java.lang.NullPointerException

[awesemo]

Running the "print-servlet-2.0-SNAPSHOT" on Tomcat 7 for Windows;

I'm getting the following error while executing the sample code "http://localhost:8080/print-servlet-2.0-SNAPSHOT/"

Can someone help me at least identify the cause of the error or guide me for the right configuration.

Thanks;

Error while generating PDF:
java.lang.NullPointerException
    at org.mapfish.print.servlet.MapPrinterServlet.doCreatePDFFile(MapPrinterServlet.java:315)
    at org.mapfish.print.servlet.MapPrinterServlet.createAndGetPDF(MapPrinterServlet.java:155)
    at org.mapfish.print.servlet.MapPrinterServlet.doGet(MapPrinterServlet.java:86)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

[manmorjim]

I got a similar error (NPE) when I tried download a file while mapFish was creating a new one in a concurrent way. Did you get this error in a similar situation?

I created a Jmeter project which has configured two concurrent threads to reproduce the error:

System info:

_OS: GNU/Linux 12.04 x86 3.2.0-69-generic-pae
_Server: Apache tomcat 7.0.39
_Java_: JDK 1.6.0_45