Erro com jasper

Ele gera o arquivo mas nao abre.
Alguem tem alguma ideia?
Obrigado

java.lang.NullPointerException at java.io.ObjectInputStream$PeekInputStream.read(Unknown Source) at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source) at java.io.ObjectInputStream$BlockDataInputStream.readShort(Unknown Source) at java.io.ObjectInputStream.readStreamHeader(Unknown Source) at java.io.ObjectInputStream.<init>(Unknown Source) at net.sf.jasperreports.engine.util.ContextClassLoaderObjectInputStream.<init>(ContextClassLoaderObjectInputStream.java:57) at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:195) at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:607) at exporter.PdfReport.export(PdfReport.java:37) at report.GenericReport.printPdfReport(GenericReport.java:49) at report.GenericReport.generateReport(GenericReport.java:39) at teste.TesteReport.buildReport(TesteReport.java:27) at teste.TesteAction.buildReport(TesteAction.java:34) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.el.parser.AstValue.invoke(AstValue.java:172) at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276) at org.apache.jasper.el.JspMethodExpression.invoke(JspMethodExpression.java:68) at javax.faces.component._MethodExpressionToMethodBinding.invoke(_MethodExpressionToMethodBinding.java:78) at org.apache.myfaces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:57) at javax.faces.component.UICommand.broadcast(UICommand.java:141) at org.ajax4jsf.component.UIInclude.broadcast(UIInclude.java:163) at org.ajax4jsf.component.AjaxViewRoot.processEvents(AjaxViewRoot.java:321) at org.ajax4jsf.component.AjaxViewRoot.broadcastEvents(AjaxViewRoot.java:296) at org.ajax4jsf.component.AjaxViewRoot.processPhase(AjaxViewRoot.java:253) at org.ajax4jsf.component.AjaxViewRoot.processApplication(AjaxViewRoot.java:466) at org.apache.myfaces.lifecycle.InvokeApplicationExecutor.execute(InvokeApplicationExecutor.java:32) at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:103) at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:76) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:151) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:246) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:177) at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:267) at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:380) at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:507) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at filter.SessionFilter.doFilter(SessionFilter.java:42) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:301) 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:286) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) at java.lang.Thread.run(Unknown Source)