java 多线程（ReadWriteLock）

package com.example;

public class App {

public static void main(String[] args) {
Info info = new Info();
ReadInfo ri = new ReadInfo(info);
WriteInfo wi = new WriteInfo(info);

Thread t1 = new Thread(ri,"ri1");
Thread t2 = new Thread(ri,"ri2");
Thread t3 = new Thread(ri,"ri3");
Thread t4 = new Thread(wi,"wi1");
Thread t5 = new Thread(wi,"wi2");

t1.start();
t2.start();
t3.start();
t4.start();
t5.start();
}
}

package com.example;

import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

public class Info {
private int num;
//ReadWriteLock 可以理解为对synchronized更加精细化的管理
private ReadWriteLock lock;

public Info(){
this.num = 0;
lock = new ReentrantReadWriteLock();
}

public int getNum(){
lock.writeLock().lock();
int output = this.num;
lock.writeLock().unlock();
return output;
}

public void setNum(int input){
lock.readLock().lock();
this.num = input;
lock.readLock().unlock();
}
}

package com.example;

public class ReadInfo implements Runnable {

private Info info;

public ReadInfo(Info in){
this.info = in;
}

@Override
public void run() {
for(int i = 0; i < 10; i++){
System.out.println(Thread.currentThread().getName() + "   " + info.getNum());
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}

package com.example;

public class WriteInfo implements Runnable {

private Info info;

public WriteInfo(Info in){
this.info = in;
}

@Override
public void run() {
for(int i = 0; i < 10; i++){
info.setNum(i + info.getNum());
System.out.println(Thread.currentThread().getName() + "  setInfo:  " + info.getNum());
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}