当前页面: 开发资料首页 → JSP 专题 → 有没有人给我解释一下这个错误呀？

有没有人给我解释一下这个错误呀？

摘要: 有没有人给我解释一下这个错误呀？

HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

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:526)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:467)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1422)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:523)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root cause

java.lang.NullPointerException
logon.LogonAction.execute(LogonAction.java:253)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:465)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1422)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:523)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.

---

NullPointer啊NullPointer，要学会看日志。

---

空指针引用啊

---

你有值没有取到，通常是request.getParameter("***")引起的

---

当然还有数据库没有连接上连接，没有创建Connection却close()，没有创建Statement却close()，没有创建ResultSet却close()等等。

---

看看你的LogonAction.java 253行

---

问题解决
没有strut包

---