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java.lang.NullPointerException - Cannot Understand Why.

The code below compiles but I keep getting a "java.lang.NullPointerException" error on line 72 at runtime.

Can someone tell me why? This code calls a .jcx (control) file to query a database and return a RowSet.

package Main.pdfGen;
 
import Main.cntrls.*;
import com.bea.wlw.netui.pageflow.Forward;
import com.bea.wlw.netui.pageflow.PageFlowController;
import java.io.*;
 
//iText imports
import com.lowagie.text.*;
import com.lowagie.text.pdf.*;
 
import javax.sql.RowSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import javax.naming.NamingException;
             
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
 
/**
 * @jpf:controller
 * @jpf:view-properties view-properties::
 * <!-- This data is auto-generated. Hand-editing this section is not recommended. -->
 * <view-properties>
 * <pageflow-object id="pageflow:/Main/pdfGen/PdfGenController.jpf"/>
 * <pageflow-object id="action:begin.do">
 *   <property value="80" name="x"/>
 *   <property value="100" name="y"/>
 * </pageflow-object>
 * </view-properties>
 * ::
 */
public class PdfGenController extends PageFlowController
{
    public search searchCNTRL;
    public RowSet pdfRowSet;
 
    /**
     * This method represents the point of entry into the pageflow
     * @jpf:action
     */
    protected Forward begin()throws IOException,SQLException,NamingException
    {   
        HttpServletResponse res;
        HttpServletRequest req;
        ServletOutputStream out;
        res = this.getResponse();
        req = this.getRequest();
        
        res.setContentType("text/HTML");
        out = res.getOutputStream();
        
        String report = req.getParameter("report");
        String dir = req.getParameter("dir");
        String field = req.getParameter("field");
        String value = req.getParameter("value");
        String cnt = req.getParameter("cnt");                                
        
        /*out.print("<html><head></head><body>");
        out.print("Report: " + report + "<br/>");
        out.print("Dir: " + dir + "<br/>");
        out.print("Field: " + field + "<br/>");
        out.print("Value: " + value + "<br/>");
        out.print("Cnt: " + cnt + "<br/>");                                
        out.print("<html><head></head><body>");*/
        
        if(report.equalsIgnoreCase("report_1")){
            // Get DB rows
            pdfRowSet = searchCNTRL.getReportRows(value,"lower(column)","ORDER BY column ASC",0,Integer.parseInt(cnt));  
        }
        
        out.flush();
        out.close();
                
        return null;
    }
}

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ksivananth

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Jonez176

I'm not familiar with the "search" class, but it probably needs to be initialized, which I don't see happening. searchCNTRL is probably a NULL object at line 72 and thus the error occurring. You probably need something along the lines of:

searchCNTRL = new search();

..before you use any methods of searchCNTRL. Hope this works.

ericr29

ASKER

So the code above would be changed to look like this:

public class PdfGenController extends PageFlowController
{
    public search searchCNTRL;
    searchCNTRL = new search();
    public RowSet pdfRowSet;
 
...