java.lang.NullPointerException at com.genuitec.eclipse.ast.deploy.core.Deployment

项目启动的时候总是提示以下错误：

java.lang.NullPointerException    at com.genuitec.eclipse.ast.deploy.core.Deployment.<init>(Unknown Source)    at com.genuitec.eclipse.ast.deploy.core.ModuleDeployment.<init>(Unknown Source)    at com.genuitec.eclipse.ast.deploy.core.WebDeployment.<init>(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.<init>(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.<init>(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.createControl(PartStack.java:662)    at org.eclipse.ui.internal.PartStack.createControl(PartStack.java:570)    at org.eclipse.ui.internal.PartSashContainer.createControl(PartSashContainer.java:568)    at org.eclipse.ui.internal.PerspectiveHelper.activate(PerspectiveHelper.java:272)    at org.eclipse.ui.internal.Perspective.onActivate(Perspective.java:981)    at org.eclipse.ui.internal.WorkbenchPage.setPerspective(WorkbenchPage.java:3713)    at org.eclipse.ui.internal.WorkbenchPage.busySetPerspective(WorkbenchPage.java:1115)    at org.eclipse.ui.internal.WorkbenchPage.access$16(WorkbenchPage.java:1099)    at org.eclipse.ui.internal.WorkbenchPage$19.run(WorkbenchPage.java:3814)    at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)    at org.eclipse.ui.internal.WorkbenchPage.setPerspective(WorkbenchPage.java:3812)    at org.eclipse.ui.internal.PerspectiveBarContributionItem.select(PerspectiveBarContributionItem.java:124)    at org.eclipse.ui.internal.PerspectiveBarManager$1.widgetSelected(PerspectiveBarManager.java:129)    at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:240)    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)

给出如下推测：错误提示发生在myeclipse启动之后，tomcat启动之前，所以，可以确定问题发生在myeclipse初始化工作空间的时候。

查资料后发现问题原因如下：
我们使用myeclipse自动部署web项目时会设置服务器的位置，而部署的相关配置会存储在myeclipse工作目录下的“.metadata.plugins\org.eclipse.core.runtime.settings\com.genuitec.eclip”，因此当我们更换了服务器的位置时，在进行部署的时候就会报错，这是我们的解决办法。

第一种方式：
1、关闭myeclipse
2、进入工作空间“.metadata.plugins\org.eclipse.core.runtime.settings”，比如我本机工作空间“D:\java\Workspaces\MyEclipse.metadata.plugins\org.eclipse.core.runtime.settings”，删除 com.genuitec.eclipse.ast.deploy.core.prefs文件，然后打开myeclipse重新部署即可。

第二种方式：
把web工程建在另外的工作空间中。