ActiveMQ的Broker
一、是什么
- Broker相当于一个ActiveMQ服务器实例
- 实现了用代码的形式启动ActiveMQ将MQ嵌入到Java代码中，以便随时用随时启动，在用的时候再去启动这样能节省了资源，也保证了可用性。
- 用ActiveMQ Broker作为独立的消息服务器来构建Java应用。ActiveMQ也支持在vm中通信基于嵌入的broker，能够无缝的集成其他java应用。
二、Java应用嵌入ActiveMQ
1.pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.qingsi.activemq</groupId>
<artifactId>activemq_test</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<!-- activemq所需要的jar包配置 -->
<groupId>org.apache.activemq</groupId>
<artifactId>activemq-all</artifactId>
<version>5.15.11</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.10.1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.xbean/xbean-spring -->
<dependency>
<groupId>org.apache.xbean</groupId>
<artifactId>xbean-spring</artifactId>
<version>4.15</version>
</dependency>
<!-- 下面是junit/logback等基础配置 -->
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.2.3</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.18</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
</project>
2.borker实现
package com.qingsi.activemq.Embed;
import org.apache.activemq.broker.BrokerService;
public class EmbedBroker {
public static void main(String[] args) throws Exception {
// ActiveMQ也支持在vm中通信基于嵌入的broker
BrokerService brokerService = new BrokerService();
brokerService.setUseJmx(true);
brokerService.addConnector("tcp://localhost:61616");
brokerService.start();
}
}
- 运行后，启动一个mini版的AcitveMQ
3.生产者
package com.qingsi.activemq;
import org.apache.activemq.ActiveMQConnectionFactory;
import javax.jms.*;
public class JmsProduce {
public static final String ACTIVEMQ_URL = "tcp://localhost:61616";
public static final String QUEUE_NAME = "queue01";
public static void main(String[] args) throws JMSException {
//1.创建连接工厂，按照给定的URL，采用默认的用户名密码
ActiveMQConnectionFactory activeMQConnectionFactory = new ActiveMQConnectionFactory(ACTIVEMQ_URL);
//2.通过连接工厂,获得connection并启动访问
Connection connection = activeMQConnectionFactory.createConnection();
connection.start();
//3.创建会话session
//两个参数transacted=事务,acknowledgeMode=确认模式(签收)
//开启事务需要commit
Session session = connection.createSession(true, Session.AUTO_ACKNOWLEDGE);
//4.创建目的地(具体是队列queue还是主题topic)
Queue queue = session.createQueue(QUEUE_NAME);
//5.创建消息的生产者,并设置不持久化消息
MessageProducer producer = session.createProducer(queue);
//6.通过使用消息生产者,生产三条消息,发送到MQ的队列里面
try {
for (int i = 0; i < 3; i++) {
TextMessage textMessage = session.createTextMessage("tx msg--" + i);
producer.send(textMessage);
}
//7.提交事务
session.commit();
System.out.println("消息发送完成");
} catch (Exception e) {
System.out.println("出现异常,消息回滚");
session.rollback();
} finally {
//8.关闭资源
producer.close();
session.close();
connection.close();
}
}
}
4.消费者
package com.qingsi.activemq;
import org.apache.activemq.ActiveMQConnectionFactory;
import javax.jms.*;
import java.io.IOException;
public class JmsConsumer {
public static final String ACTIVEMQ_URL = "tcp://localhost:61616";
public static final String QUEUE_NAME = "queue01";
public static void main(String[] args) throws JMSException, IOException {
//1.创建连接工厂，按照给定的URL，采用默认的用户名密码
ActiveMQConnectionFactory activeMQConnectionFactory = new ActiveMQConnectionFactory(ACTIVEMQ_URL);
//2.通过连接工厂,获得connection并启动访问
Connection connection = activeMQConnectionFactory.createConnection();
connection.start();
//3.创建会话session
//两个参数transacted=事务,acknowledgeMode=确认模式(签收)
//消费者开启了事务就必须手动提交，不然会重复消费消息
Session session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE);
//4.创建目的地(具体是队列queue还是主题topic)
Queue queue = session.createQueue(QUEUE_NAME);
//5.创建消息的消费者,指定消费哪一个队列里面的消息
MessageConsumer messageConsumer = session.createConsumer(queue);
//6.通过监听的方式消费消息
messageConsumer.setMessageListener(new MessageListener() {
@Override
public void onMessage(Message message) {
if (message instanceof TextMessage) {
try {
TextMessage textMessage = (TextMessage) message;
System.out.println("***消费者接收broker的消息: " + textMessage.getText());
// 手动签收
textMessage.acknowledge();
} catch (Exception e) {
System.out.println("出现异常，消费失败，放弃消费");
}
}
}
});
//7.关闭资源
System.in.read();
messageConsumer.close();
session.close();
connection.close();
}
}