Request is null when Request Wrapper is used in filter

[Ruhul Mazumder]

Hi ALL,

Our application has multipart form and normal form. We are using servlet filter for doing authentication and authorization. For multipart for we are creating request multipart wrapper to do multiple read of multipart data. Everything works fine but sometimes we get null pointer exception while setting attribute in servlets (whenrequest is a multipart wrapper ).

In wrapper we are getting the input stream and storing it in byte array and overring getReader() and getInputStream() to use the byte array

Below is the stack trace,

Jan 13, 2012 10:05:27 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [XXXServlet] in context with path [/XXXX] threw exception
java.lang.NullPointerException
at org.apache.catalina.connector.Request.setAttribute(Request.java:1563)
at org.apache.catalina.connector.RequestFacade.setAttribute(RequestFacade.java:543)
at javax.servlet.ServletRequestWrapper.setAttribute(ServletRequestWrapper.java:239)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:285)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at com.xxx.filter.webfilter.XXXNFilter.doFilter(XXXNFilter.java:78)
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:224)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:304)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)

Please let me know if anyone has face same error and how to solve this issue.

Thanks in Advanced,
Ruhul