1。看个简单的程序先:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;public class Test extends JFrame {
private JTextArea txt = null;
public Test() {
txt = new JTextArea("hello word", 5, 50);
add(new JScrollPane(txt));
setLayout(new FlowLayout());
}
public static void main(String[] args) {
JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new Test();
frame.pack();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
输入中文看看,是否有异常?2。你把“JFrame.setDefaultLookAndFeelDecorated(true);”去掉再看一下是否有异常发生?3。知道什么原因麻烦通知我!!!
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;public class Test extends JFrame {
private JTextArea txt = null;
public Test() {
txt = new JTextArea("hello word", 5, 50);
add(new JScrollPane(txt));
setLayout(new FlowLayout());
}
public static void main(String[] args) {
JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new Test();
frame.pack();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
输入中文看看,是否有异常?2。你把“JFrame.setDefaultLookAndFeelDecorated(true);”去掉再看一下是否有异常发生?3。知道什么原因麻烦通知我!!!
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.util.Hashtable.get(Hashtable.java:336)
at javax.swing.KeyboardManager.registerMenuBar(KeyboardManager.java:263) at javax.swing.JMenuBar.addNotify(JMenuBar.java:679)
at java.awt.Container.addNotify(Container.java:2500)
at javax.swing.JComponent.addNotify(JComponent.java:4469)
at javax.swing.plaf.metal.MetalTitlePane.addNotify(MetalTitlePane.java:2
23)
at java.awt.Container.addNotify(Container.java:2500)
at javax.swing.JComponent.addNotify(JComponent.java:4469)
at java.awt.Container.addNotify(Container.java:2500)
at javax.swing.JComponent.addNotify(JComponent.java:4469)
at javax.swing.JRootPane.addNotify(JRootPane.java:680)
at java.awt.Container.addNotify(Container.java:2500)
at java.awt.Window.addNotify(Window.java:466)
at java.awt.Frame.addNotify(Frame.java:501)
at java.awt.Window.pack(Window.java:484)
at sun.awt.im.CompositionArea.<init>(CompositionArea.java:71)
at sun.awt.im.CompositionAreaHandler.createCompositionArea(CompositionAr
eaHandler.java:56)
at sun.awt.im.CompositionAreaHandler.inputMethodTextChanged(CompositionA
reaHandler.java:169)
at sun.awt.im.CompositionAreaHandler.processInputMethodEvent(Composition
AreaHandler.java:144)
at sun.awt.im.InputMethodContext.dispatchEvent(InputMethodContext.java:1
75)
at java.awt.Component.dispatchEventImpl(Component.java:3902)
at java.awt.Container.dispatchEventImpl(Container.java:2024)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchTh
read.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThre
ad.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149) at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
java version "1.5.0_07"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_07-b03)
Java HotSpot(TM) Client VM (build 1.5.0_07-b03, mixed mode, sharing)
光输入字符是不会异常的。
输入中文时,跟本不会弹出那个可以选字的框框。
jdk1.5以上版本存在 BUG ,jdk1.4的版本正常运行!