任何人都可以解释我或建议解决以下问题吗？我在eclipse工作区有两个项目，在projectA这个类运行得很好：
public class Example extends JFrame {
public Example() {
setTitle("Simple example");
setSize(300, 200);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public static void main(String[] args) {
Example ex = new Example();
ex.setVisible(true);
}
}
在projectB中，相同的代码给出了以下错误：
2014-05-30 16:18:44.885 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x000000010fff729e Java_sun_java2d_opengl_CGLLayer_nativeCreateLayer + 119
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.886 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.887 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x000000011000014c Java_sun_lwawt_macosx_CPlatformView_nativeCreateView + 169
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
2 ??? 0x000000010c0f0275 0x0 + 4497277557
3 ??? 0x000000010c0f0158 0x0 + 4497277272
)
2014-05-30 16:18:44.887 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.888 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x00000001100004e4 Java_sun_lwawt_macosx_CPlatformWindow_nativeCreateNSWindow + 188
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
2 ??? 0x000000010c0f0275 0x0 + 4497277557
)
2014-05-30 16:18:44.889 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.897 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x0000000110005c28 Java_sun_lwawt_macosx_CPlatformComponent_nativeCreateComponent + 119
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.897 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.898 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x00000001100057dd Java_sun_lwawt_macosx_CPlatformWindow_nativeSetNSWindowTitle + 60
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
2 ??? 0x000000010c0f0158 0x0 + 4497277272
)
2014-05-30 16:18:44.899 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.899 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x000000011000504e Java_sun_lwawt_macosx_CPlatformWindow_nativeSetNSWindowStyleBits + 69
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.899 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.900 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x0000000110004a1f Java_sun_lwawt_macosx_CPlatformWindow_nativeSetNSWindowMinMax + 79
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.900 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.900 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x00000001100058e7 Java_sun_lwawt_macosx_CPlatformWindow_nativeGetNSWindowInsets + 72
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
2 ??? 0x000000010c0f0333 0x0 + 4497277747
3 ??? 0x000000010c0f09e1 0x0 + 4497279457
)
2014-05-30 16:18:44.901 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.911 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x0000000110004390 Java_sun_lwawt_macosx_CPlatformWindow_nativeSetNSWindowMinimizedIcon + 64
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.912 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.913 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x0000000110004159 Java_sun_lwawt_macosx_CPlatformWindow_nativeSynthesizeMouseEnteredExitedEvents + 59
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.913 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.914 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x0000000110006e20 Java_sun_lwawt_macosx_CCursorManager_nativeGetCursorPosition + 66
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
)
2014-05-30 16:18:44.914 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
2014-05-30 16:18:44.914 java[26656:507] Cocoa AWT: Running on AppKit thread 0 when not expected. (
0 liblwawt.dylib 0x000000011000504e Java_sun_lwawt_macosx_CPlatformWindow_nativeSetNSWindowStyleBits + 69
1 ??? 0x000000010c0fbf90 0x0 + 4497325968
2 ??? 0x000000010c0f0158 0x0 + 4497277272
3 ??? 0x000000010c0f0158 0x0 + 4497277272
)
2014-05-30 16:18:44.915 java[26656:507] Please file a bug report at http://java.net/jira/browse/MACOSX_PORT with this message and a reproducible test case.
在那个projectB我有很多其他类，都有正确的Java代码，其中一些主管运行得很好。但是，同样，在projectB中，如果我尝试运行代码，在现有主要内部（在没有摆动代码的情况下运行良好）中运行一些非常基本的摇摆窗口，它将运行应用程序，但我的JFrame赢了＆＃39 ;出现。
答案 0 :(得分：0)
import javax.swing.JFrame;
public class Example extends JFrame {
public Example() {
this.setTitle("Simple example");
this.setSize(300, 200);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
Example ex = new Example();
ex.setVisible(true);
}
}
我们在这里做的是扩展JFrame。示例IS-JFrame的子类，现在继承了它的所有功能。然后我们可以在构造函数方法（Example（））中使用JFrame及其超类中定义的setter方法，使用'this'来显式引用当前示例的当前实例。
有关'this'的信息，请参阅此处。