我用tomcat运行jsp项目，为什么可以显示登录首页，但是后续的页面无法显示？数据库跟踪也无反应？

Question

怀疑是web.xml的问题
控制台没报错？

Answer 1

是登录页面，我跟踪数据库，但是没有反应。报错
HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception javax.servlet.ServletException
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:523)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
com.cherry.filesys.common.SetCharactorEncoding.doFilter(SetCharactorEncoding.java:23)
root cause java.lang.NullPointerException
com.cherry.filesys.persist.UserPersist.doQueryByName(UserPersist.java:38)
com.cherry.filesys.service.UserService.userLogin(UserService.java:9)
com.cherry.filesys.struts.action.LoginAction.execute(LoginAction.java:47)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
com.cherry.filesys.common.SetCharactorEncoding.doFilter(SetCharactorEncoding.java:23)
note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.
--------------------------------------------------------------------------------Apache Tomcat/5.0.28

Answer 2

查一下SetCharactorEncoding.java的doFilter方法的23行，看看是不是有空指针（java.lang.NullPointerException）的问题。或者把代码贴出来