设计模式-单线程执行模式

单线程执行模式

场景：有一个门，记录每次进入们的用户的姓名和来历

package com.ln.concurrent.chapter5;
/**
 * @ProjectName: java-concurrency
 * @Package: com.ln.concurrent.chapter5
 * @version: 1.0
 */

/**
 * @ClassName:Gate
 * @Author:linianest
 * @CreateTime:2020/3/24 9:06
 * @version:1.0
 * @Description TODO: 定义共享资源
 */

/**
 * SharedResource
 */
public class Gate {
     
    private int counter = 0;
    private String name = "NoBody";
    private String address = "NoWhere";

    /**
     * 临界值
     * @param name
     * @param address
     */
    public synchronized void pass(String name, String address) {
     
        this.counter++;
        this.name = name;
        this.address = address;
        verify();
    }

    private void verify() {
     
        if (this.name.charAt(0) != this.address.charAt(0)) {
     
            System.out.println("************BROKEN**************" + toString());
        }
    }

    @Override
    public String toString() {
     
        return "NO." + counter + ":" + name + "," + address;
    }
}

package com.ln.concurrent.chapter5;
/**
 * @ProjectName: java-concurrency
 * @Package: com.ln.concurrent.chapter5
 * @version: 1.0
 */

/**
 * @ClassName:User
 * @Author:linianest
 * @CreateTime:2020/3/24 9:11
 * @version:1.0
 * @Description TODO: 定义调用资源的线程
 */
public class User extends Thread {
     

    private final String myName;
    private final String myAdress;
    private final Gate gate;
    private static volatile int number;

    public User(String myName, String myAdress, Gate gate) {
     
        this.myName = myName;
        this.myAdress = myAdress;
        this.gate = gate;
    }


    @Override
    public void run() {
     
        System.out.println(myName + " BEGIN");
        while (true) {
     
            this.gate.pass(myName, myAdress);
            try {
     
                Thread.sleep(1_000L);
                System.out.println("the thread " + Thread.currentThread().getName() + " coming ,the number is " + (number++));
            } catch (InterruptedException e) {
     
                e.printStackTrace();
            }
        }
    }
}

package com.ln.concurrent.chapter5;
/**
 * @ProjectName: java-concurrency
 * @Package: com.ln.concurrent.chapter5
 * @version: 1.0
 */

/**
 *@ClassName:Client
 *@Author:linianest
 *@CreateTime:2020/3/24 9:17
 *@version:1.0
 *@Description TODO: 实现一个资源每次只有一个线程访问
 */
public class Client {
     
    public static void main(String[] args) {
     
        Gate gate = new Gate();
        User bj = new User("Baobao","Beijin",gate);
        User sh = new User("ShangLao","ShangHai",gate);
        User gz = new User("GuangLao","GuangZhou",gate);

        bj.start();
        sh.start();
        gz.start();
    }
}

通过加锁的方式实现资源每次只能被一个线程访问