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今天一早起来打开myeclipse10准备学习，但是令人想不到的情况发生了，servers框下竟然报错了：Could not create the view: An unexpected exception was thrown.

如图：

具体错误信息如下：

java.lang.NullPointerException	at com.genuitec.eclipse.ast.deploy.core.Deployment.
   
    (Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.ModuleDeployment.
    
     (Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.WebDeployment.
     
      (Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.Deployment.create(Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.DeploymentManager.loadFromPreferences(Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.DeploymentManager.init(Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.DeploymentManager.
      
       (Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.DeploymentManager.getDefault(Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.ui.ServerTreeViewer$ServerTreeContentProvider.inputChanged(Unknown Source)	at org.eclipse.jface.viewers.ContentViewer.setInput(ContentViewer.java:276)	at org.eclipse.jface.viewers.StructuredViewer.setInput(StructuredViewer.java:1690)	at com.genuitec.eclipse.ast.deploy.core.ui.ServerTreeViewer.
       
        (Unknown Source)	at com.genuitec.eclipse.ast.deploy.core.ui.ServerView.createPartControl(Unknown Source)	at org.eclipse.ui.internal.ViewReference.createPartHelper(ViewReference.java:375)	at org.eclipse.ui.internal.ViewReference.createPart(ViewReference.java:229)	at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595)	at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:313)	at org.eclipse.ui.internal.ViewPane.setVisible(ViewPane.java:534)	at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:180)	at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:270)	at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)	at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:473)	at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1245)	at org.eclipse.ui.internal.PartStack.setSelection(PartStack.java:1198)	at org.eclipse.ui.internal.PartStack.presentationSelectionChanged(PartStack.java:834)	at org.eclipse.ui.internal.PartStack.access$1(PartStack.java:823)	at org.eclipse.ui.internal.PartStack$1.selectPart(PartStack.java:137)	at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation$1.handleEvent(TabbedStackPresentation.java:133)	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:269)	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:278)	at org.eclipse.ui.internal.presentations.defaultpresentation.DefaultTabFolder.access$1(DefaultTabFolder.java:1)	at org.eclipse.ui.internal.presentations.defaultpresentation.DefaultTabFolder$2.handleEvent(DefaultTabFolder.java:88)	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1077)	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1062)	at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:774)	at org.eclipse.swt.custom.CTabFolder.setSelection(CTabFolder.java:2746)	at org.eclipse.swt.custom.CTabFolder.onMouse(CTabFolder.java:1433)	at org.eclipse.swt.custom.CTabFolder$1.handleEvent(CTabFolder.java:257)	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4165)	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3754)	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701)	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665)	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499)	at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679)	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668)	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:123)	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)	at java.lang.reflect.Method.invoke(Method.java:597)	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)	at org.eclipse.equinox.launcher.Main.run(Main.java:1410)	at org.eclipse.equinox.launcher.Main.main(Main.java:1386)	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)	at java.lang.reflect.Method.invoke(Method.java:597)	at com.genuitec.pulse.eclipse.launcher.Main.main(Main.java:110)
       
      
     
    
   

错误信息分析：

这个错误发生在servers中，应该不是代码问题，可能是myeclipse在初始化工作空间workspace的时候，发生了异常。

错误信息第一行是这样的：at com.genuitec.eclipse.ast.deploy.core.Deployment.<init>(Unknown Source)

于是到工作空间下面的spring_workSpace\.metadata\.plugins\org.eclipse.core.runtime\.settings地址，

找到名称为：com.genuitec.eclipse.ast.deploy.core.prefs的文件，如图：

打开发现里面是项目的信息，如：contextRoot，deployIsOverProject，deploymentPath，isDeployed，isExploded...

等等，这些项目信息中的一些我已经关闭了，所以导致找不到，报java.lang.NullPointerException 。 

解决方案就是：将次文件删除，然后重新启动myeclipse10，这次一切正常！！