java 实现死锁

Posted 2022-01-20 六道对穿肠

资源抢占 导致死锁

public static void main(String[] args) 
        final Object a = new Object();
        final Object b = new Object();
        Thread threadA = new Thread(new Runnable() 
            public void run() 
                synchronized (a) 
                    try 
                        System.out.println("now i in threadA-locka");
                        Thread.sleep(1000l);
                        synchronized (b) 
                            System.out.println("now i in threadA-lockb");
                        
                     catch (Exception e) 
                        // ignore
                    
                
            
        );

        Thread threadB = new Thread(new Runnable() 
            public void run() 
                synchronized (b) 
                    try 
                        System.out.println("now i in threadB-lockb");
                        Thread.sleep(1000l);
                        synchronized (a) 
                            System.out.println("now i in threadB-locka");
                        
                     catch (Exception e) 
                        // ignore
                    
                
            
        );

        threadA.start();
        threadB.start();
    

第二种写法 思路都一样

public static void miin(String[] args)
    
    final Object lockA = new Object();
    final Object lockB = new Object();
    
    Thread threadA = new Thread(new Runable
        public void run()
            synchnaized(lockA)
                Sleep(1000);
                synchnaized(LockB)
                    
                
            
        
    );
    
    Thread threadB = new Thread(new Runable
        public void run()
            synchnaized(lockB)
                Sleep(1000);
                synchnaized(LockA)
                    
                
            
        
    );
    
    threadA.start();
    threadB.start();