java多线程---线程之间的通信

1.setDaemon(boolean); 为true 创建后面线程,在调用线程的start()方法之前调用。如果一个进程中没有任何前台线程，就算有后台线程在运行，整个进程仍然会结束。
isDaemon()判断是不是后面进程
Thread tt = new Thread();
tt.isDaemon();  

2.setPriority();   目前windows下只支持三个级别的优先级，分别是:
Thread.MAX_PRIORITY
Thread.MIN_PRIORITY
Thread.NORM_PRIORITY
Thread tt = new Thread();
tt.setPriority(Thread.MAX_PRIORITY);

3.join()
  如果线程A执行时调用了线程B的join方法，那么线程A将会被挂起，待B执行完后再执行A，但join(millisecond)
  有一个millisecond参数，如果过一规定时间线程B没有返回，将强制返回A. 应try{}catch(Exception e){};

// 信息类
class  Q
{
        private String name = "unknown";
        private String sex = "unknown";    
        boolean bFull = false;
        public synchronized void put(String name, String sex)
        {
            if(bFull)
            {
                try{wait();}catch(Exception e){}    
            }
            this.name = name;
            //测试
            try{Thread.sleep(1);}catch(Exception e){}
            this.sex  = sex;    
            bFull = true;
            notify();
        }
        public synchronized void get()
        {
            if(!bFull)
            {
                try{wait();}catch(Exception e){}        
            }
            System.out.print(name);
            System.out.println(":"+sex);    
            bFull = false;
            notify();
        }
        
}

// 生产者类
class  Producer  implements  Runnable
{
    Q q;
    public Producer(Q q)
    {
        this.q = q;    
    }
    public void run()
    {
          int i = 0;
            while(true)
            {
                ///////////////////////////////////////////////////////////////////////
                /**//*synchronized(q)
                {
                    if(q.bFull)
                    {
                        //如果缓冲区还有值，则此线程应该停止并将线程让给读取的线程
                        //必须用同步监时器的对象的wait和notify
                              try{q.wait();}catch(Exception e){}  
                    }
                      
                        if(i == 0)
                        {
                            q.name = "张三";
                            try{Thread.sleep(1);}catch(Exception e){}
                            q.sex  = "男";
                        }
                        else
                        {
                            q.name = "李四";
                            q.sex  = "女";
                        }    
                        q.bFull = true;
                        q.notify();
                    }
                */
                /////////////////////////////////////////
                if( i == 0)
                {
                    q.put("张三","男");    
                }
                else
                {
                    q.put("李四","女");    
                }
                i = (i + 1) % 2;                
            }    
    }
}

// 消费者类
class  Consumer  implements  Runnable
{
    Q q;
    public Consumer(Q q)
    {
        this.q = q;    
    }
    public void run()
    {
        q.get();
        
        ///////////////////////////////////////////////////////
        /**//*synchronized(q)
        {
            while(true)
            {
                    if(!q.bFull)
                    {
                         try{q.wait();}catch(Exception e){}
                    }
                    System.out.println("姓名是:"+q.name );
                    System.out.println("性别是:"+q.sex );
                    q.bFull = false;
                    q.notify();  //唤醒生产者线程
            }        
        
        }            */
        //////////////////////////////////////////////////////////
        
    }
}

// 使用
public   class  lesson51
{
    public static void main(String[] args)
    {
            //Q q = new Q();
            //new Thread(new Producer(q)).start();
            //new Thread(new Consumer(q)).start();
            
            ThreadTest th = new ThreadTest();
            new Thread(th).start();
            for(int i = 0; i < 100; i++)
            {
                if(i == 50)
                {
                        th.stopmyself();
                }    
                System.out.println("main mothed is running " + i + "times");
            }            
    }    
}

class  ThreadTest  implements  Runnable
{
    private boolean bFlag = false;        
    public void run()
    {                
         int i = 0;
            while(!bFlag)
            {
                    System.out.println("Thread name "+Thread.currentThread().getName()+ i++);    
            }    
    }    
    public void stopmyself()
    {
            bFlag = true;    
    }
}