ActiveMQ (
二) 使用Queue或者Topic发送/接受消息
本篇主要讲解在未使用其他框架(Spring)整合情况下,独立基于ActiveMQ,使用JMS规范进行消息通信。
一.JMS回顾
Java Message Service (JMS)是sun提出来的为J2EE提供企业消息处理的一套规范,JMS目前有2套规范还在使用JMS <chsdate year="1899" month="12" day="30" islunardate="False" isrocdate="False" w:st="on">1.0.2</chsdate>b和1.1. 1.1已经成为主流的JMS Provider事实上的标准了.
1.1主要在session上面有一些重要改变,比如支持建立同一session上的transaction,让他支持同时发送P2P(Queue)消息和接受
Topic消息。在JMS中间主要定义了2种消息模式Point-to-Point (点对点), Publich/Subscribe Model (发布/订阅者), 其中在Publich/Subscribe 模式下又有Nondurable subscription和durable subscription (持久化订阅)2种消息处理方式。
下面是JMS规范基本的接口和实现
JMS Common Interface PTP-Specific Interface Pub/Sub-specific interfaces
ConnectionFactory QueueConnectionFactory TopicConnectionFactory
Connection QueueConnection TopicConnection
Destination Queue Topic
Session QueueSession TopiSession
MessageProducer QueueSender TopicPublisher
MessageConsumerQueueReceiver/QueueBrwer TopicSubscriber 二.使用Queue
1. 下面以ActiveMQ example的代码为主进行说明
2. 使用ActiveMQ的Connection,ConnectionFactory 建立连接,注意这里没有用到pool
//建立Connection
1. protectedConnectioncreateConnection()throwsJMSException,Exception{
2. ActiveMQConnectionFactoryconnectionFactory=newActiveMQConnectionFactory(user,pwd,url);
3. Connectionconnection=connectionFactory.createConnection();
4. if(durable&&clientID!=null){
5. connection.setClientID(clientID);
6. }
7. connection.start();
8. returnconnection;
9. }
//建立Session
protectedSessioncreateSession(Connectionconnection)throwsException{
1. Sessionsession=connection.createSession(transacted,ackMode);
2. returnsession;
3. }
2。发送消息的代码
//建立QueueSessionprotectedMessageProducercreateProducer(Sessionsession)throwsJMSException{
1. Destincationdestination=session.createQueue("queue.hello");
2. MessageProducerproducer=session.createProducer(destination);
3. producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
4.
5. if(timeToLive!=0)
6. producer.setTimeToLive(timeToLive);
7. returnproducer;
8. }
//使用Producer发送消息到Queue
producer.send(message); 3。接受消息,在JMS规范里面,你可以使用
1. QueueReceiver/QueueBrowser直接接受消息,但是更多的情况下我们采用消息通知方式,即实现MessageListener接口
2. publicvoidonMessage(Messagemessage){
3. //processmessage
4. }
5.
6. //setMessageListner,receivemessage
7. Destincationdestination=session.createQueue("queue.hello");
8. consumer=session.createConsumer(destination);
9. consumer.setMessageListener(this);
以上就是使用jms queue发送接受消息的基本方式
三 Topic 1. 建立连接
java 代码
1. protectedConnectioncreateConnection()throwsJMSException,Exception{
2. ActiveMQConnectionFactoryconnectionFactory=newActiveMQConnectionFactory(user,pwd,url);
3. Connectionconnection=connectionFactory.createConnection();
4. //如果你要使用DurableSubScription方式,你必须为connection设置一个ClientID
5. if(durable&&clientID!=null){
6. connection.setClientID(clientID);
7. }
8. connection.start();
9. returnconnection;
10. }
2. 建立Session
java 代码
1. protectedSessioncreateSession(Connectionconnection)throwsException{
2. Sessionsession=connection.createSession(transacted,ackMode);
3. returnsession;
4. }
创建Producer 发送消息到Topic
//createtopiconsession
1. topic=session.createTopic("topic.hello");
2. producer=session.createProducer(topic);
3. //sendmessage
4. producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
5. producer.send(message);
创建Consumer接受消息(基本上和Queue相同)
1. Destincationdestination=session.createTopic("topic.hello");
2. MessageConsumerconsumer=session.createConsumer(destination);
3. consumer.setMessageListener(this);
4.
5. //如果你使用的是DurableSubscription方式,你必须在建立connection的时候
6. //设置ClientID,而且建立comsumer的时候使用createDurableSubscriber方法,为他指定一个consumerName。
7. //connection.setClientID(clientId);
8. //consumer=session.createDurableSubscriber((Topic)destination,consumerName);
四:连接ActiveMQ的方式
ActiveMQConnectionFactory 提供了多种连接到Broker的方式activemq.apache.org/uri-protocols.html常见的有
vm://host:port //vm
tcp://host:port //tcp
ssl://host:port //SSL
stomp://host:port //stomp协议可以跨语言,目前有很多种stomp client 库(java,c#,c/c++,ruby,python...);activemq例子代码发送Message消息
完整的示例程序:
发送TextMessage
public class SendMessage {
private static final String url = "tcp://localhost:61616";;
private static final String QUEUE_NAME = "choice.queue";
protected String expectedBody = "<hello>world!</hello>";
public void sendMessage() throws JMSException{
Connection connection = null;
try{
ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(url);
connection = connectionFactory.createConnection();
connection.start();
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue(QUEUE_NAME);
MessageProducer producer = session.createProducer(destination);
TextMessage message = session.createTextMessage(expectedBody);
message.setStringProperty("headname", "remoteB");
producer.send(message);
}catch(Exception e){
e.printStackTrace();
}finally{
connection.close();
}
}
*********************************************************************
发送BytesMessage
public class SendMessage {
private String url = "tcp://localhost:61616";
public void sendMessage() throws JMSException{
ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(url);
Connection connection = connectionFactory.createConnection();
connection.start();
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue("test.queue");
MessageProducer producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
BytesMessage message = session.createBytesMessage();
byte[] content = getFileByte("d://test.jar");
message.writeBytes(content);
try{
producer.send(message);
System.out.println("successful send message");
}catch(Exception e){
e.printStackTrace();
e.getMessage();
}finally{
session.close();
connection.close();
}
}
private byte[] getFileByte(String filename){
byte[] buffer = null;
FileInputStream fin = null;
try {
File file = new File(filename);
fin = new FileInputStream(file);
buffer = new byte[fin.available()];
fin.read(buffer);
} catch
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