HTTP Status 500 求助

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
casecom.Service.LoginService.checkPassword(LoginService.java:18)
casecom.Servlet.Servlet.doPost(Servlet.java:74)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.77 logs.

Apache Tomcat/7.0.77
java的课程作业，这是最后一步了，非常心碎，求大神解决！

Answer 1

服务端代码错误，空指针，错误在LoginService这个类的第18行。你仔细看看