he superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

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Description Resource Path Location Type

The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Pathadd.jsp /dwz-java/WebContent/WEB-INF/jsp/management/newsline 1 JSP Problem

在出现此错误的项目上单击鼠标右键》Build Path》Configure Build Path

2017-04-21更新

到了添加Server Library步骤时，里面是空选项，没有Tomcat 7.0选择，怎么办？

参考：eclipse 服务器配置之添加 Tomcat 服务器