Multithreading (understanding of 1_ lock _2_ deadlock analysis)

We created 4 threads, which, unlike before, used synchronous functions and synchronized code quickly. See how it turns out.

classMlpcImplementsrunnable{Private intTicket = 550;  Public BooleanFlag =true; Object obj=NewObject ();  Public voidrun () {if(Flag = =true)        {             while(true)            {                synchronized (obj) {if(ticket>0)                    {                        if(ticket>0)                        {                                Try{Thread.Sleep (20); }                            Catch(Exception e) {} System.out.println (Thread.CurrentThread ()+ "Show" +ticket--); }                     }                }            }        }        Else        {             while(true) {show (); }        }    }    Public   synchronized void  Show () {if(ticket>0)            {                    Try{Thread.Sleep (20); }                Catch(Exception e) {} System.out.println (Thread.CurrentThread ()+ "Show" +ticket--); }                     }} classMlpcdemo { Public Static voidMain (string[] args) {MLPC m=NewMLPC (); Thread Th0=NewThread (m); Thread Th1=NewThread (m); Thread Th2=NewThread (m); Thread Th3=NewThread (m);        Th0.start (); Try{Thread.Sleep (20); }        Catch(Exception e) {} M.flag=false;        Th1.start ();        Th2.start ();    Th3.start (); }}

The result was a vote of 0.

  Public voidrun () {if(Flag = =true)        {             while(true)            {                synchronized (  This)//change from the original arbitrary object to a functionthe object to which you belongThis  
               {                    if(ticket>0)                    {                            Try{Thread.Sleep (20); }                        Catch(Exception e) {} System.out.println (Thread.curr Entthread ()+ "Show" +ticket--); }                 }            }        }        Else        {             while(true) {show (); }        }    }

Multithreading (understanding of 1_ lock _2_ deadlock analysis)