打开struts2.xml文件时提示 Could not open the editor: An unexpected exception解决方案

提示错误信息：Could not open the editor: An unexpected exception was thrown.

01	java.lang.NullPointerException

02	at com.genuitec.eclipse.struts.editor.modeler.model.StrutsConfigDiagram.processAction(StrutsConfigDiagram.java:574)

03	at com.genuitec.eclipse.struts.editor.modeler.model.StrutsConfigDiagram.synchronizeDiagram(StrutsConfigDiagram.java:479)

04	at com.genuitec.eclipse.struts.editor.modeler.model.StrutsConfigDiagram.differedSynchronize(StrutsConfigDiagram.java:120)

05	at com.genuitec.eclipse.struts.editor.multipage.StrutsConfigEditor.createPages(StrutsConfigEditor.java:296)

06	at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:357)

07	at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:662)

08	at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:462)

09	at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595)

10	at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:313)

11	at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:180)

12	at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:270)

13	at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)

14	at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:473)

15	at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1256)

16	at org.eclipse.ui.internal.PartStack.setSelection(PartStack.java:1209)

17	at org.eclipse.ui.internal.PartStack.showPart(PartStack.java:1608)

18	at org.eclipse.ui.internal.PartStack.add(PartStack.java:499)

19	at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:103)

20	at org.eclipse.ui.internal.PartStack.add(PartStack.java:485)

21	at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:112)......

解决方法：关闭MyEclipse，打开项目，找到当前工程的src目录(和struts.xml同级目录)，会发现有一个文件，名字为“.struts.mex”。删除这个文件，启动MyEclipse，然后双击，或者右键，选择用“MyEclipse Struts Config Editor”打开struts.xml文件