via
 	 * {@link #getMatchingCondition(HttpServletRequest)} and each instance
 	 * contains the matching header expression only or is otherwise empty.
@@ -126,6 +126,7 @@ public int compareTo(HeadersRequestCondition other, HttpServletRequest request)
 		return other.expressions.size() - this.expressions.size();
 	}
 
+
 	/**
 	 * Parses and matches a single header expression to a request.
 	 */
@@ -158,4 +159,5 @@ public int hashCode() {
 			return result;
 		}
 	}
+
 }