Odd Java FXML NumberFormatException? 내가 작업을 할 때마다

Question

, 나는이

Button[id=gButton, styleClass=button]'Guess' 
gField content: 44 
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException 
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1762) 
    at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1645) 
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) 
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49) 
    at javafx.event.Event.fireEvent(Event.java:198) 
    at javafx.scene.Node.fireEvent(Node.java:8216) 
    at javafx.scene.control.Button.fire(Button.java:185) 
    at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182) 
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96) 
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:89) 
    at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218) 
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) 
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54) 
    at javafx.event.Event.fireEvent(Event.java:198) 
    at javafx.scene.Scene$MouseHandler.process(Scene.java:3724) 
    at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3452) 
    at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1728) 
    at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2461) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:348) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:273) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:382) 
    at com.sun.glass.ui.View.handleMouseEvent(View.java:553) 
    at com.sun.glass.ui.View.notifyMouse(View.java:925) 
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method) 
    at com.sun.glass.ui.win.WinApplication.lambda$null$141(WinApplication.java:102) 
    at com.sun.glass.ui.win.WinApplication$$Lambda$37/728890494.run(Unknown Source) 
    at java.lang.Thread.run(Thread.java:745) 
Caused by: java.lang.reflect.InvocationTargetException 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:483) 
    at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71) 
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:483) 
    at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275) 
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1757) 
    ... 47 more 
Caused by: java.lang.NumberFormatException: For input string: "" 
    at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65) 
    at java.lang.Integer.parseInt(Integer.java:592) 
    at java.lang.Integer.parseInt(Integer.java:615) 
    at javafxapplication.FXMLDocumentController.handleButtonAction(FXMLDocumentController.java:44) 
    ... 57 more 

주의를 얻을 NumberFormatException for input string: ""은 - 당신이 gField content: 44 은 여기, 2 호선 내 입력을 볼 수 있습니다 내 FXMLDocumentController.java :

:

private Label gLabel; 
@FXML 
private Button rButton; 
@FXML 
private Button gButton; 
@FXML 
private SubScene colorBar; 
@FXML 
private TextField gField; 

@FXML 
private void handleButtonAction(ActionEvent event) { 
    Object source = event.getSource(); 
    String guess = gField.getText(); 
    System.out.println("You clicked me!"); 
    System.out.println(source); 
    if (source == gButton || source == gButton) { 
     if (Integer.parseInt(guess) > JavaFXApplication.nToGuess) { 
      JavaFXApplication.nTries++; 
      gLabel.setText("Too High!"); 

     } else if (Integer.parseInt(guess) < JavaFXApplication.nToGuess) { 
      JavaFXApplication.nTries++; 
      gLabel.setText("Too Low!"); 

     } else if (Integer.parseInt(guess) == JavaFXApplication.nToGuess) { 
      if (JavaFXApplication.nTries > 1) { 
       gLabel.setText("Took you " + JavaFXApplication.nTries + " tries. Restarted."); 
       System.out.println("Took you " + JavaFXApplication.nTries + " tries. Restarted."); 
      } else if (JavaFXApplication.nTries == 0) { 
       gLabel.setText("You are a hacker."); 
       System.out.println("You are a hacker."); 
      } else if (JavaFXApplication.nTries == 1) { 
       gLabel.setText("It's taken you only 1 try."); 
       System.out.println("It's taken you only 1 try."); 
      } 
      JavaFXApplication.nTries = 0; 
      JavaFXApplication.rand = new Random(); 
      JavaFXApplication.nToGuess = JavaFXApplication.rand.nextInt(100); 
      System.out.println(JavaFXApplication.nToGuess); 
     } 
    } else if (source == rButton) { 
     JavaFXApplication.nTries = 0; 
     gLabel.setText("Game has been restarted."); 
     JavaFXApplication.rand = new Random(); 
     JavaFXApplication.nToGuess = JavaFXApplication.rand.nextInt(100); 
     System.out.println("Game restarted.\n" + JavaFXApplication.nToGuess); 
    } 
    gField.setText(null); 
} 

@Override 
public void initialize(URL url, ResourceBundle rb) { 
    assert gButton != null : "fx:id=\"myButton\" was not injected: check your FXML file 'simple.fxml'."; 
    assert rButton != null : "fx:id=\"myButton\" was not injected: check your FXML file 'simple.fxml'."; 
    assert colorBar != null : "fx:id=\"myButton\" was not injected: check your FXML file 'simple.fxml'."; 
    assert gLabel != null : "fx:id=\"myButton\" was not injected: check your FXML file 'simple.fxml'."; 
    assert gField != null : "fx:id=\"myButton\" was not injected: check your FXML file 'simple.fxml'."; 


} 

을 그리고 여기 내 JavaFXApplication.java있어

static int nTries = 0; 
static Random rand = new Random(); 
static int nToGuess = rand.nextInt(100); 
@Override 
public void start(Stage stage) throws Exception { 

    Parent root = FXMLLoader.load(getClass().getResource("FXMLDocument.fxml")); 

    Scene scene = new Scene(root); 
    stage.setScene(scene); 
    stage.show(); 
} 

/** 
* @param args the command line arguments 
*/ 
public static void main(String[] args) { 
    launch(args); 
} 
public static String nTriesTextGetter() { 
    return Integer.toString(nTries); 
} 

나는 스윙에서 당신도 행동을 사용해야한다는 것을 알고 있습니다. t 청취자와 EventQueue.invokeLater 그래서 EDT 스레드에서 논리가 실행되지 않으며 이것이 JavaFX를 사용하는 첫 번째 응용 프로그램입니다. 어떤 설명이라도 큰 도움이 될 것입니다.

Answer 1

이것은 스레딩과 관련이 없습니다. 텍스트가 아직 비어있을 때 gField 텍스트 필드의 텍스트를 정수로 변환하려고하면 NumberFormatException이 생성됩니다.

Answer 2

문자열의 크기 제한을 넘어서도이 문자열에 null 값이 포함되어 있으면이 오류 유형이 발생합니다.