java线程中监听值的变化？

Question

socket发送后，接收线程用while(1){get = br.readline(); if(get!=null){recvdata = get;}}在主程序中写入流（发送），怎样在接受线程接到数据时立即再主程序中处理？

Answer 1

就是一个Frame或者一个class里面启动线程，然后要监控线程里的变量变化
public class Frame1 extends JFrame {
        // 建立连接
        try
        {
            connection = new Socket(InetAddress.getLocalHost(),8021);
            JOptionPane.showMessageDialog(this,"连接成功");
        }catch(Exception es)
        {
            JOptionPane.showMessageDialog(this,"错误2"+es.toString());
        }
        // 发送
        try
        {
            // io流
            is = connection.getInputStream();
            os = connection.getOutputStream();
            br = new BufferedReader(new InputStreamReader(is));
            pw = new PrintWriter(os);
            // 线程
            t1 = new Thread(new receiver());
            t1.start();
        } catch (Exception es) {
            JOptionPane.showMessageDialog(this, "错误" + es.toString());
        }
  class receiver implements Runnable
    {
        public receiver()
        {
        }
        public void run()
        {
            
            while(true)
            {
                try
                {
                    changableValue = br.readLine();
                    if(changableValue != null)
                    {
                      recvdata = changableValue ;
                    }
                    else
                    {
                    }
                }catch(Exception ex)
                {
                    //JOptionPane.showMessageDialog(null, "错误1" + ex.toString());
                }
            }
        }    }
}

Answer 2

Swing的话，将其它线程里得到的数据，及处理过程，封装成一个 Runnable 任务，提交给 Swing线程执行
1。SwingUtilities.invokeAndWait(Runnable r)阻塞执行
2。SwingUtilities.invokeLater(Runnable r)异步执行changableValue   =   br.readLine();
if(changableValue==null)
   break;
else{
   final String v = changableValue;
   SwingUtilities.invokeLater(new Runnable(){
      public void run(){
          //将v显示到Swing界面组件上
      }
   });
}                                        if(changableValue   !=   null) 
                                        { 
                                            recvdata   =   changableValue   ; 
                                        } 
                                        else 
                                        { 
                                        } 

Answer 3

上面回复里后面一段代码忘了删，无视之CSDN 怎么不能编辑自己的回帖，真要命