500 Servlet Exception

java.lang.NullPointerException at zhjw.auth.AuthUser.userLoginCheck(AuthUser.java:82) at zhjw.login.action.LoginAction.execute(LoginAction.java:46) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397) at javax.servlet.http.HttpServlet.service(HttpServlet.java:115) at javax.servlet.http.HttpServlet.service(HttpServlet.java:92) at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:106) at zhjw.util.filter.CharacterEncoding.doFilter(CharacterEncoding.java:81) at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70) at zhjw.util.filter.UserAuthBase.doFilter(UserAuthBase.java:39) at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70) at zhjw.util.filter.newfilter.UrpsoftFilter.doFilter(UrpsoftFilter.java:96) at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70) at org.thcic.filters.RoamFilter.doFilter(RoamFilter.java:113) at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70) at zhjw.util.filter.JsFilter.doFilter(JsFilter.java:97) at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:70) at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:173) at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:229) at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:274) at com.caucho.server.port.TcpConnection.run(TcpConnection.java:514) at com.caucho.util.ThreadPool.runTasks(ThreadPool.java:520) at com.caucho.util.ThreadPool.run(ThreadPool.java:442) at java.lang.Thread.run(Thread.java:662)