"AWT-EventQueue-2" 错误

Question

Exception in thread "AWT-EventQueue-2" java.lang.NullPointerException
at java.awt.Container.addImpl(Unknown Source)
at java.awt.Container.add(Unknown Source)
at javax.swing.JFrame.addImpl(Unknown Source)
at java.awt.Container.add(Unknown Source)
at com.kvm.FloatToolbar$1.actionPerformed(FloatToolbar.java:221)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
FloatToolbar的221行上面就是做了
helpFrm.add(help.getScroller(),BorderLayout.CENTER);这样的一个操作
而help.getScroller()是一个滚动条,而JScrollPane中添加的是一个JEditorPane,JEditorPane加载的是一个本地的网页
我的这个程序在Eclipse中用Applet运行正常,放到网页上去就出错

Answer 1

NullPointerException,你找下,哪个对象是null.我无法调试,出现这个问题的原因很多.你先找到原因,再找解决方法

Answer 2

如果能够调试我就不发贴了,在Eclipse正常

Answer 3

是不是刚开始 help.getScroller() 是空啊..

Answer 4

 at com.kvm.FloatToolbar$1.actionPerformed(FloatToolbar.java:221)

Answer 5

我在想是不是用JEditorPane来加载网页通过applet来运行会有问题?因为你们所说的在Eclipse中能不会为空什么的,help.getScroller()里面也有值

Answer 6

原因找出，
由于打包到网页上，网页传递给applet的参数不对导致url加载失败所有就Scroller为空的现象
给分