Polishing

spring-core/src/main/java/org/springframework/util/comparator/package-info.java

@@ -1,3 +1,4 @@
+
 /**
  *
  * Useful generic {@code java.util.Comparator} implementations,

spring-core/src/main/java/org/springframework/util/concurrent/package-info.java

@@ -2,6 +2,7 @@
 /**
  *
  * Useful generic {@code java.util.concurrent.Future} extension.
+ *
  */
 package org.springframework.util.concurrent;
 

spring-messaging/src/main/java/org/springframework/messaging/Message.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -27,7 +27,7 @@ package org.springframework.messaging;
 public interface Message<T> {
 
 	/**
-	 * Return message headers for the message, never {@code null}.
+	 * Return message headers for the message (never {@code null}).
 	 */
 	MessageHeaders getHeaders();
 

spring-messaging/src/main/java/org/springframework/messaging/MessageHeaders.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -37,17 +37,19 @@ import org.springframework.util.AlternativeJdkIdGenerator;
 import org.springframework.util.IdGenerator;
 
 /**
- * The headers for a {@link Message}
- * <p>
- * <b>IMPORTANT</b>: This class is immutable. Any mutating operation such as
+ * The headers for a {@link Message}.
+ *
+ * <p><b>IMPORTANT</b>: This class is immutable. Any mutating operation such as
  * {@code put(..)}, {@code putAll(..)} and others will throw
  * {@link UnsupportedOperationException}.
- * <p>
- * One way to create message headers is to use the
+ * <p>Subclasses do have access to the raw headers, however, via {@link #getRawHeaders()}.
+ *
+ * <p>One way to create message headers is to use the
  * {@link org.springframework.messaging.support.MessageBuilder MessageBuilder}:
  * <pre class="code">
  * MessageBuilder.withPayload("foo").setHeader("key1", "value1").setHeader("key2", "value2");
  * </pre>
+ *
  * A second option is to create {@link org.springframework.messaging.support.GenericMessage}
  * passing a payload as {@link Object} and headers as a {@link Map java.util.Map}:
  * <pre class="code">
@@ -56,6 +58,7 @@ import org.springframework.util.IdGenerator;
  * headers.put("key2", "value2");
  * new GenericMessage("foo", headers);
  * </pre>
+ *
  * A third option is to use {@link org.springframework.messaging.support.MessageHeaderAccessor}
  * or one of its sub-classes to create specific categories of headers.
  *
@@ -98,7 +101,7 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 
 	public MessageHeaders(Map<String, Object> headers) {
 		this.headers = (headers != null) ? new HashMap<String, Object>(headers) : new HashMap<String, Object>();
-		this.headers.put(ID, ((idGenerator != null) ? idGenerator : defaultIdGenerator).generateId());
+		this.headers.put(ID, (idGenerator != null ? idGenerator : defaultIdGenerator).generateId());
 		this.headers.put(TIMESTAMP, System.currentTimeMillis());
 	}
 
@@ -133,20 +136,14 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 	}
 
 	@Override
-	public int hashCode() {
-		return this.headers.hashCode();
+	public boolean equals(Object other) {
+		return (this == other ||
+				(other instanceof MessageHeaders && this.headers.equals(((MessageHeaders) other).headers)));
 	}
 
 	@Override
-	public boolean equals(Object object) {
-		if (this == object) {
-			return true;
-		}
-		if (object != null && object instanceof MessageHeaders) {
-			MessageHeaders other = (MessageHeaders) object;
-			return this.headers.equals(other.headers);
-		}
-		return false;
+	public int hashCode() {
+		return this.headers.hashCode();
 	}
 
 	@Override
@@ -157,9 +154,8 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 		return map.toString();
 	}
 
-	/*
-	 * Map implementation
-	 */
+
+	// Map implementation
 
 	public boolean containsKey(Object key) {
 		return this.headers.containsKey(key);
@@ -193,7 +189,8 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 		return Collections.unmodifiableCollection(this.headers.values());
 	}
 
-	// Unsupported operations
+
+	// Unsupported Map operations
 
 	/**
 	 * Since MessageHeaders are immutable, the call to this method will result in {@link UnsupportedOperationException}.
@@ -223,6 +220,7 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 		throw new UnsupportedOperationException("MessageHeaders is immutable");
 	}
 
+
 	// Serialization methods
 
 	private void writeObject(ObjectOutputStream out) throws IOException {
@@ -234,7 +232,7 @@ public final class MessageHeaders implements Map<String, Object>, Serializable {
 		}
 		for (String key : keysToRemove) {
 			if (logger.isInfoEnabled()) {
-				logger.info("removing non-serializable header: " + key);
+				logger.info("Removing non-serializable header: " + key);
 			}
 			this.headers.remove(key);
 		}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -38,7 +38,7 @@ public interface MessageConverter {
 	 * conversion, it should return {@code null}.
 	 * @param message the input message
 	 * @param targetClass the target class for the conversion
-	 * @return the result of the conversion or {@code null} if the converter cannot
+	 * @return the result of the conversion, or {@code null} if the converter cannot
 	 * perform the conversion
 	 */
 	Object fromMessage(Message<?> message, Class<?> targetClass);

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -39,7 +39,7 @@ public class SimpleMessageConverter implements MessageConverter {
 		if (targetClass == null) {
 			return payload;
 		}
-		return ClassUtils.isAssignableValue(targetClass, payload) ? payload : null;
+		return (ClassUtils.isAssignableValue(targetClass, payload) ? payload : null);
 	}
 
 	@Override

spring-messaging/src/main/java/org/springframework/messaging/support/MessageBuilder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -23,14 +23,13 @@ import org.springframework.messaging.MessageChannel;
 import org.springframework.util.Assert;
 
 /**
- * A builder for creating a {@link GenericMessage} (or {@link ErrorMessage} if
- * the payload is of type {@link Throwable}).
+ * A builder for creating a {@link GenericMessage}
+ * (or {@link ErrorMessage} if the payload is of type {@link Throwable}).
  *
  * @author Arjen Poutsma
  * @author Mark Fisher
  * @author Rossen Stoyanchev
  * @since 4.0
- *
  * @see GenericMessage
  * @see ErrorMessage
  */
@@ -38,16 +37,13 @@ public final class MessageBuilder<T> {
 
 	private final T payload;
 
-	private MessageHeaderAccessor headerAccessor;
-
 	private final Message<T> originalMessage;
 
+	private MessageHeaderAccessor headerAccessor;
+
 
-	/**
-	 * Private constructor to be invoked from the static factory methods only.
-	 */
 	private MessageBuilder(T payload, Message<T> originalMessage) {
-		Assert.notNull(payload, "payload must not be null");
+		Assert.notNull(payload, "Payload must not be null");
 		this.payload = payload;
 		this.originalMessage = originalMessage;
 		this.headerAccessor = new MessageHeaderAccessor(originalMessage);
@@ -58,11 +54,10 @@ public final class MessageBuilder<T> {
 	 * Create a builder for a new {@link Message} instance pre-populated with all of the
 	 * headers copied from the provided message. The payload of the provided Message will
 	 * also be used as the payload for the new message.
-	 *
 	 * @param message the Message from which the payload and all headers will be copied
 	 */
 	public static <T> MessageBuilder<T> fromMessage(Message<T> message) {
-		Assert.notNull(message, "message must not be null");
+		Assert.notNull(message, "Message must not be null");
 		return new MessageBuilder<T>(message.getPayload(), message);
 	}
 
@@ -76,12 +71,12 @@ public final class MessageBuilder<T> {
 
 
 	/**
-	 * Set the message headers.
-	 * @param headerAccessor the headers for the message
+	 * Set the message headers to use by providing a {@code MessageHeaderAccessor}.
+	 * @param accessor the headers to use
 	 */
-	public MessageBuilder<T> setHeaders(MessageHeaderAccessor headerAccessor) {
-		Assert.notNull(headerAccessor, "HeaderAccessor must not be null");
-		this.headerAccessor = headerAccessor;
+	public MessageBuilder<T> setHeaders(MessageHeaderAccessor accessor) {
+		Assert.notNull(accessor, "MessageHeaderAccessor must not be null");
+		this.headerAccessor = accessor;
 		return this;
 	}
 
@@ -161,13 +156,15 @@ public final class MessageBuilder<T> {
 
 	@SuppressWarnings("unchecked")
 	public Message<T> build() {
-		if ((this.originalMessage != null) && !this.headerAccessor.isModified()) {
+		if (this.originalMessage != null && !this.headerAccessor.isModified()) {
 			return this.originalMessage;
 		}
 		if (this.payload instanceof Throwable) {
 			return (Message<T>) new ErrorMessage((Throwable) this.payload, this.headerAccessor.toMap());
 		}
-		return new GenericMessage<T>(this.payload, this.headerAccessor.toMap());
+		else {
+			return new GenericMessage<T>(this.payload, this.headerAccessor.toMap());
+		}
 	}
 
 }

spring-messaging/src/main/java/org/springframework/messaging/support/MessageHeaderAccessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 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.
@@ -25,10 +25,10 @@ import java.util.UUID;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.MessageHeaders;
-import org.springframework.util.Assert;
 import org.springframework.util.MimeType;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.PatternMatchUtils;
@@ -48,8 +48,7 @@ import org.springframework.util.StringUtils;
  */
 public class MessageHeaderAccessor {
 
-	protected Log logger = LogFactory.getLog(getClass());
-
+	protected final Log logger = LogFactory.getLog(getClass());
 
 	// wrapped read-only message headers
 	private final MessageHeaders originalHeaders;
@@ -69,7 +68,7 @@ public class MessageHeaderAccessor {
 	 * A constructor for accessing and modifying existing message headers.
 	 */
 	public MessageHeaderAccessor(Message<?> message) {
-		this.originalHeaders = (message != null) ? message.getHeaders() : null;
+		this.originalHeaders = (message != null ? message.getHeaders() : null);
 	}
 
 
@@ -109,23 +108,37 @@ public class MessageHeaderAccessor {
 	}
 
 	/**
-	 * Set the value for the given header name. If the provided value is {@code null} the
-	 * header will be removed.
+	 * Set the value for the given header name.
+	 * <p>If the provided value is {@code null}, the header will be removed.
 	 */
 	public void setHeader(String name, Object value) {
-		Assert.isTrue(!isReadOnly(name), "The '" + name + "' header is read-only.");
+		if (isReadOnly(name)) {
+			throw new IllegalArgumentException("'" + name + "' header is read-only");
+		}
 		verifyType(name, value);
 		if (!ObjectUtils.nullSafeEquals(value, getHeader(name))) {
 			this.headers.put(name, value);
 		}
 	}
 
+	protected void verifyType(String headerName, Object headerValue) {
+		if (headerName != null && headerValue != null) {
+			if (MessageHeaders.ERROR_CHANNEL.equals(headerName) || MessageHeaders.REPLY_CHANNEL.endsWith(headerName)) {
+				if (!(headerValue instanceof MessageChannel || headerValue instanceof String)) {
+					throw new IllegalArgumentException(
+							"'" + headerName + "' header value must be a MessageChannel or String");
+				}
+			}
+		}
+	}
+
 	protected boolean isReadOnly(String headerName) {
 		return MessageHeaders.ID.equals(headerName) || MessageHeaders.TIMESTAMP.equals(headerName);
 	}
 
 	/**
-	 * Set the value for the given header name only if the header name is not already associated with a value.
+	 * Set the value for the given header name only if the header name is not
+	 * already associated with a value.
 	 */
 	public void setHeaderIfAbsent(String name, Object value) {
 		if (getHeader(name) == null) {
@@ -134,9 +147,9 @@ public class MessageHeaderAccessor {
 	}
 
 	/**
-	 * Removes all headers provided via array of 'headerPatterns'. As the name suggests
-	 * the array may contain simple matching patterns for header names. Supported pattern
-	 * styles are: "xxx*", "*xxx", "*xxx*" and "xxx*yyy".
+	 * Removes all headers provided via array of 'headerPatterns'.
+	 * <p>As the name suggests, array may contain simple matching patterns for header
+	 * names. Supported pattern styles are: "xxx*", "*xxx", "*xxx*" and "xxx*yyy".
 	 */
 	public void removeHeaders(String... headerPatterns) {
 		List<String> headersToRemove = new ArrayList<String>();
@@ -178,9 +191,9 @@ public class MessageHeaderAccessor {
 	}
 
 	/**
-	 * Copy the name-value pairs from the provided Map. This operation will overwrite any
-	 * existing values. Use { {@link #copyHeadersIfAbsent(Map)} to avoid overwriting
-	 * values.
+	 * Copy the name-value pairs from the provided Map.
+	 * <p>This operation will overwrite any existing values. Use
+	 * {@link #copyHeadersIfAbsent(Map)} to avoid overwriting values.
 	 */
 	public void copyHeaders(Map<String, ?> headersToCopy) {
 		if (headersToCopy != null) {
@@ -194,8 +207,8 @@ public class MessageHeaderAccessor {
 	}
 
 	/**
-	 * Copy the name-value pairs from the provided Map. This operation will <em>not</em>
-	 * overwrite any existing values.
+	 * Copy the name-value pairs from the provided Map.
+	 * <p>This operation will <em>not</em> overwrite any existing values.
 	 */
 	public void copyHeadersIfAbsent(Map<String, ?> headersToCopy) {
 		if (headersToCopy != null) {
@@ -251,17 +264,8 @@ public class MessageHeaderAccessor {
 
 	@Override
 	public String toString() {
-		return getClass().getSimpleName() + " [originalHeaders=" + this.originalHeaders
-				+ ", updated headers=" + this.headers + "]";
+		return getClass().getSimpleName() + " [originalHeaders=" + this.originalHeaders +
+				", updated headers=" + this.headers + "]";
 	}
 
-	protected void verifyType(String headerName, Object headerValue) {
-        if (headerName != null && headerValue != null) {
-        	if (MessageHeaders.ERROR_CHANNEL.equals(headerName)
-                    || MessageHeaders.REPLY_CHANNEL.endsWith(headerName)) {
-                Assert.isTrue(headerValue instanceof MessageChannel || headerValue instanceof String, "The '"
-                        + headerName + "' header value must be a MessageChannel or String.");
-            }
-        }
-    }
 }