更改布爾變量的JTextPane文本

Question

我有一個主類有兩個子類，一個用於GUI初始化，另一個用於服務器創建和功能。我有一個布爾變量「連接」，當用戶連接到服務器時爲true，否則爲false。我如何能夠在服務器子類中更新GUI子類中的JTextPane文本，以在「連接」爲真時稱「客戶端連接」，在錯誤時稱爲「無連接」？

主類：

public class serverMain { 

    public static boolean allowConnections = false; 
    public static boolean connected = false; 
    public static boolean launchOnStart = false; 
    public static boolean loop = true; 

    public static int serverPort = 1234; 
    public static ServerSocket serverSocket; 

    public static void main(String args[]){ 

     serverGUI.gui(); 

     while (loop){ 

      if (allowConnections == true){ 
       serverCommands.commands(); 
      } 
      else { 
       System.out.println("reject"); 
      } 

     } 

    } 

} 

GUI類（去除不相關部分）：

public class serverGUI extends serverMain { 

    public static JTextPane txtConnectionMarker; 

    public static void gui(){ 
     EventQueue.invokeLater(new Runnable() { 
      public void run() { 
       try { 
        serverGUI window = new serverGUI(); 
        window.frmRemoteServer.setVisible(true); 
       } 
       catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 
    } 

    public serverGUI() { 
     initialise(); 
    } 

    public void initialise() { 

     frmRemoteServer = new JFrame(); 
     frmRemoteServer.setBounds(100, 100, 720, 420); 
     frmRemoteServer.setResizable(false); 
     frmRemoteServer.setTitle("Remote Server"); 
     frmRemoteServer.getContentPane().setBackground(Color.WHITE); 
     frmRemoteServer.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frmRemoteServer.getContentPane().setLayout(null); 

     JTextPane txtConnectionMarker = new JTextPane(); 
     txtConnectionMarker.setEditable(false); 
     txtConnectionMarker.setBounds(548, 21, 149, 33); 
     txtConnectionMarker.setFont(new Font("Segoe UI Light", Font.BOLD, 16)); 
     txtConnectionMarker.setBackground(SystemColor.menu); 
     frmRemoteServer.getContentPane().add(txtConnectionMarker); 

     if (connected == true){ 
      txtConnectionMarker.setText("Connected"); 
      txtConnectionMarker.setForeground(Color.GREEN); 
     } 
     else { 
      txtConnectionMarker.setText("No Connection"); 
      txtConnectionMarker.setForeground(Color.RED); 
     } 

     // obviously this will not update as connected changes 

    } 
} 

服務器類（不相關的部分去掉）：

public class serverCommands extends serverMain { 

    public static void commands() { 

     String input; 

     try { 

      serverSocket = new ServerSocket(serverPort); 
      System.out.println("socket opened on port "+serverPort); 

      Socket clientSocket = serverSocket.accept(); 
      connected = true; 

      // there's more to all parts but the given code 
      // should be enough to get what I'm trying to do 
      // basically once the user disconnects connected 
      // will change back to false 

Answer 1

您可以創建一個排序監聽器使用一個java接口，監聽器方法的實現被寫入你的子類中。

public interface ResultListener { 
    public void setResult(boolean result); 
} 

然後你唯一需要的就是將這個接口作爲參數傳遞給初始化服務器並調用監聽器方法的參數。

public class MyServer { 

    private ResultListener listener; 

    public MyServer(ResultListener listener) { 
     this.listener = listener; 
    } 

    public void doSomething() { 

     // other stuff 
     listener.setResult(true); // or false if connected or not 

    } 

} 

最後：

public class MainClass implements ResultListener { 

    public void init() { 
     // your GUI and other logic 

     MyServer server = new MyServer(this); 
     server.doSomething(); 

    } 

    @Override 
    public void setResult(boolean result) { 

     if(result) { 
      // do stuff 
      label.setText("Connected!"); 
     } else { 
      // do other stuff 
      label.setText("Connection failed!"); 
     } 
    } 

}