X11 window error using swing package?

[Chao Liu]

Hello,  I used javax.swing.tree and other package to show a simple tree. The program is ok in windows,but meet error in linux. the error information is listed in the following: Exception in thread "main" java.lang.InternalError: Can't connect to X11 window server usi ng ':0.0' as the value of the DISPLAY variable.         at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)         at sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:58)         at java.lang.Class.forName0(Native Method)         at java.lang.Class.forName(Class.java:120)         at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.ja va:58)         at java.awt.Window.<init>(Window.java:186)         at java.awt.Frame.<init>(Frame.java:315)         at java.awt.Frame.<init>(Frame.java:294)         at javax.swing.JFrame.<init>(JFrame.java:174)         at tree.<init>(tree.java:33)         at tree.main(tree.java:68)   And I have run the program in Xwin,the error is still. And it is strange that whether I login into linux in local computer or from remote computer,the error information is same.