Multithreading Diary (17.5.2two) basic rules for synchronized

Synchronized keywords

1) When a thread accesses an object's synchronized method or block of code, access to other threads will be blocked;

2) When a thread accesses an object's synchronized method or block of code, the other thread accesses the object's non-synchronized code block without blocking it;

3) When a thread accesses a synchronized method or block of code for an object, other threads will be blocked when they access other synchronized code blocks of that object.

First Rule

 Public classTest { Public Static voidMain (String[]args) {//Create object for the threadsNewthread obj=NewNewthread (); //Create new ThreadThread thread1=NewThread (obj, "T1"); Thread thread2=NewThread (obj, "T2");        Thread1.start ();    Thread2.start (); }}classNewthreadImplementsrunnable{@Override Public voidrun () {synchronized( This){            Try{                 for(inti=0;i<3;i++) {Thread.Sleep (100); System.out.println (Thread.CurrentThread (). GetName ()+ ":" + (i+1)); }            }Catch(interruptedexception e) {System.out.println ("Error"); }        }    }    }

Rule number two:

 Public classTest { Public Static voidMain (String[]args) {FinalDemo demo=NewDemo (); //Create first threadThread thread1=NewThread (NewRunnable () {@Override Public voidrun () {demo.synchronizedthread (); }        },"T1"); //Create second threadThread thread2=NewThread (NewRunnable () {@Override Public voidrun () {demo.unsynchronizedthread (); }        },"T2");        Thread1.start ();    Thread2.start (); }}classdemo{//Synchronized Method     Public voidSynchronizedthread () {synchronized( This){            Try{                 for(inti=0;i<3;i++) {System.out.println (Thread.CurrentThread (). GetName ()+ ":" + (i+1)); Thread.Sleep (100); }            }Catch(interruptedexception e) {System.out.println ("Error"); }        }    }    //unsynchronized Method     Public voidUnsynchronizedthread () {Try{             for(inti=0;i<3;i++) {System.out.println (Thread.CurrentThread (). GetName ()+ ":" + (i+1)); Thread.Sleep (100); }        }Catch(interruptedexception e) {System.out.println ("Error"); }    }}

Rule three:

 Public classTest { Public Static voidMain (String[]args) {FinalDemo demo=NewDemo (); //Create first threadThread thread1=NewThread (NewRunnable () {@Override Public voidrun () {demo.synchronizedthread (); }        },"T1"); //Create second threadThread thread2=NewThread (NewRunnable () {@Override Public voidrun () {demo.samesynchronizedthread (); }        },"T2");        Thread1.start ();    Thread2.start (); }}classdemo{//Synchronized Method     Public voidSynchronizedthread () {synchronized( This){            Try{                 for(inti=0;i<3;i++) {System.out.println (Thread.CurrentThread (). GetName ()+ ":" + (i+1)); //sleep (+)Thread.Sleep (100); }            }Catch(interruptedexception e) {System.out.println ("Error"); }        }    }    //Synchronized Method     Public voidSamesynchronizedthread () {synchronized( This){            Try{                 for(inti=0;i<3;i++) {System.out.println (Thread.CurrentThread (). GetName ()+ ":" + (i+1)); //sleep (+)Thread.Sleep (100); }            }Catch(interruptedexception e) {System.out.println ("Error"); }        }    }}

Synchronized methods and blocks of code

Method: Public synchronized void Method1 () {}

Code block: Class Lei{synchronized (This)}

Reference from: HTTP://WWW.CNBLOGS.COM/SKYWANG12345/P/3479202.HTML#P3

Multithreading Diary (17.5.2two) basic rules for synchronized