java - 在 JFrame 中键入会出现错误

Question

所以我遇到了一个问题，如果我只是单击没有组件的框架中的一个键，它会给我一个错误。我试过没有组件，但这个错误不断出现，即使没有组件。即使我尝试了另一个新的，这个错误仍然发生。当我单击框架中的某个键时，它总是出现。

2014-07-31 14:13:28.281 java[52432:507] An uncaught exception was raised
2014-07-31 14:13:28.282 java[52432:507] java.lang.NullPointerException
2014-07-31 14:13:28.284 java[52432:507] (
    0   CoreFoundation                      0x00007fff8a62e25c __exceptionPreprocess + 172
    1   libobjc.A.dylib                     0x00007fff8baf3e75 objc_exception_throw + 43
    2   CoreFoundation                      0x00007fff8a62de09 -[NSException raise] + 9
    3   JavaNativeFoundation                0x000000010ed0a457 JNFCallObjectMethod + 212
    4   liblwawt.dylib                      0x000000010f53b913 -[AWTView attributedSubstringForProposedRange:actualRange:] + 78
    5   AppKit                              0x00007fff8ad6c75d -[NSTextInputContext handleTSMEvent:] + 3476
    6   AppKit                              0x00007fff8ad6b9a5 _NSTSMEventHandler + 205
    7   HIToolbox                           0x00007fff88da81d4 _ZL23DispatchEventToHandlersP14EventTargetRecP14OpaqueEventRefP14HandlerCallRec + 892
    8   HIToolbox                           0x00007fff88da7787 _ZL30SendEventToEventTargetInternalP14OpaqueEventRefP20OpaqueEventTargetRefP14HandlerCallRec + 385
    9   HIToolbox                           0x00007fff88dbb880 SendEventToEventTarget + 40
    10  HIToolbox                           0x00007fff88dfcd0d SendTSMEvent + 33
    11  HIToolbox                           0x00007fff88faa5ff SendTextInputEvent + 1028
    12  HIToolbox                           0x00007fff88ff589c -[IMKInputSession _copyUniCharsForRange:intoBuffer:ofLength:] + 268
    13  HIToolbox                           0x00007fff88ff596b -[IMKInputSession _coreAttributesFromRange:whichAttributes:actualRange:] + 137
    14  HIToolbox                           0x00007fff88ff6a5c -[IMKInputSession attributedSubstringFromRange:] + 89
    15  CoreFoundation                      0x00007fff8a519bec __invoking___ + 140
    16  CoreFoundation                      0x00007fff8a519a54 -[NSInvocation invoke] + 308
    17  CoreFoundation                      0x00007fff8a5bc5e6 -[NSInvocation invokeWithTarget:] + 54
    18  CoreFoundation                      0x00007fff8a58c1c4 ___forwarding___ + 452
    19  CoreFoundation                      0x00007fff8a58bf78 _CF_forwarding_prep_0 + 120
    20  CoreFoundation                      0x00007fff8a519bec __invoking___ + 140
    21  CoreFoundation                      0x00007fff8a519a54 -[NSInvocation invoke] + 308
    22  Foundation                          0x00007fff88310d47 -[NSConnection dispatchInvocation:] + 135
    23  Foundation                          0x00007fff88310a0d -[NSConnection handleRequest:sequence:] + 1434
    24  Foundation                          0x00007fff882b7d50 -[NSConnection handlePortCoder:] + 652
    25  Foundation                          0x00007fff882b7688 -[NSConnection dispatchWithComponents:] + 50
    26  Foundation                          0x00007fff8829bf38 __NSFireMachPort + 257
    27  CoreFoundation                      0x00007fff8a55fb44 __CFMachPortPerform + 388
    28  CoreFoundation                      0x00007fff8a55f9a9 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 41
    29  CoreFoundation                      0x00007fff8a55f91e __CFRunLoopDoSource1 + 478
    30  CoreFoundation                      0x00007fff8a550a16 __CFRunLoopRun + 1830
    31  CoreFoundation                      0x00007fff8a5500b5 CFRunLoopRunSpecific + 309
    32  Foundation                          0x00007fff882b406e -[NSConnection sendInvocation:internal:] + 1965
    33  CoreFoundation                      0x00007fff8a58c1c4 ___forwarding___ + 452
    34  CoreFoundation                      0x00007fff8a58bf78 _CF_forwarding_prep_0 + 120
    35  HIToolbox                           0x00007fff88ff1b3d -[IMKInputSession handleEvent:] + 946
    36  HIToolbox                           0x00007fff88fb51d8 IMKInputSessionProcessEventRef + 45
    37  HIToolbox                           0x00007fff88fb4792 InputMethodInstanceProcessEventRef + 100
    38  HIToolbox                           0x00007fff88fa9d4f TSMEventToInputMethod + 131
    39  HIToolbox                           0x00007fff88dfc4a0 TSMKeyEvent + 301
    40  HIToolbox                           0x00007fff88de92b7 TSMProcessRawKeyEvent + 3807
    41  AppKit                              0x00007fff8ad6b1f0 -[NSTextInputContext handleEvent:] + 731
    42  AppKit                              0x00007fff8ad4aabd -[NSView interpretKeyEvents:] + 180
    43  liblwawt.dylib                      0x000000010f53a880 -[AWTView keyDown:] + 85
    44  AppKit                              0x00007fff8ad1765b -[NSWindow sendEvent:] + 1843
    45  liblwawt.dylib                      0x000000010f53e2f5 -[AWTWindow_Normal sendEvent:] + 86
    46  AppKit                              0x00007fff8acb8c42 -[NSApplication sendEvent:] + 3395
    47  libosxapp.dylib                     0x000000010f5d666f -[NSApplicationAWT sendEvent:] + 179
    48  AppKit                              0x00007fff8ab08b89 -[NSApplication run] + 646
    49  libosxapp.dylib                     0x000000010f5d6557 +[NSApplicationAWT runAWTLoopWithApp:] + 156
    50  liblwawt.dylib                      0x000000010f52eba9 -[AWTStarter starter:] + 873
    51  Foundation                          0x00007fff8829513e __NSThreadPerformPerform + 229
    52  CoreFoundation                      0x00007fff8a55f731 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    53  CoreFoundation                      0x00007fff8a550ea2 __CFRunLoopDoSources0 + 242
    54  CoreFoundation                      0x00007fff8a55062f __CFRunLoopRun + 831
    55  CoreFoundation                      0x00007fff8a5500b5 CFRunLoopRunSpecific + 309
    56  java                                0x00000001065313b0 CreateExecutionEnvironment + 871
    57  java                                0x000000010652bb5c JLI_Launch + 1952
    58  java                                0x000000010653170d main + 101
    59  java                                0x000000010652b3b4 start + 52
    60  ???                                 0x0000000000000005 0x0 + 5
)

代码:

    public class TestGame extends JFrame{

       public static void main(String[] args){
          new TestGame();
       }

       public TestGame(){
           this.setSize(1024, 768);
           this.setLocationRelativeTo(null);
           this.setResizable(true);
           this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
           this.setVisible(true);
        }
   }

Answer 1

我在带有 Java 7 或 8 的 Windows 8 上没有得到这个。

也许以推荐的方式启动它:

public class TestGame {
    public void launch() {
        JFrame frame = new JFrame();

        frame.setSize(1024, 768);
        frame.setLocationRelativeTo(null);
        frame.setResizable(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new TestGame().launch();
            }
        });
    }
}