有时候说是nullponiter错误~
有时候是别的？请问这怎么解决？

你是在有wtp插件的eclipse上面安装的myeclipse吧？
两个插件有冲突的。。。。删掉wtp就好了。

不是。我是用的all in one
我装了5个版本了都是这种问题

java.lang.NullPointerException
    at com.genuitec.eclipse.webdesigner3.src.SourceEditSystem.getSourceDocument(SourceEditSystem.java:233)
    at com.genuitec.eclipse.webdesigner3.design.DesignEditSystem.synchronize(DesignEditSystem.java:167)
    at com.genuitec.eclipse.webdesigner3.AbstractEditSystem.setSynchronized(AbstractEditSystem.java:24)
    at com.genuitec.eclipse.webdesigner3.WebDesigner3.setSynchronized(WebDesigner3.java:113)
    at com.genuitec.eclipse.webdesigner3.editors.WebDesignerMultiPageEditor.checkSynchronization(WebDesignerMultiPageEditor.java:936)
    at com.genuitec.eclipse.webdesigner3.editors.WebDesignerMultiPageEditor.access$6(WebDesignerMultiPageEditor.java:932)
    at com.genuitec.eclipse.webdesigner3.editors.WebDesignerMultiPageEditor$10.run(WebDesignerMultiPageEditor.java:909)
    at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
    at com.genuitec.eclipse.webdesigner3.editors.WebDesignerMultiPageEditor.designPageChange(WebDesignerMultiPageEditor.java:907)
    at com.genuitec.eclipse.webdesigner3.editors.WebDesignerMultiPageEditor.pageChange(WebDesignerMultiPageEditor.java:881)
    at org.eclipse.ui.part.MultiPageEditorPart.setActivePage(MultiPageEditorPart.java:697)
    at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:287)
    at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:661)
    at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:426)
    at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:592)
    at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:263)
    at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2739)
    at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2651)
    at org.eclipse.ui.internal.WorkbenchPage.access$13(WorkbenchPage.java:2643)
    at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:2595)
    at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
    at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2590)
    at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2574)
    at org.eclipse.ui.actions.OpenWithMenu.openEditor(OpenWithMenu.java:340)
    at org.eclipse.ui.actions.OpenWithMenu.access$0(OpenWithMenu.java:328)
    at org.eclipse.ui.actions.OpenWithMenu$3.handleEvent(OpenWithMenu.java:226)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:938)
    at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3682)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3293)
    at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2389)
    at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2353)
    at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2219)
    at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:466)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:289)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:461)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:106)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:169)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:106)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:76)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:363)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:508)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:447)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1173)

我以前好像也遇到过这个问题。
解决办法是到安装路径下面删除一个jar文件，具体哪个我给忘了
你搜一下吧。
6.5我装了下，好像没什么问题。也好久没写jsp了，。。。

大哥，搜了n遍了，都没找着呢~

试试这里的解决办法

http://www.

试了，不行~
还是.NullPointerException