I've assigned unique values for each error. So the exact error it display as
"error occured 56 : java.lang.NullPointerException"
I have found the area of the error. but i couldn't solve it.
My codings are as follows
Code:
<html>
<%@ page import="INCLUDES.DBConnection"%>
<%@ page import="java.sql.*"%>
<%@ page import="java.io.*"%>
<jsp:useBean id="DB" scope="page" class="INCLUDES.DBConnection"/>
<jsp:setProperty name="DB" property="*"/>
<jsp:useBean id="DB1" scope="page" class="INCLUDES.DBConnection"/>
<jsp:setProperty name="DB1" property="*"/>
<jsp:useBean id="DB2" scope="page" class="INCLUDES.DBConnection"/>
<jsp:setProperty name="DB2" property="*"/>
<%
String dbase=(String)session.getAttribute("dbase");
String trainee_id=(String)session.getAttribute("trainee_id");
String user_name=(String)session.getAttribute("user_name");
if(user_name==null)
{
response.sendRedirect("course_list_index2.jsp");
}
int attempt_id=Integer.parseInt((String)session.getAttribute("attempt_id"));
int number_of_questions=Integer.parseInt((String)session.getAttribute("number_of_questions"));
int course_id=Integer.parseInt((String)session.getAttribute("course_id"));
int paper_id=Integer.parseInt((String)session.getAttribute("paper_id"));
String statement=null;
ResultSet objRs=null;
ResultSet objRsQNo=null;
ResultSet objRsQ=null;
int no_of_papers=0,paper_no=0;
String course_name="",trainee_name="",paper_name="";
try
{
statement="select * from x_master_elearning_user u,x_master_trainee_detail_online t,x_masterListOfCourses c ,x_masterListOfPapers p where p.course_id=c.course_id and c.course_id=t.course_id and t.user_name=u.user_name and c.course_id=" + course_id + " and u.user_name='" + user_name + "' and p.paper_id=" + paper_id;
DB.setStatement(statement);
objRs=(ResultSet)DB.result();
if(objRs.next())
{
course_name=objRs.getString("course_name");
trainee_name=objRs.getString("first_name");
paper_name=objRs.getString("paper_name");
no_of_papers=objRs.getInt("no_of_papers");
paper_no=objRs.getInt("paper_no");
}
}
catch(Exception e)
{
out.print("error occured 1 :" + e);
}
int i=0;
if(request.getParameter("question_no")==null)
{
i=1;
}
else
{
i=Integer.parseInt(request.getParameter("question_no"))+1;
}
try
{
statement="select * from results where paper_id=" + paper_id + " and course_id=" + course_id + " and trainee_id='" + trainee_id + "'";
DB1.setStatement(statement);
objRsQNo=(ResultSet)DB1.result();
if(objRsQNo.next())
{
if(i<= number_of_questions)
{
statement="select * from x_masterListOfQuestions where paper_id=" + paper_id + " and question_id=" + objRsQNo.getInt("qn" + i);
DB2.setStatement(statement);
objRsQ=(ResultSet)DB2.result();
}
}
}
catch(Exception e)
{
out.print("error occured 22 :" + e);
}
%>
<head>
<LINK href="theme/Master.css" rel="stylesheet" type="text/css">
<LINK rel="stylesheet" type="text/css" href="mystyle.css">
<TITLE>Help and Support</TITLE>
<SCRIPT language="JavaScript" src="ajaxfiles/ajaxfunction.js"></SCRIPT>
</HEAD>
<BODY class="backgrounpicture" style="margin:0px">
<script src="topmenu.js"></script>
<form method="post" action="exam_question_insert.jsp" >
<input type="hidden" name="question_no" value=<%=i%>>
<table width="75%" align="right" >
<tr>
<td colspan="3"><hr color="#FFFFff" noshade size="1"></td>
</tr>
<%
try
{
if(objRsQ.next())
{
%>
<tr >
<td width="9%" class="infoLabel">Q No.<strong><%=i%></strong></td>
<td colspan="2" class="infoValue"><%=objRsQ.getString("question")%></td>
</tr>
<tr>
<td> </td>
<td colspan="2" class="infoValue"> <input type="radio" name="choice<%=i%>" value=1>
<%=objRsQ.getString("choice1")%></td>
</tr>
<tr>
<td> </td>
<td colspan="2" class="infoValue"> <input type="radio" name="choice<%=i%>" value=2>
<%=objRsQ.getString("choice2")%></td>
</tr>
<tr>
<td> </td>
<td colspan="2" class="infoValue"> <input type="radio" name="choice<%=i%>" value=3>
<%=objRsQ.getString("choice3")%></td>
</tr>
<tr>
<td> </td>
<td colspan="2" class="infoValue"> <input type="radio" name="choice<%=i%>" value=4>
<%=objRsQ.getString("choice4")%></td>
</tr>
<%
}
}
catch(Exception e)
{
out.print("error occured 56 : " + e);
}
%>
<tr>
<td colspan="3"><hr color="#FFFFff" noshade size="1"></td>
</tr>
<tr>
<td align=center> </td>
<td align="right">
<%if(i== number_of_questions)
{
%>
<div align="right">
<input type="submit" value="Finish" style="font-size:13pt;" name="submit" onClick="return fnConfirm()">
<%
}
else
{
%>
<input type="submit" value="Next" style="font-size:13pt;" name="submit">
<%
}
%>
</div></td>
<td width="47%" align="right"><input type="submit" value="Review" style="font-size:13pt" name="submit"></td>
</tr>
</table>
</form>
</body>
</html>