Hi
I need your help again
i was working on a JSP and servlet project on apache tomcat
i got the following error when i start apache server
Apr 26, 2010 6:23:33 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet co_sem_data threw exception
java.lang.NullPointerException
at myPackage.co_sem_data.processRequest(co_sem_data.java:31)
at myPackage.co_sem_data.doGet(co_sem_data.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
at java.lang.Thread.run(Thread.java:619)
Apr 26, 2010 6:35:23 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP:
An error occurred at line: 328 in the jsp file: /co_sem.jsp
The method print(char[]) is ambiguous for the type JspWriter
325:
326: </table>
327: <%} catch(Exception e){e.getMessage();}%>
328: <div align="center"><input type="button" value="jjjj" name="co_sem_data.jsp?id=<%=null%>" onclick = "popUp(this.name);">
329: </div></div>
330:
331: </div>
i don't know why ?
i tried to find the bug but i didn't figure it out
here is the servlet code
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package myPackage;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
protected void processRequest(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
res.setContentType("text/html;charset=UTF-8");
PrintWriter out = res.getWriter();
try {
HttpSession userSession = req.getSession(false);
int id = Integer.parseInt(req.getParameter("id").toString());
String info[] = new String [28];
try{info=DBOP.get_sem_basic_info(id);
}catch (SQLException E) {
out.println("SQLException: " + E.getMessage());
out.println("SQLState: " + E.getSQLState());
out.println("VendorError: " + E.getErrorCode());
}
userSession.putValue("sinfo[1]", info[1]);
userSession.putValue("sinfo[26]",info[26]);
userSession.putValue("semid", id);
System.out.println(id);
RequestDispatcher redirect = getServletContext().getRequestDispatcher("/co_sem_data.jsp");
if (redirect != null) {redirect.forward(req, res);}
} finally {
out.close();
}
}
}
and here is the JSP code
<!--
MAIN CONTENT AREA
-->
<div id="content">
<div id="breadcrumbs">
<a href="co_welcome.jsp">الصفحة الرئيسيه</a> /إدارة البرنامج/
<a href="co_sem.jsp">بيانات تيرم</a>
<br>
</div>
<a name="maincontent" id="maincontent"></a>
<h1>بيانات التيرم</h1>
<p></p>
<%String id ="";%>
<%
try {
PreparedStatement Stmt = null;
DBOP.load_db_driver();
Connection Conn = DBOP.connectToDb();
Stmt = Conn.prepareStatement("SELECT `Sem-record-id`,`Sem-year`,`Sem-term-code` FROM semesterbasicinfo");
Stmt.execute();
ResultSet RS = Stmt.getResultSet();
RS.last();
int rows=RS.getRow();
RS.beforeFirst();
%>
<table border="1" width="100%" style="border-collapse: collapse">
<tr>
<td align="center">
<font color="#FF0000"><b>y</b> </font>
</td>
<td align="center">
<font color="#FF0000"><b>t</b> </font>
</td>
<td align="center">
<font color="#FF0000"><b>ag</b> </font>
</td>
<td align="center">
<font color="#FF0000"><b>pro</b> </font>
</td>
</tr>
<%while (RS.next()) {%>
<%String term=RS.getString(3);term=DBOP.get_Term(term);%>
<tr><%id =RS.getString(1);%>
<td><%=RS.getString(2)%>
</td>
<td><%=term%>
</td>
<td> <a onclick = "popUp(this.name);" name="co_sem_data?id=<%=id%>">ag</a> <-------1------>
</td>
<td><a onclick = "popUp(this.name);" name="co_sem_detail?id=<%=id%>">pro</a> <-------2------->
</td>
</tr>
<%}%>
</table>
<%} catch(Exception e){e.getMessage();} %>
<div align="center"><input type="button" value="add" name="co_sem_data.jsp?id=0" onclick = "popUp(this.name);"> <-----------3-------->
</div></div>
</div>
also i have another problem which is when i click on the button 3 as the first thing i do on the page it works fine, but when i click on link 1 or 2 then i click on the button it does not identify the id well.
can any one hlep
please