校网出现 500 Servlet Exception

问题描述：

我访问学校网站
http://210.26.124.220:8081/jwsys/servlet/StudentLogin
时出现的错误如下：
500 Servlet Exception
java.lang.NullPointerException
at com.hnxl.jwsys.common.dbo.DbResultSetChange.rsChangeVector(DbResultSetChange.java:66)
at com.hnxl.jwsys.common.dbo.DbAccessEx.getExecuteQueryVector(DbAccessEx.java:73)
at com.hnxl.jwsys.student.student_DbAccess.getRSInVector(student_DbAccess.java:62)
at com.hnxl.jwsys.student.VerifyStudentPwd.getClassOfStudent(VerifyStudentPwd.java:84)
at servlet.student.StudentLoginServlet.doGet(StudentLoginServlet.java:59)
at servlet.student.StudentLoginServlet.doPost(StudentLoginServlet.java:137)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:165)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:103)
at com.caucho.server.http.FilterChainServlet.doFilter(FilterChainServlet.java:96)
at com.caucho.server.http.Invocation.service(Invocation.java:312)
at com.caucho.server.http.CacheInvocation.service(CacheInvocation.java:135)
at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:244)
at com.caucho.server.http.HttpRequest.handleConnection(HttpRequest.java:163)
at com.caucho.server.TcpConnection.run(TcpConnection.java:137)
at java.lang.Thread.run(Thread.java:479)

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Resin 2.1.6 (built Fri Nov 8 08:18:18 PST 2002)
急救下 系统时间是合适的 可是就是出这个问题 我都晕死了

问题解答：

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