package com.shi.flink.juc;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.LockSupport;
import java.util.concurrent.locks.ReentrantLock;
/**
* @author shiye
* @create 2021-03-17 10:03
*/
public class LocalSupportTest {
public static void main(String[] args) {
lockSupportTest();
}
/**
* LockSupport 测试
*/
private static void lockSupportTest() {
Thread thread1 = new Thread(() -> {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(Thread.currentThread().getName() + " ---->> commint in .. ");
//必须要获得凭证才可以通行
LockSupport.park();
System.out.println("------获得了一个凭证-----");
LockSupport.park();
System.out.println(Thread.currentThread().getName() + " ---->> 被唤醒 .. ");
});
thread1.start();
/**
* 给同一个线程发放多次凭证,只会有一个凭证有效
*/
new Thread(()->{
//给 thread1 发送凭证
LockSupport.unpark(thread1);
System.out.println("------给thread1发送了1个凭证-----");
LockSupport.unpark(thread1);
System.out.println("------给thread1发送了第2个凭证-----");
System.out.println(Thread.currentThread().getName() + " ---->> 通知/唤醒了别得线程 .. ");
}).start();
}
/**
* 1.必须要保证顺序
* 2.必须要加锁
*/
private static void lockTest2() {
Lock lock = new ReentrantLock();
Thread t1 = new Thread(()->{
try {
lock.lock();
System.out.println(Thread.currentThread().getName() + " ---->> commint in .. ");
Thread.currentThread().wait();
System.out.println(Thread.currentThread().getName() + " ---->> 被唤醒 .. ");
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
});
t1.start();
Thread t2 = new Thread(()->{
try {
lock.lock();
t1.notify();
System.out.println(Thread.currentThread().getName() + " ---->> 通知/唤醒了别得线程 .. ");
} finally {
lock.unlock();
}
});
t2.start();
}
/**
* 1.必须要保证顺序
* 2.必须要加锁
*/
private static void synchronizedLock1() {
Object lockObject = new Object();
new Thread(()->{
//如果之前别的线程去提前去唤醒当前线程,则无效
// try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); }
synchronized (lockObject){
System.out.println(Thread.currentThread().getName() + " ---->> commint in .. ");
try {
lockObject.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(Thread.currentThread().getName() + " ---->> 被唤醒 .. ");
}
}).start();
new Thread(()->{
synchronized (lockObject){
lockObject.notify();
System.out.println(Thread.currentThread().getName() + " ---->> 通知/唤醒了别得线程 .. ");
}
}).start();
}
}