Spring线程池开发实战

Spring线程池开发实战

本文提供了三个Spring多线程开发的例子，由浅入深，由于例子一目了然，所以并未做过多的解释。诸位一看便知。

前提条件：

1）在Eclipse创建一个Java项目，我取名为SpringThreadDemo。

2）项目所需的JAR包如图所示：

下面开始。

注：项目源码已经托管到GitHub，地址：https://github.com/chszs/SpringThreadDemo

例子1：Spring结合Java线程。

通过继承Thread创建一个简单的Java线程，然后使用@Component让Spring容器管理此线程，Bean的范围必须是prototype，因此每个请求都会返回一个新实例，运行每个单独的线程。

PrintThread.java

    package com.chszs.thread;
    
    import org.springframework.stereotype.Component;
    import org.springframework.context.annotation.Scope;
    
    @Component
    @Scope("prototype")
    public class PrintThread extends Thread{
            @Override
            public void run(){
                    System.out.println(getName() + " is running.");
                    try{
                            Thread.sleep(5000);
                    }catch(InterruptedException e){
                            e.printStackTrace();
                    }
                    System.out.println(getName() + " is running again.");
            }
    }

AppConfig.java

    package com.chszs.config;
    
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    @ComponentScan(basePackages="com.chszs.thread")
    public class AppConfig {
    }

App.java

    package com.chszs;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    
    import com.chszs.config.AppConfig;
    import com.chszs.thread.PrintThread;
    
    public class App {
            public static void main(String[] args){
                    ApplicationContext ctx = 
                new AnnotationConfigApplicationContext(AppConfig.class);
                    PrintThread printThread1 = (PrintThread)ctx.getBean("printThread");
                    printThread1.setName("Thread 1");
    
                    PrintThread printThread2 = (PrintThread)ctx.getBean("printThread");
                    printThread2.setName("Thread 2");
    
                    PrintThread printThread3 = (PrintThread)ctx.getBean("printThread");
                    printThread3.setName("Thread 3");
    
                    PrintThread printThread4 = (PrintThread)ctx.getBean("printThread");
                    printThread4.setName("Thread 4");
    
                    PrintThread printThread5 = (PrintThread)ctx.getBean("printThread");
                    printThread5.setName("Thread 5");
    
                    printThread1.start();
                    printThread2.start();
                    printThread3.start();
                    printThread4.start();
                    printThread5.start();
            }
    }

输出：

Thread 1 is running.

Thread 2 is running.

Thread 4 is running.

Thread 5 is running.

Thread 3 is running.

Thread 2 is running again.

Thread 1 is running again.

Thread 5 is running again.

Thread 4 is running again.

Thread 3 is running again.

例子2：Spring线程池结合非Spring托管Bean。

使用Spring的ThreadPoolTaskExecutor类创建一个线程池。执行线程无需受Spring容器的管理。

PrintTask.java

    package com.chszs.thread;
    
    public class PrintTask implements Runnable{
            String name;
            public PrintTask(String name){
                    this.name = name;
            }
            @Override
            public void run() {
                    System.out.println(name + " is running.");
                    try{
                            Thread.sleep(5000);
                    }catch(InterruptedException e){
                            e.printStackTrace();
                    }
                    System.out.println(name + " is running again.");
            }
    
    }

Spring-Config.xml

    <beans xmlns="http://www.springframework.org/schema/beans"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
            xmlns:context="http://www.springframework.org/schema/context"
            xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context-3.1.xsd">
    
            <bean id="taskExecutor" 
            class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
                    <property name="corePoolSize" value="5" />
                    <property name="maxPoolSize" value="10" />
                    <property name="WaitForTasksToCompleteOnShutdown" value="true" />
            </bean>
    </beans>

注意这个Spring配置文件的位置，如图所示：

App1.java

    package com.chszs;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
    
    import com.chszs.thread.PrintTask;
    
    public class App1 {
    
            public static void main(String[] args) {
                    ApplicationContext ctx = 
                new ClassPathXmlApplicationContext("resources/Spring-Config.xml");
                    ThreadPoolTaskExecutor taskExecutor =
                (ThreadPoolTaskExecutor)ctx.getBean("taskExecutor");
                    taskExecutor.execute(new PrintTask("Thread 1"));
                    taskExecutor.execute(new PrintTask("Thread 2"));
                    taskExecutor.execute(new PrintTask("Thread 3"));
                    taskExecutor.execute(new PrintTask("Thread 4"));
                    taskExecutor.execute(new PrintTask("Thread 5"));
                    // 检查活动的线程，如果活动线程数为0则关闭线程池
                    for(;;){
                            int count = taskExecutor.getActiveCount();
                            System.out.println("Active Threads : " + count);
                            try{
                                    Thread.sleep(1000);
                            }catch(InterruptedException e){
                                    e.printStackTrace();
                            }
                            if(count==0){
                                    taskExecutor.shutdown();
                                    break;
                            }
                    }
            }
    
    }

输出：

Thread 1 is running.

Thread 2 is running.

Thread 3 is running.

Thread 4 is running.

Active Threads : 4

Thread 5 is running.

Active Threads : 5

Thread 4 is running again.

Thread 2 is running again.

Thread 3 is running again.

Thread 1 is running again.

Thread 5 is running again.

Active Threads : 0

作者：chszs，转载需注明。博客主页：http://blog.csdn.net/chszs

例子3：Spring线程池结合Spring托管Bean。

本例仍然使用ThreadPoolTaskExecutor类，并使用@Component注释声明Spring的托管Bean。

下面的例子PrintTask2是Spring的托管Bean，使用@Autowired注释简化代码。

PrintTask2.java

    package com.chszs.thread;
    
    import org.springframework.context.annotation.Scope;
    import org.springframework.stereotype.Component;
    
    @Component
    @Scope("prototype")
    public class PrintTask2 implements Runnable {
            String name;
    
            public void setName(String name) {
                    this.name = name;
            }
    
            @Override
            public void run(){
                    System.out.println(name + " is running.");
                    try{
                            Thread.sleep(5000);
                    }catch(InterruptedException e){
                            e.printStackTrace();
                    }
                    System.out.println(name + " is running again.");
            }
    }

AppConfig.java

    package com.chszs.config;
    
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
    
    @Configuration
    @ComponentScan(basePackages="com.chszs.thread")
    public class AppConfig {
            @Bean
            public ThreadPoolTaskExecutor taskExecutor(){
                    ThreadPoolTaskExecutor pool = new ThreadPoolTaskExecutor();
                    pool.setCorePoolSize(5);
                    pool.setMaxPoolSize(10);
                    pool.setWaitForTasksToCompleteOnShutdown(true);
                    return pool;
            }
    }

App2.java

    package com.chszs;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
    
    import com.chszs.config.AppConfig;
    import com.chszs.thread.PrintTask2;
    
    public class App2 {
            public static void main(String[] args) {
                    ApplicationContext ctx = 
                new AnnotationConfigApplicationContext(AppConfig.class);
                    ThreadPoolTaskExecutor taskExecutor =
                (ThreadPoolTaskExecutor)ctx.getBean("taskExecutor");
    
                    PrintTask2 printTask1 = (PrintTask2)ctx.getBean("printTask2");
                    printTask1.setName("Thread 1");
                    taskExecutor.execute(printTask1);
    
                    PrintTask2 printTask2 = (PrintTask2)ctx.getBean("printTask2");
                    printTask2.setName("Thread 2");
                    taskExecutor.execute(printTask2);
    
                    PrintTask2 printTask3 = (PrintTask2)ctx.getBean("printTask2");
                    printTask3.setName("Thread 3");
                    taskExecutor.execute(printTask3);
    
                    for(;;){
                            int count = taskExecutor.getActiveCount();
                            System.out.println("Active Threads : " + count);
                            try{
                                    Thread.sleep(1000);
                            }catch(InterruptedException e){
                                    e.printStackTrace();
                            }
                            if(count==0){
                                    taskExecutor.shutdown();
                                    break;
                            }
                    }
            }
    
    }