diff --git a/spring-messaging/src/main/java/org/springframework/messaging/MessageHeaders.java b/spring-messaging/src/main/java/org/springframework/messaging/MessageHeaders.java
index 0f15080521f..02a73c18ff7 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/MessageHeaders.java
+++ b/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.
@@ -42,6 +42,7 @@ import org.springframework.util.IdGenerator;
* IMPORTANT: This class is immutable. Any mutating operation such as
* {@code put(..)}, {@code putAll(..)} and others will throw
* {@link UnsupportedOperationException}.
+ *
Subclasses do have access to the raw headers, however, via {@link #getRawHeaders()}.
*
* One way to create message headers is to use the
* {@link org.springframework.messaging.support.MessageBuilder MessageBuilder}:
@@ -66,7 +67,7 @@ import org.springframework.util.IdGenerator;
* @see org.springframework.messaging.support.MessageBuilder
* @see org.springframework.messaging.support.MessageHeaderAccessor
*/
-public final class MessageHeaders implements Map, Serializable {
+public class MessageHeaders implements Map, Serializable {
private static final long serialVersionUID = -4615750558355702881L;
@@ -95,13 +96,27 @@ public final class MessageHeaders implements Map, Serializable {
private final Map headers;
+ /**
+ * Constructs a minimal {@link MessageHeaders} with zero headers.
+ */
+ protected MessageHeaders() {
+ this.headers = new HashMap();
+ }
+ /**
+ * Consructs a {@link MessageHeaders} from the headers map; adding (or
+ * overwriting) the {@link #ID} and {@link #TIMESTAMP} headers.
+ * @param headers The map.
+ */
public MessageHeaders(Map headers) {
this.headers = (headers != null) ? new HashMap(headers) : new HashMap();
this.headers.put(ID, ((idGenerator != null) ? idGenerator : defaultIdGenerator).generateId());
this.headers.put(TIMESTAMP, System.currentTimeMillis());
}
+ protected Map getRawHeaders() {
+ return this.headers;
+ }
public UUID getId() {
return this.get(ID, UUID.class);
diff --git a/spring-messaging/src/test/java/org/springframework/messaging/MessageHeadersTests.java b/spring-messaging/src/test/java/org/springframework/messaging/MessageHeadersTests.java
index 7b7446caa8c..0c88c39f143 100644
--- a/spring-messaging/src/test/java/org/springframework/messaging/MessageHeadersTests.java
+++ b/spring-messaging/src/test/java/org/springframework/messaging/MessageHeadersTests.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.
@@ -23,6 +23,8 @@ import java.io.ObjectOutputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicLong;
import org.junit.Test;
@@ -32,6 +34,7 @@ import static org.junit.Assert.*;
* Test fixture for {@link MessageHeaders}.
*
* @author Rossen Stoyanchev
+ * @author Gary Russell
*/
public class MessageHeadersTests {
@@ -138,6 +141,21 @@ public class MessageHeadersTests {
assertNull(output.get("address"));
}
+ @Test
+ public void subclass() {
+ final AtomicLong id = new AtomicLong();
+ @SuppressWarnings("serial")
+ class MyMH extends MessageHeaders {
+
+ public MyMH() {
+ this.getRawHeaders().put(ID, new UUID(0, id.incrementAndGet()));
+ }
+
+ }
+ MessageHeaders headers = new MyMH();
+ assertEquals("00000000-0000-0000-0000-000000000001", headers.getId().toString());
+ assertEquals(1, headers.size());
+ }
private static Object serializeAndDeserialize(Object object) throws Exception {
ByteArrayOutputStream baos = new ByteArrayOutputStream();