HTTP Status 500 - 这是怎么回事啊？

[zouwei221]

做了一个学生信息管理系统，需要链接整个Tomcat下的jsp、servlet，javabean和SQL的配置。我都配置完了可是运行的时候只要是和数据库有关系的界面就会出现以下东西。怎么回事啊？
求大神...
type Exception report

message

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

exception

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:372)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root cause

java.lang.NullPointerException
org.apache.jsp.chengji_jsp._jspService(chengji_jsp.java:91)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
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.


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Apache Tomcat/5.0.28

[麟儿]

是编译错误了。