org.apache.activemq.command.ActiveMQObjectMessage Maven / Gradle / Ivy
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/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.activemq.command;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.Serializable;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.InflaterInputStream;
import javax.jms.JMSException;
import javax.jms.ObjectMessage;
import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.util.ByteArrayInputStream;
import org.apache.activemq.util.ByteArrayOutputStream;
import org.apache.activemq.util.ByteSequence;
import org.apache.activemq.util.ClassLoadingAwareObjectInputStream;
import org.apache.activemq.util.JMSExceptionSupport;
import org.apache.activemq.wireformat.WireFormat;
/**
* An ObjectMessage object is used to send a message that
* contains a serializable object in the Java programming language ("Java
* object"). It inherits from the Message interface and adds a
* body containing a single reference to an object. Only
* Serializable Java objects can be used.
*
* If a collection of Java objects must be sent, one of the
* Collection classes provided since JDK 1.2 can be used.
*
* When a client receives an ObjectMessage, it is in read-only
* mode. If a client attempts to write to the message at this point, a
* MessageNotWriteableException is thrown. If
* clearBody is called, the message can now be both read from and
* written to.
*
* @openwire:marshaller code="26"
* @see javax.jms.Session#createObjectMessage()
* @see javax.jms.Session#createObjectMessage(Serializable)
* @see javax.jms.BytesMessage
* @see javax.jms.MapMessage
* @see javax.jms.Message
* @see javax.jms.StreamMessage
* @see javax.jms.TextMessage
*/
public class ActiveMQObjectMessage extends ActiveMQMessage implements ObjectMessage {
// TODO: verify classloader
public static final byte DATA_STRUCTURE_TYPE = CommandTypes.ACTIVEMQ_OBJECT_MESSAGE;
static final ClassLoader ACTIVEMQ_CLASSLOADER = ActiveMQObjectMessage.class.getClassLoader();
protected transient Serializable object;
public Message copy() {
ActiveMQObjectMessage copy = new ActiveMQObjectMessage();
copy(copy);
return copy;
}
private void copy(ActiveMQObjectMessage copy) {
ActiveMQConnection connection = getConnection();
if (connection == null || !connection.isObjectMessageSerializationDefered()) {
storeContent();
copy.object = null;
} else {
copy.object = object;
}
super.copy(copy);
}
@Override
public void storeContentAndClear() {
storeContent();
object = null;
}
@Override
public void storeContent() {
ByteSequence bodyAsBytes = getContent();
if (bodyAsBytes == null && object != null) {
try {
ByteArrayOutputStream bytesOut = new ByteArrayOutputStream();
OutputStream os = bytesOut;
ActiveMQConnection connection = getConnection();
if (connection != null && connection.isUseCompression()) {
compressed = true;
os = new DeflaterOutputStream(os);
}
DataOutputStream dataOut = new DataOutputStream(os);
ObjectOutputStream objOut = new ObjectOutputStream(dataOut);
objOut.writeObject(object);
objOut.flush();
objOut.reset();
objOut.close();
setContent(bytesOut.toByteSequence());
} catch (IOException ioe) {
throw new RuntimeException(ioe.getMessage(), ioe);
}
}
}
public byte getDataStructureType() {
return DATA_STRUCTURE_TYPE;
}
public String getJMSXMimeType() {
return "jms/object-message";
}
/**
* Clears out the message body. Clearing a message's body does not clear its
* header values or property entries.
*
* If this message body was read-only, calling this method leaves the
* message body in the same state as an empty body in a newly created
* message.
*
* @throws JMSException if the JMS provider fails to clear the message body
* due to some internal error.
*/
public void clearBody() throws JMSException {
super.clearBody();
this.object = null;
}
/**
* Sets the serializable object containing this message's data. It is
* important to note that an ObjectMessage contains a
* snapshot of the object at the time setObject() is called;
* subsequent modifications of the object will have no effect on the
* ObjectMessage body.
*
* @param newObject the message's data
* @throws JMSException if the JMS provider fails to set the object due to
* some internal error.
* @throws javax.jms.MessageFormatException if object serialization fails.
* @throws javax.jms.MessageNotWriteableException if the message is in
* read-only mode.
*/
public void setObject(Serializable newObject) throws JMSException {
checkReadOnlyBody();
this.object = newObject;
setContent(null);
ActiveMQConnection connection = getConnection();
if (connection == null || !connection.isObjectMessageSerializationDefered()) {
storeContent();
}
}
/**
* Gets the serializable object containing this message's data. The default
* value is null.
*
* @return the serializable object containing this message's data
* @throws JMSException
*/
public Serializable getObject() throws JMSException {
if (object == null && getContent() != null) {
try {
ByteSequence content = getContent();
InputStream is = new ByteArrayInputStream(content);
if (isCompressed()) {
is = new InflaterInputStream(is);
}
DataInputStream dataIn = new DataInputStream(is);
ClassLoadingAwareObjectInputStream objIn = new ClassLoadingAwareObjectInputStream(dataIn);
try {
object = (Serializable)objIn.readObject();
} catch (ClassNotFoundException ce) {
throw JMSExceptionSupport.create("Failed to build body from content. Serializable class not available to broker. Reason: " + ce, ce);
} finally {
dataIn.close();
}
} catch (IOException e) {
throw JMSExceptionSupport.create("Failed to build body from bytes. Reason: " + e, e);
}
}
return this.object;
}
@Override
public void beforeMarshall(WireFormat wireFormat) throws IOException {
super.beforeMarshall(wireFormat);
// may have initiated on vm transport with deferred marshalling
storeContent();
}
public void clearMarshalledState() throws JMSException {
super.clearMarshalledState();
this.object = null;
}
public void onMessageRolledBack() {
super.onMessageRolledBack();
// lets force the object to be deserialized again - as we could have
// changed the object
object = null;
}
@Override
public void compress() throws IOException {
storeContent();
super.compress();
}
public String toString() {
try {
getObject();
} catch (JMSException e) {
}
return super.toString();
}
}