线程的实例

package com.apach.jb;

public class threadDemo extends Thread {
int flag;
public threadDemo(String name,int f){
  super(name);
  this.flag=f;
  }
public  void run(){
     char ch;
  System.out.println();
  System.out.print(getName()+" start: ");
  synchronized(this){
  if(flag==0){
  
   for(ch='a';ch<='z';ch++)
    System.out.print(ch+"  ");
  }
 
  else
   if(flag==1){
    for(ch='A';ch<='Z';ch++)
     System.out.print(ch+"  ");
    }
    System.out.print(getName()+" end!");
  }
}

    public static void main (String[] args) {
     threadDemo t1= new threadDemo("线程1",1);
     threadDemo t2= new threadDemo("线程2",0);
     t1.start();
     t2.start();
     System.out.println("active: "+t1.activeCount());
     }
    }
//我想让这个程序按同步机制对象t1,t2分别输出字母的大小写。当t1的进程执行完后，在执行t2的进程。但是不行