Spring中线程池的用法

多线程并发处理起来通常比较麻烦，如果你使用spring容器来管理业务bean，事情就好办了多了。spring封装了java的多线程的实现，简化了开发。

简单的Hello程序

需要执行的线程类

一般是对于业务的封装.将具体的业务逻辑放到，线程内执行。

public class MessagePrinterTask implements Runnable {    private String message;    public MessagePrinterTask() {    }    public MessagePrinterTask(String message) {        this.message = message;    }    public void run() {        try {            Thread.sleep(3000);            System.out.println(message);        } catch (InterruptedException e) {            e.printStackTrace();        }    }    @Override    public String toString() {        return "MessagePrinterTask [message=" + message + "]";    }}

spring 的配置文件

<?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: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">    <!-- 异步线程池 -->    <bean id="taskExecutor"        class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">        <!-- 核心线程数 -->        <property name="corePoolSize" value="10" />        <!-- 最大线程数 -->        <property name="maxPoolSize" value="50" />        <!-- 队列最大长度 >=mainExecutor.maxSize -->        <property name="queueCapacity" value="100" />        <!-- 线程池维护线程所允许的空闲时间 -->        <property name="keepAliveSeconds" value="300" />        <!-- 线程池对拒绝任务(无线程可用)的处理 策略 -->        <!-- 若不作该处理，当线程满了，队列满了之后，继续往下增加任务，则抛出异常，拒绝该任务 -->        <!-- <property name="rejectedExecutionHandler"> <bean class="java.util.concurrent.ThreadPoolExecutor$CallerRunsPolicy" /> </property> -->    </bean>    <!-- 处理业务的线程 -->    <bean id="messagePrinterTask" class="com.test.sping.thread.MessagePrinterTask" /></beans>

测试代码

• 测试代码

import java.util.concurrent.Executor;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class ThreadTest {    public static void main(String[] args) {        ApplicationContext appContext = new ClassPathXmlApplicationContext("applicationContext.xml");        Executor executor = (Executor) appContext.getBean("taskExecutor");        for (int i = 0; i < 10; i++) {            MessagePrinterTask mTask = new MessagePrinterTask("Message data  is " + i);            executor.execute(mTask);        }        System.out.println("I am from Main Thread ...");    }}

• 测试代码的运行结果

I am from Main Thread ...Message data  is 5Message data  is 7Message data  is 6Message data  is 8Message data  is 4Message data  is 9Message data  is 0Message data  is 3Message data  is 1Message data  is 2

在Spring容器启动的时候,启动一个线程

spring的配置文件

<?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: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">    <!-- 执行业务方法的线程 -->    <bean id="scheduledThread" class="com.test.sping.thread.ScheduledThread" />    <!-- 这样设置容器一启动就自动运行某个线程 start -->    <bean id="springScheduleExecutorTask" class="org.springframework.scheduling.concurrent.ScheduledExecutorTask">        <!-- messagePrinterTask为线程类 -->        <property name="runnable" ref="scheduledThread" />        <!-- 容器加载5秒后开始执行 -->        <property name="delay" value="5000" />        <!-- 每次任务间隔 2秒，循环执行该线程，删除该设定就容器启动后只执行一次 -->        <property name="period" value="2000" />    </bean>   <!-- 这样设置容器一启动就自动运行某个线程  -->    <bean id="springScheduledExecutorFactoryBean" class="org.springframework.scheduling.concurrent.ScheduledExecutorFactoryBean">        <property name="scheduledExecutorTasks">            <list>                <ref bean="springScheduleExecutorTask" />            </list>        </property>    </bean></beans>

业务线程

public class ScheduledThread implements Runnable {    @Override    public void run() {        while (true) {            try {                Thread.sleep(5000);                System.out.println(" I am from ScheduledThread ...");            } catch (InterruptedException e) {                e.printStackTrace();            }        }    }}

测试代码

import org.springframework.context.support.ClassPathXmlApplicationContext;public class ScheduledThreadTest {    public static void main(String[] args) {        ClassPathXmlApplicationContext appContext = new ClassPathXmlApplicationContext("applicationContext-scheduled.xml");        try {            Thread.sleep(Integer.MAX_VALUE);        } catch (InterruptedException e) {            e.printStackTrace();        }    }}