EDT和更新狀態文本區域

我想創建新線程（用於服務器）。我有textArea放置我的日誌，我創建了一個新的類狀態來處理它。我運行新的線程對象「服務器」，我嘗試「傳遞」我的狀態對象到服務器，並在那裏做status.setStatus（「blabal」）;但是有一個問題....EDT和更新狀態文本區域

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException 
at Server.<init>(Server.java:16) 
at Main.MainPanelButtonStartActionPerformed(Main.java:154) 
at Main.access$000(Main.java:9) 
at Main$1.actionPerformed(Main.java:63) 
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018) 
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341) 
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402) 
at javax.swing.JToggleButton$ToggleButtonModel.setPressed(JToggleButton.java:308) 
at 

javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252) 
    at java.awt.Component.processMouseEvent(Component.java:6505) 
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3321) 
    at java.awt.Component.processEvent(Component.java:6270) 
    at java.awt.Container.processEvent(Container.java:2229) 
    at java.awt.Component.dispatchEventImpl(Component.java:4861) 
    at java.awt.Container.dispatchEventImpl(Container.java:2287) 
    at java.awt.Component.dispatchEvent(Component.java:4687) 
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832) 
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492) 
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422) 
    at java.awt.Container.dispatchEventImpl(Container.java:2273) 
    at java.awt.Window.dispatchEventImpl(Window.java:2719) 
    at java.awt.Component.dispatchEvent(Component.java:4687) 
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:723) 
    at java.awt.EventQueue.access$200(EventQueue.java:103) 
    at java.awt.EventQueue$3.run(EventQueue.java:682) 
    at java.awt.EventQueue$3.run(EventQueue.java:680) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at    java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) 
    at java.awt.EventQueue$4.run(EventQueue.java:696) 
    at java.awt.EventQueue$4.run(EventQueue.java:694) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) 
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:693) 
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) 
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) 
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) 
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) 
Exception in thread "Thread-2" java.lang.NullPointerException 
    at Server.run(Server.java:23) 
    at java.lang.Thread.run(Thread.java:722) 
BUILD SUCCESSFUL (total time: 3 seconds)

我的代碼：私人無效MainPanelButtonStartActionPerformed（EVT java.awt.event.ActionEvent中）{

if(!serverCreated) {   
     server = new Server(Integer.parseInt(MainPanelTextPort.getText())); 
     server.setStatusObj(status); 
     serverThread = new Thread(server);   
     //SwingUtilities.invokeLater(serverThread); don't know how to use it correctly 
     serverThread.start();    
     MainPanelButtonStart.setText("Stop"); 
     serverCreated = true; 
    } else { 
     if(!(serverThread.isInterrupted())) 
     { 
      try { 
       server.getServerSocket().close(); 
      } catch(IOException e) {} 

      serverThread.interrupt(); 
      MainPanelButtonStart.setText("Start"); 
      serverCreated = false; 
     } 
    } 
}

來源

2013-01-18 Sheppard25

異常表明您的'Server（int）'構造函數中存在問題。向我們展示那段代碼。 – predi

http://wklej.org/id/929231/ – Sheppard25

變量status不上這條線實例在Server構造：

status.setStatus("Server Created.");

假設這表示RUNNING，STOPPED等等，這些可以在Server類的內部設置，因爲它可以確定服務器本身的運行狀態。

定期Threads不封裝與Event Dispatch Thread正確的相互作用。 SwingWorker在這裏會是更好的選擇。這post有一個例子。

旁白：鑑於Java code conventions，MainPanelTextPort將表示爲mainPanelTextPort。

來源

2013-01-18 13:01:16 Reimeus

組件MainPanelTextPort被初始化。如何將這個SwingWorker與我的代碼一起使用？ – Sheppard25

你可以發佈一個[SSCCE]（http://sscce.org/）用於類「服務器」，並指出錯誤發生的第16行嗎？ – Reimeus

http://wklej.org/id/929231/ - 我想現在你會明白我的問題是 – Sheppard25

EDT和更新狀態文本區域

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