jsp代码在tomcat部署提示错误500

Question

HTTP Status 500 -

type Exception report

message

description The server encountered an internal error that prevented it from fulfilling this request.

exception

java.lang.NullPointerException
cn.edu.jstu.jsjxy.fbh.dao.impl.UserDaoImpl.getUserByName(UserDaoImpl.java:15)
cn.edu.jstu.jsjxy.fbh.servlet.LoginServlet.doPost(LoginServlet.java:25)
javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
cn.edu.jstu.jsjxy.fbh.filter.AuthorityFilter.doFilter(AuthorityFilter.java:33)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.44 logs.

Apache Tomcat/6.0.44

Answer 1

java.lang.NullPointerException这这句话可以看出应该是空指针，cn.edu.jstu.jsjxy.fbh.dao.impl.UserDaoImpl.getUserByName(UserDaoImpl.java:15)在传递参数时，存在空值的参数