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

maven构建的web工程（war打包）,新建jsp文件是出现叉叉，错误提示为The superclass javax.servlet.http.HttpServlet was not found on the Java Build Path   。解决办法就是：右键点击错误的（上面有叉叉）的web工程，而后Build Path ，Configure Build Path ，Libraies，add Libray ，选择server running time 而后next，finish。