Guarded Suspension 模式
Guarded Suspension 模式通过让线程等待保证线程的安全性。
实际案例
类信息概览：
| 类名 | 说明 |
|---|---|
| Main.java | 方法的总入口 |
| ClientThread.java | 发送请求的类 |
| ServerThread.java | 接受请求的类 |
| RequestQueue.java | 依次存放请求的类 |
| Request.java | 标识一个请求的类 |
定义
- ClientThread.java
package com.github.houbb.thread.learn.easy.learn.guarded.suspension;
import java.util.Random;
public class ClientThread extends Thread {
private final Random random;
private final RequestQueue requestQueue;
public ClientThread(RequestQueue requestQueue, final String name, final long seed) {
super(name);
this.requestQueue = requestQueue;
random = new Random(seed);
}
@Override
public void run() {
for(int i = 0; i < 10; i++) {
Request request = new Request("No. " + i);
requestQueue.putRequest(request);
System.out.println(Thread.currentThread().getName() + " put " + request);
try {
Thread.sleep(random.nextInt(1000));
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
- ServerThread.java
package com.github.houbb.thread.learn.easy.learn.guarded.suspension;
import java.util.Random;
public class ServerThread extends Thread {
private final Random random;
private final RequestQueue requestQueue;
public ServerThread(RequestQueue requestQueue, final String name, final long seed) {
super(name);
this.requestQueue = requestQueue;
random = new Random(seed);
}
@Override
public void run() {
for(int i = 0; i < 10; i++) {
Request request = requestQueue.getRequest();
System.out.println(Thread.currentThread().getName()+" get "+request);
try {
Thread.sleep(random.nextInt(1000));
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
- RequestQueue.java
package com.github.houbb.thread.learn.easy.learn.guarded.suspension;
import java.util.LinkedList;
import java.util.Queue;
public class RequestQueue {
private Queue<Request> requestQueue = new LinkedList<>();
/**
* 获取一个对象
* 1. 如果队列为空，则一直等待。
* @return
*/
public synchronized Request getRequest() {
while(requestQueue.peek() == null) {
try {
wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
// Retrieves and removes the head of this queue.
return requestQueue.remove();
}
/**
* 放置一个对象
* @param request
*/
public synchronized void putRequest(Request request) {
requestQueue.add(request);
notifyAll();
}
}
- Request.java
package com.github.houbb.thread.learn.easy.learn.guarded.suspension;
/**
* 请求参数
* @version 1.0.0
* @author bbhou
* @since 1.0.0
*/
public class Request {
private final String name;
public Request(String name) {
this.name = name;
}
public String getName() {
return name;
}
@Override
public String toString() {
return "Request{" +
"name='" + name + '\'' +
'}';
}
}
测试
- Main.java
package com.github.houbb.thread.learn.easy.learn.guarded.suspension;
public class Main {
public static void main(String[] args) {
RequestQueue requestQueue = new RequestQueue();
new ClientThread(requestQueue, "CLIENT", 10000L).start();
new ServerThread(requestQueue, "SERVER", 20000L).start();
}
}
- 测试结果
CLIENT put Request{name='No. 0'}
SERVER get Request{name='No. 0'}
CLIENT put Request{name='No. 1'}
SERVER get Request{name='No. 1'}
CLIENT put Request{name='No. 2'}
CLIENT put Request{name='No. 3'}
SERVER get Request{name='No. 2'}
SERVER get Request{name='No. 3'}
CLIENT put Request{name='No. 4'}
CLIENT put Request{name='No. 5'}
SERVER get Request{name='No. 4'}
CLIENT put Request{name='No. 6'}
CLIENT put Request{name='No. 7'}
SERVER get Request{name='No. 5'}
CLIENT put Request{name='No. 8'}
SERVER get Request{name='No. 6'}
CLIENT put Request{name='No. 9'}
SERVER get Request{name='No. 7'}
SERVER get Request{name='No. 8'}
SERVER get Request{name='No. 9'}
实现方式
UML & Code
UML
UML 图示如下
Code
代码地址
