title: Java jasper report NullPointerException
body: <p>I am new to Java and I am running into this issue that I can't figure out. I inherited this project and I have the following code in one of my scriptlets:</p>
  
  <pre><code>DefaultLogger.logMessage("DEBUG path: "+ reportFile.getPath());
  DefaultLogger.logMessage("DEBUG parameters: "+ parameters);
  DefaultLogger.logMessage("DEBUG jr: "+ jr);
  bytes = JasperRunManager.runReportToPdf(reportFile.getPath(), parameters, jr);
  </code></pre>
  
  <p>And I am getting the following results (the fourth line there is line 287 in FootwearReportsServlet.doGet):</p>
  
  <pre><code>DEBUG path: C:\Development\JavaWorkspaces\Workspace1\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\RSLDevelopmentStandard\reports\templates\footwear\RslFootwearReport.jasper
  DEBUG parameters: {class_list_subreport=net.sf.jasperreports.engine.JasperReport@b07af1, signature_path=images/logo_reports.jpg, submission_id=20070213154168780, test_results_subreport=net.sf.jasperreports.engine.JasperReport@5795ce, logo_path=images/logos_3.gif, report_connection_secondary=com.mysql.jdbc.JDBC4Connection@2c39d2, testing_packages_subreport=net.sf.jasperreports.engine.JasperReport@1883d5f, signature_path2=images/logo_reports.jpg, tpid_subreport=net.sf.jasperreports.engine.JasperReport@17531fd, first_page_subreport=net.sf.jasperreports.engine.JasperReport@12504e0}
  DEBUG jr: net.sf.jasperreports.engine.data.JRMapCollectionDataSource@1630eb6
  Apr 29, 2010 4:15:13 PM org.apache.catalina.core.StandardWrapperValve invoke
  SEVERE: Servlet.service() for servlet FootwearReportsServlet threw exception
  java.lang.NullPointerException
      at net.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:89)
      at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:601)
      at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:517)
      at net.sf.jasperreports.engine.JasperRunManager.runReportToPdf(JasperRunManager.java:385)
      at com.rsl.reports.FootwearReportsServlet.doGet(FootwearReportsServlet.java:287)
      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.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:127)
      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:298)
      at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
      at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
      at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
      at java.lang.Thread.run(Unknown Source)
  </code></pre>
  
  <p>What I can't figure out is where the null reference is. From the debug lines I can see that each parameter has a value. Could it be referring to a bad path to one of the images? Any ideas? For some reason my server won't start in debug mode in Eclipse so I am having trouble figuring this out.</p>