Conditional forward in JSP

Question

Following is my jsp page. I am trying to forward to another jsp depending on the conditions.
<%@ taglib uri="struts-logic" prefix="logic" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%
     String u = (String)session.getAttribute("userID");
     String seibel = (String)session.getAttribute("seibel");
    System.out.println(u);
    System.out.println(seibel);
     if(seibel.equals("true"))
      {%>
      <jsp:forward page = "AutoLogin.jsp"/>;
      <%}     
     else
     %>
       <logic:redirect forward="logon"/> ;     
<%
%>When the if condition fails, the else part does not get executed. The error I get is as follows.
[exec] <Dec 28, 2007 11:48:13 AM IST> <Error> <HTTP> <101017> <[ServletContext(id=7535615,name=csr-gema,context-path=)] Root cause of ServletException
[exec] java.lang.NullPointerException
[exec] at jsp_servlet.__forwardtogema._jspService(__forwardtogema.java:107)
[exec] at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
[exec] at weblogic.servlet.internal.ServletStubImpl$ServletInvocationAction.run(ServletStubImpl.java:1094)
[exec] at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:437)
[exec] at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:481)
[exec] at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:319)
[exec] at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:5626)
[exec] at weblogic.security.service.SecurityServiceManager.runAs(SecurityServiceManager.java:685)
[exec] at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:3213)
[exec] at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:2555)
[exec] at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:251)
[exec] at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:219)
[exec] >
Any inputs? Please reply.

Answer 1

As mentioned, seibel must be null. Change your code so it's like this
     if(seibel == null || seibel.equals("true"))
      {%>
      <jsp:forward page = "AutoLogin.jsp"/>;
      <%}     
     else
     %>
       <logic:redirect forward="logon"/> ;     
<%
}However depending on what you are trying to do this may just hide your problem by
short circuiting when seibel is null. If seibel should not be null then your problem is elsewhere.