今天早上吃完早餐來公司上班，打開電腦，輸入密碼，123456。。。。。嗯……，再打開myeclipse，duang。。。duang。。。duang。。。。tomcat空指針異常，tmd我這暴脾氣昨天還好好的今天就給我來這一套，擱我五年前那暴脾氣，早就卸了你，時間成就了我的成熟，ok，不扯了，搞定這空指針異常是我義不容辭的責任；
附上異常日志：
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)
這個問題的出現是在啟動myeclipse之后出現的，這時還沒有啟動tomcat，因此可以排除tomcat中項目代碼問題。應該是myeclipse在初始化工作空間workspace 的時候
出的問題，仔細看，發現有一條 at com.genuitec.eclipse.ast.deploy.core.Deployment.這個錯誤；
於是到工作空間下面的C:\Users\Administrator\Workspaces\.metadata\.plugins\org.eclipse.core.runtime\.settings目錄下面找到了名稱為com.genuitec.eclipse.ast.deploy.core.prefs的文件，打開文件一開，哈哈，原來里面都是原來的一些項目信息，怪不得會報java.lang.NullPointerException錯誤呢。果斷將此文件刪除，重啟myeclipse10問題解決