安全多线程例子

package com.ygl;


 public interface Output {

public void output(String str);
}
//**************************
package com.ygl;
 public class Outputer implements Output{
   public void output(String str){
 int len=str.length();
synchronized(this) //或者用方法锁
    {
 for(int i=0;i<len;i++){
System.out.print(str.charAt(i));  
 }
 System.out.println();
 }
   }
 }或者
package com.ygl;


 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;


 public class Outputer implements Output{
Lock lock=new ReentrantLock();
   public void output(String str){
 
 int len=str.length();
   lock.lock();
   try{
    for(int i=0;i<len;i++){
System.out.print(str.charAt(i));  
 }
 System.out.println(); 
   }finally{
    lock.unlock();

 

   }
 }//************************************
package com.ygl;
 public class MyRunnable implements Runnable{
    private  Output obj;
    private String str;
public  MyRunnable ( Output obj,String str){
     this.obj=obj;
     this.str=str;
     }
     public MyRunnable (){
     
     }
@Override
public void run() {
while(true){
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
obj.output(str);
}

}

 }//*********************************
package com.ygl;


 public class TraditionalThreadSynchronized {
    public static void main(String[] args) {
Output output=new Outputer();
Runnable  runnable1 =new MyRunnable(output,"ygl"); 
Runnable  runnable2 =new MyRunnable(output,"liming"); 
Thread thread1=new Thread(runnable1);
thread1.start();
Thread thread2=new Thread(runnable2);
thread2.start();
 }
 }