Spring線程池開發實戰

Spring線程池開發實戰

原文出處：點擊打開鏈接

作者：chszs，轉載需註明。

作者博客主頁：http://blog.csdn.net/chszs

本文提供了三個Spring多線程開發的例子，由淺入深，由於例子一目瞭然，所以並未做過多的解釋。諸位一看便知。

前提條件：

1）在Eclipse創建一個Java項目，我取名爲SpringThreadDemo。
2）項目所需的JAR包如圖所示：
 

下面開始。

注：項目源碼已經託管到GitHub，地址：https://github.com/chszs/SpringThreadDemo

例子1：Spring結合Java線程。

通過繼承Thread創建一個簡單的Java線程，然後使用@Component讓spring容器管理此線程，Bean的範圍必須是prototype，因此每個請求都會返回一個新實例，運行每個單獨的線程。

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();
        }
}

輸出：

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線程池結合非Spring託管Bean。

使用Spring的ThreadPoolTaskExecutor類創建一個線程池。執行線程無需受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>

注意這個Spring配置文件的位置，如圖所示：

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"));
                // 檢查活動的線程，如果活動線程數爲0則關閉線程池
                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;
                        }
                }
        }

}

輸出：

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
Active Threads : 5
Active Threads : 5
Active Threads : 5
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，轉載需註明。博客主頁：http://blog.csdn.NET/chszs

例子3：Spring線程池結合Spring託管Bean。

本例仍然使用ThreadPoolTaskExecutor類，並使用@Component註釋聲明Spring的託管Bean。
下面的例子PrintTask2是Spring的託管Bean，使用@Autowired註釋簡化代碼。

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;
                        }
                }
        }

}

輸出：

Thread 1 is running.
Thread 2 is running.
Active Threads : 2
Thread 3 is running.
Active Threads : 3
Active Threads : 3
Active Threads : 3
Active Threads : 3
Thread 1 is running again.
Thread 2 is running again.
Thread 3 is running again.
Active Threads : 1
Active Threads : 0

從這三個簡單的實例中，你是不是發現了Spring框架在多線程方面的強大之處！！