i am creating a jsp page that does the following:
select record marks from database
enable editing of each record
saving the edits of record
everything works well until i click on the save button to save edits.
it saves well but unable to refresh the page to show the new updates made in the table.
it shows this error: java.lang.IllegalStateException:Cannot call sendRedirect() after the response has been committed.
please what is causing the error when i press on the save button.
the full contents of the jsp page is below:
<html>
<head>
<title>stage 2 - arts</title>
<link rel="stylesheet" href="mycss/primary_subject_style.css" type="text/css"/>
</head>
<body>
<center><h5>CREATIVE ARTS</h5></center>
<div class="container">
<div class="panel">
<div class="for_table_head">
<table class="table-head">
<thead>
<tr>
<th><input type="hidden" name="id"></th>
<th style="width: 90px;">name</th>
<th>class</th>
<th>exam</th>
<th>total</th>
<th class="text-center">action</th>
</tr>
</thead>
</table>
</div>
<div class="for_table">
<table class="table">
<tbody>
<%
connector co=new connector();
Connection con=null;ResultSet rs=null; PreparedStatement pst=null;
con=connector.db_connect();
String data_search=null;
//str_active=request.getParameter("s_stream");
data_search ="select ID,Name,Creative_Arts,Creative_Arts_Exam,Creative_Arts_Total from class2 order by Name ASC";
String sql=data_search;
pst=con.prepareStatement(sql);
rs=pst.executeQuery();
while(rs.next()){
%>
<tr>
<td><input type="hidden" name="s_id" value='<%=rs.getString("ID")%>'/></td>
<td style="width: 100px;"><%=rs.getString("Name")%></td>
<td><%=rs.getString("Creative_Arts")%></td>
<td style="color: #3c78c9;"><%=rs.getString("Creative_Arts_Exam")%></td>
<td style="color: #047907;"><%=rs.getString("Creative_Arts_Total")%></td>
<td>
<form action="stage2_arts.jsp" method="post" >
<button style="width:38px;height:20px;background:transparent;border:none;cursor:pointer;color:#d58007;padding-left:0;"
type="submit" name="st_id" value='<%=rs.getString("ID")%>'>edit</button><br/>
</form>
</td>
</tr>
<%
}
%>
</tbody>
</table>
</div>
//suspected part causing the error :
<form action="stage2_arts.jsp" method="post">
<%
String stud_id=request.getParameter("st_id");
String srec="select ID,Name from class2 where ID='"+stud_id+"'";
pst=con.prepareStatement(srec);
rs=pst.executeQuery();
if(rs.next()){
%>
<div class="entry_box">
<div class="student_name">
<input type="hidden" name="s_id" value='<%=rs.getString("ID")%>' /><br>
<label>student</label><br>
<input type="text" name="student" value='<%=rs.getString("Name")%>' /><br>
</div>
<div class="form-group1">
<label>class score</label>
<input type="text" name="class_score" placeholder="enter class score"/><br>
</div>
<div class="form-group2">
<label>exam score</label>
<input type="text" name="exam_score" placeholder="enter exam score"/>
</div>
</div>
<center> <input style="margin-top:10px;"class="save_btn" type="submit" value="save" /></center>
</form>
<%
}
%>
</div>
</div>
<%
String st_id=request.getParameter("s_id");
String c_score=request.getParameter("class_score");
String e_score=request.getParameter("exam_score");
if(st_id!=null && c_score!=null && e_score!=null){
Basic1_Extension b1e=new Basic1_Extension();
//get grading scheme
double ex,exCal,getClass,getExam,setTotal; String convertExam,grade=null,remark=null;
//fetch scheme
double exam_scheme=0;
try{
String sql2="select exam from score_scheme_table";
pst=con.prepareStatement(sql2);
rs=pst.executeQuery();
if(rs.next()){
exam_scheme=rs.getDouble("exam");
}
}catch(Exception e){
JOptionPane.showMessageDialog(null,e);
}finally{
try{
rs.close();
pst.close();
}
catch(Exception e){
}
}
//convert exam record to scheme value
DecimalFormat df2 = new DecimalFormat(".#");
ex = Double.valueOf(e_score);
exCal = (ex/100)*exam_scheme;
convertExam=String.valueOf(df2.format(exCal));
getExam=Double.valueOf(convertExam);
getClass=Double.valueOf(c_score);
setTotal = getClass + getExam;
//check and initialize grades and remarks
// gr.grade_adaptor(setTotal,grade,remark);
if(setTotal>=80){
grade="A";
remark="ADVANCE";
}else if(setTotal>=75 && setTotal<=79.9){
grade="P";
remark="PROFICIENT";
}else if(setTotal>=70 && setTotal<=74.9){
grade="AP";
remark="APPROACHING PROFICIENT";
}else if(setTotal>=65 && setTotal<=69.9){
grade="D";
remark="DEVELOPING";
}else if(setTotal>=0.0 && setTotal<=64.9){
grade="B";
remark="BEGINNING";
}
//convert total double data type to string
String t_score=String.valueOf(setTotal);
//update student record for subject
try{
String sql1="update class2 set Creative_Arts='"+c_score+"%"+"',Creative_Arts_Exam='"+convertExam+"%"+"',Creative_Arts_Total='"+t_score+"%"+"',Creative_Arts_T='"+t_score+"',Creative_Arts_G='"+grade+"',Creative_Arts_R='"+remark+"' where ID='"+st_id+"'";
pst=con.prepareStatement(sql1);
pst.execute();
b1e.rollnumber();b1e.student_arts_position(); b1e.totalSum();b1e.personal_average();b1e.updateGrandPosition();b1e.class_average();b1e.createComments();
response.sendRedirect("stage2_arts.jsp");
}catch(Exception ep){
JOptionPane.showMessageDialog(null,ep);
}finally{
try{
rs.close();
pst.close();
}
catch(Exception et){
}
}
}
%>
</body>
</html>
please what is the cause of the error message
