JasperReport error while connecting from Struts action class

[June Rajkhowa]

Hi all,

I am using JasperReport in a Struts-based web application with NetBeans 6.8 and IReport plug-in 3.7.4. I am getting the following error while trying to call the report from action class:
The action class code:

public ActionForward execute(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

         StringWriter stringWriter = new StringWriter();
         PrintWriter printWriter = new PrintWriter(stringWriter);
         ServletOutputStream servletOutputStream = response.getOutputStream();
         InputStream reportStream = getServlet().getServletConfig().getServletContext().getResourceAsStream("SampleReport.jasper");

         try {

            Class.forName("com.mysql.jdbc.Driver").newInstance();
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/SampleDB?user=common&password=common");

            JasperRunManager.runReportToPdfStream(reportStream, servletOutputStream,new HashMap(),connection);

            connection.close();
            response.setContentType("application/pdf");
            response.reset();
            reportStream.close();
            servletOutputStream.flush();
            servletOutputStream.close();

        }  catch (Exception ex) {

            ex.printStackTrace(printWriter);
            response.setContentType("text/plain");
            response.getOutputStream().print(stringWriter.toString());
        }

          return null;
    }

The stack trace of the error is:

java.lang.NullPointerException
at java.io.ObjectInputStream$PeekInputStream.read(ObjectInputStream.java:2266)
at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2279)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:2750)
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:780)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:280)
at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:188)
at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:381)
at net.sf.jasperreports.engine.JasperRunManager.runReportToPdfStream(JasperRunManager.java:186)
at com.bspl.psys.ilp.action.ReportAppLinkAction.execute(ReportAppLinkAction.java:65)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:425)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:228)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:734)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:332)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:233)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57)
at com.sun.grizzly.ContextTask.run(ContextTask.java:69)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309)
at java.lang.Thread.run(Thread.java:619)

I have been coding in Java for some time now but this is the first time I have tried JasperReport. Thanks for any help.

[Girish Wakure]

Hello June!

Can you post actual line numbers along with code in your action file.

there is an some error in line no 65. what dows that line contain? I can not guess the line in above code

[June Rajkhowa]

Hi Girish,

thanks for your reply. The error is in this line:

JasperRunManager.runReportToPdfStream(reportStream, servletOutputStream,new HashMap(), connection);  

The exception is generated here and then the stack trace gets printed.

[Girish Wakure]

Hi again!
Have you checked if any of reportStream, servletOutputStream, connection have null value?

because if there is, then it won't go further.

[June Rajkhowa]

Is Merrill Higginson still around in this forum ?