HTTP Status 500 错误

HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception javax.servlet.ServletException: java.sql.SQLException: Column 'grade' not found.
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:535)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:433)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause java.sql.SQLException: Column 'grade' not found.
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:910)
com.mysql.jdbc.ResultSet.findColumn(ResultSet.java:987)
com.mysql.jdbc.ResultSet.getString(ResultSet.java:5584)
org.apache.commons.dbcp.DelegatingResultSet.getString(DelegatingResultSet.java:263)
org.apache.commons.dbcp.DelegatingResultSet.getString(DelegatingResultSet.java:263)
j2eebbs.User.getUserGrade(User.java:113)
j2eebbs.admin.action.AdminLoginAction.execute(AdminLoginAction.java:39)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.18 logs.