JMS&MQ系统之Spring中嵌入ActiveMQ

在Spring中嵌入ActiveMQ有四种方式：纯Spring配置文件、使用Spring的配置文件并引入ActiveMQ的配置文件、使用硬代码及ActiveMQ配置文件和在Spring配置文件中使用特定的schema

1. 纯Spring配置文件

所谓纯Spring配置文件，就是直接在Spring的配置文件中配置ActiveMQ，代码如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<!-- 其他Spring配置 -->

<bean id="admins" class="org.apache.activemq.security.AuthenticationUser">
<constructor-arg index="0" value="admin" />
<constructor-arg index="1" value="password" />
<constructor-arg index="2" value="admins,publishers,consumers" />
</bean>
<bean id="publishers" class="org.apache.activemq.security.AuthenticationUser">
<constructor-arg index="0" value="publisher" />
<constructor-arg index="1" value="password" />
<constructor-arg index="2" value="publishers,consumers" />
</bean>
<bean id="consumers" class="org.apache.activemq.security.AuthenticationUser">
<constructor-arg index="0" value="consumer" />
<constructor-arg index="1" value="password" />
<constructor-arg index="2" value="consumers" />
</bean>
<bean id="guests" class="org.apache.activemq.security.AuthenticationUser">
<constructor-arg index="0" value="guest" />
<constructor-arg index="1" value="password" />
<constructor-arg index="2" value="guests" />
</bean>
<bean id="simpleAuthPlugin" class="org.apache.activemq.security.SimpleAuthenticationPlugin">
<property name="users">
<list>
<ref bean="admins" />
<ref bean="publishers" />
<ref bean="consumers" />
<ref bean="guests" />
</list>
</property>
</bean>
<bean id="broker" class="org.apache.activemq.broker.BrokerService" init-method="start" destroy-method="stop">
<property name="brokerName" value="myBroker" />
<property name="persistent" value="false" />
<property name="transportConnectorURIs">
<list>
<value>tcp://localhost:61616</value>
</list>
</property>
<property name="plugins">
<list>
<ref bean="simpleAuthPlugin" />
</list>
</property>
</bean>
</beans>

如果你看过JMS&MQ系列之普通Java程序中加载配置，你肯定可以马上将这一段代码与ActiveMQ的配置文件对应起来。

2. 使用Spring的配置文件并引入ActiveMQ的配置文件

ActiveMQ的配置文件不再赘述，Spring的配置文件如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<!-- 其他Spring配置 -->

<bean id="broker" class="org.apache.activemq.xbean.BrokerFactoryBean">
<property name="config" value="activemq.xml" />
<property name="start" value="true"></property>
</bean>
</beans>

3. 使用硬代码及ActiveMQ配置文件。使用这种方式时，若ActiveMQ已被创建，则不能再次被创建。activemq.xml文件的内容不再赘述，硬代码如下所示：

/**
*
* @author geloin
* @date 2012-9-12 下午3:42:55
*/
package com.geloin.activemq.test2;

import java.util.Hashtable;
import java.util.Map;

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MapMessage;
import javax.jms.Message;
import javax.jms.MessageProducer;
import javax.jms.Session;

import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.xbean.spring.context.FileSystemXmlApplicationContext;

/**
*
* @author geloin
* @date 2012-9-12 下午3:42:55
*/
public class MyConfiguration3 {

private int MAX_DELTA_PERCENT = 1;
private Map<String, Double> LAST_PRICES = new Hashtable<String, Double>();

private static String brokerURL = "tcp://localhost:61616";
private static transient ConnectionFactory factory;
private transient Connection connection;
private transient Session session;
private transient MessageProducer producer;

private String username = "publisher";
private String password = "password";

/**
* 发送消息
*
* @author geloin
* @date 2012-9-12 下午3:56:11
* @param stocks
* @throws JMSException
*/
private void sendMessage(String[] stocks) throws JMSException {
// 随机选择某一项作为消息主题
int idx = 0;
while (true) {
idx = (int) Math.round(stocks.length * Math.random());
if (idx < stocks.length) {
break;
}
}
String stock = stocks[idx];

// 目的
Destination destination = session.createTopic("STOCKS." + stock);

// 消息内容
Message message = createStockMessage(stock, session);

// 发送消息
producer.send(destination, message);

}

/**
* 创建消息内容
*
* @author geloin
* @date 2012-9-12 下午3:58:09
* @param stock
* @param session
* @return
* @throws JMSException
*/
private Message createStockMessage(String stock, Session session)
throws JMSException {
Double value = LAST_PRICES.get(stock);
if (value == null) {
value = new Double(Math.random() * 100);
}

// lets mutate the value by some percentage
double oldPrice = value.doubleValue();
value = new Double(mutatePrice(oldPrice));
LAST_PRICES.put(stock, value);
double price = value.doubleValue();

double offer = price * 1.001;

boolean up = (price > oldPrice);
MapMessage message = session.createMapMessage();
message.setString("stock", stock);
message.setDouble("price", price);
message.setDouble("offer", offer);
message.setBoolean("up", up);
return message;
}

private double mutatePrice(double price) {
double percentChange = (2 * Math.random() * MAX_DELTA_PERCENT)
- MAX_DELTA_PERCENT;

return price * (100 + percentChange) / 100;
}

/**
* 构造子
*
* @author geloin
* @date 2012-9-12 下午3:55:36
* @throws Exception
*/
public MyConfiguration3() throws Exception {
factory = new ActiveMQConnectionFactory(brokerURL);
connection = factory.createConnection(username, password);
connection.start();
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
producer = session.createProducer(null);
}

/**
*
* @author geloin
* @date 2012-9-12 下午3:42:55
* @param args
*/
public static void main(String[] args) throws Exception {
String configUri = MyConfiguration3.class.getResource("/")
+ "activemq.xml";
System.setProperty("activemq.base", System.getProperty("user.dir"));
new FileSystemXmlApplicationContext(configUri);
MyConfiguration3 cfg = new MyConfiguration3();
for (int i = 0; i < 10; i++) {
cfg.sendMessage(new String[] { "JAVA", "IONA" });
}
}
}

请关注主方法main，你会发现第一、二行代码已在JMS&MQ系列之普通Java程序中加载配置中阐述，直接跳过，看new FileSystemXmlApplicationContext(configUri)，这段代码的作用是设置当前程序运行过程中的上下文，此上下文直接作用下以后的代码。

4. 在Spring配置文件中使用特定的Schema

这一种方式与使用纯Spring配置文件类似，与其不同的是在Schema列表中加入了ActiveMQ的Schema，允许以非bean的形式配置ActiveMQ，代码如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:amq="http://activemq.apache.org/schema/core"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://activemq.apache.org/schema/core http://activemq.apache.org/schema/core/activemq-core.xsd
">

<!-- 其他Spring配置 -->

<amq:broker brokerName="myBroker" dataDirectory="${activemq.base}/data">
<amq:transportConnectors>
<amq:transportConnector name="openwire" uri="tcp://localhost:61616" />
</amq:transportConnectors>
<amq:plugins>
<amq:simpleAuthenticationPlugin>
<amq:users>
<amq:authenticationUser username="admin" password="password" groups="admins,publishers,consumers" />
<amq:authenticationUser username="publisher" password="password" groups="publishers,consumers" />
<amq:authenticationUser username="consumer" password="password" groups="consumers" />
<amq:authenticationUser username="guest" password="password" groups="guests" />
</amq:users>
</amq:simpleAuthenticationPlugin>
</amq:plugins>
</amq:broker>
</beans>

该配置文件的大部分并无特别，注意红色字体部分，即Schema部分即可。