ReentrantLock替换synchronized解决多线程并发死锁，Java

比眉伴天荒 2023-09-24 13:49 67阅读 0赞

## ReentrantLock替换synchronized解决多线程并发死锁，Java ##

##  ##

import java.util.concurrent.locks.ReentrantLock;
    
    public class MainClass {
        private ReentrantLock lock1 = new ReentrantLock();
    
        private ReentrantLock lock2 = new ReentrantLock();
    
    
        public static void main(String[] args) {
            MainClass mainClass = new MainClass();
            mainClass.demo();
        }
    
        private void demo() {
            Thread ta = new Thread(new DeadA());
            Thread tb = new Thread(new DeadB());
            ta.start();
            tb.start();
        }
    
        private class DeadA implements Runnable {
            private String id = "A";
    
            @Override
            public void run() {
                System.out.println(id + " 申请锁1...");
                lock1.lock();
                System.out.println(id + " 获得锁1");
                lock1.unlock();
    
                System.out.println(id + " 申请锁2...");
                lock2.lock();
                System.out.println(id + " 获得锁2");
                lock2.unlock();
    
                System.out.println(id + " 运行结束");
            }
        }
    
        private class DeadB implements Runnable {
            private String id = "B";
    
            @Override
            public void run() {
                System.out.println(id + " 申请锁2...");
                lock2.lock();
                System.out.println(id + " 获得锁2");
                lock2.unlock();
    
                System.out.println(id + " 申请锁1...");
                lock1.lock();
                System.out.println(id + " 获得锁1");
                lock1.unlock();
    
                System.out.println(id + " 运行结束");
            }
        }
    }

输出：

> A 申请锁1...  
> B 申请锁2...  
> B 获得锁2  
> A 获得锁1  
> B 申请锁1...  
> B 获得锁1  
> A 申请锁2...  
> B 运行结束  
> A 获得锁2  
> A 运行结束

[Java多线程并发环境下的synchronized死锁实例\_zhangphil的博客-CSDN博客Java并发多线程环境中，造成死锁的最简单的场景是：多线程中的一个线程T\_A持有锁L1并且申请试图获得锁L2，而多线程中另外一个线程T\_B持有锁L2并且试图申请获得锁L1。线程的锁申请操作是阻塞的，于是造成线程T\_A和线程T\_B无法正确获得想要的锁，两个线程被阻塞进入死锁状态。![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/127534524][Java_synchronized_zhangphil_-CSDN_Java_T_A_L1_L2_T_B_L2_L1_T_A_T_B_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_127534524]

[Java线程同步可重入锁ReentrantLock与Condition\_zhangphil的博客-CSDN博客import java.util.LinkedList;import java.util.Queue;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.ReentrantLock;public class Main \{ private Queue<Integer>...![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/92814997][Java_ReentrantLock_Condition_zhangphil_-CSDN_import java.util.LinkedList_import java.util.Queue_import java.util.concurrent.locks.Condition_import java.util.concurrent.locks.ReentrantLock_public class Main _ private Queue_Integer_..._favicon32.ico_https_blog.csdn.net_zhangphil_article_details_92814997]

[Java线程同步锁ReentrantLock和Condition中断等待程序前提条件满足\_zhangphil的博客-CSDN博客import java.util.concurrent.TimeUnit;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.ReentrantLock;/\*\* \* ReentrantLock的lock和unlock必须成对使用且把需要同步的代码块包裹起来。 \* lock-unlo...![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/92826986][Java_ReentrantLock_Condition_zhangphil_-CSDN_import java.util.concurrent.TimeUnit_import java.util.concurrent.locks.Condition_import java.util.concurrent.locks.ReentrantLock_ _ ReentrantLock_lock_unlock_ _ lock-unlo..._favicon32.ico_https_blog.csdn.net_zhangphil_article_details_92826986]

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[Java_ReentrantLock_Condition_zhangphil_-CSDN_import java.util.LinkedList_import java.util.Queue_import java.util.concurrent.locks.Condition_import java.util.concurrent.locks.ReentrantLock_public class Main _ private Queue_Integer_..._favicon32.ico_https_blog.csdn.net_zhangphil_article_details_92814997]: https://blog.csdn.net/zhangphil/article/details/92814997
[Java_ReentrantLock_Condition_zhangphil_-CSDN_import java.util.concurrent.TimeUnit_import java.util.concurrent.locks.Condition_import java.util.concurrent.locks.ReentrantLock_ _ ReentrantLock_lock_unlock_ _ lock-unlo..._favicon32.ico_https_blog.csdn.net_zhangphil_article_details_92826986]: https://blog.csdn.net/zhangphil/article/details/92826986