文章目录

Java多线程相关知识【15】--设计模式--确保挂起模式（Guarded Suspension）1.问题的引入2.问题的解决3.实现的代码请求队列请求体连接端服务端使用方法 菜鸟的一个学习笔记，欢迎大神 批评指正。

Java多线程相关知识【15】–设计模式–确保挂起模式（Guarded Suspension）

1.问题的引入

​ 一个线程正在做一个非常关键的任务，这时，有一个其他的线程让当前线程做其他的事情，当前线程只有完成当前的任务才能做其他的任务。

2.问题的解决

​ 使用队列将其他需要工作的线程保存，然后在未来需要时，继续取队列中获取任务，然后执行。

3.实现的代码

请求队列

package com.company.ThreadCharPart2.guardedsuspension; import java.util.LinkedList; /** * 请求队列 */ public class GuardedSuspensionQueue { /** * 队列 */ LinkedList<GuardedSuspension> queue = new LinkedList<>(); /** * 获取队列的元素 * * @return */ public GuardedSuspension getGuardedSuspension() { synchronized (queue) { while (queue.size() <= 0) { try { queue.wait(); } catch (InterruptedException e) { return null; } } return queue.removeFirst(); } } /** * 向队列中添加元素 * * @param guardedSuspension 要添加的元素 */ public void putGuardedSuspension(GuardedSuspension guardedSuspension) { synchronized (queue) { queue.addLast(guardedSuspension); queue.notifyAll(); } } }

请求体

/** * 请求元素体 */ public class GuardedSuspension<T> { /** * 请求元素的类型 */ final private T value; public GuardedSuspension(T value) { this.value = value; } /** * 获取元素 * * @return */ public T getValue() { return value; } }

连接端

/** * 客户端操作 * @param <T> */ public class GuardedSuspensionClientThread<T> extends Thread { private final GuardedSuspensionQueue queue; private final T value; private final Random random; public GuardedSuspensionClientThread(GuardedSuspensionQueue queue, T value) { this.queue = queue; this.value = value; this.random = new Random(System.currentTimeMillis()); } @Override public void run() { for (int i = 0; i < 10; i++) { System.out.println("This client value ->"+value); queue.putGuardedSuspension(new GuardedSuspension(value)); try { Thread.sleep(random.nextInt(1000)); } catch (InterruptedException e) { e.printStackTrace(); } } } }

服务端

/** * 服务端 */ public class GuardedSuspensionServerThread extends Thread { private final GuardedSuspensionQueue queue; private final Random random; //标识是否确认关闭 private volatile boolean close = false; public GuardedSuspensionServerThread(GuardedSuspensionQueue queue) { this.queue = queue; random = new Random(System.currentTimeMillis()); } @Override public void run() { while (!close) { GuardedSuspension suspension = queue.getGuardedSuspension(); if (suspension == null) { System.out.println("error"); continue; } System.out.println("Server ->" + suspension.getValue()); try { Thread.sleep(random.nextInt(1000)); } catch (InterruptedException e) { return; } } } /** * 关闭服务端 */ public void close() { this.close = true; this.interrupt(); } }

使用方法

/** * 测试连接 */ public class GuardedSuspensionClient { public static void main(String[] args) throws InterruptedException { //初始化队列 final GuardedSuspensionQueue queue = new GuardedSuspensionQueue(); //客户端初始化并启动 new GuardedSuspensionClientThread(queue, "test").start(); //服务端操作 GuardedSuspensionServerThread guardedSuspensionServerThread = new GuardedSuspensionServerThread(queue); guardedSuspensionServerThread.start(); Thread.sleep(11000L); guardedSuspensionServerThread.close(); } }