[users@httpd] "java.lang.OutOfMemoryException : Java heap space" for download due to ExtensionsFilter

[Dattaprasad Kamat]

Hi All,
  
 I need help ...
 
 
 I'm using the Tomahawk library in our project. In web.xml I have an entry as follows ...,
 --------------------
     <filter>
   <filter-name>MyFacesExtensionsFilter</filter-name>
   <filter-class>org.apache.myfaces.component.html.util.ExtensionsFilter</filter-class>
     </filter>
    
    
      <filter-mapping>
          <filter-name>MyFacesExtensionsFilter</filter-name>
          <!-- servlet-name must match the name of your javax.faces.webapp.FacesServlet entry -->
          <servlet-name>Faces Servlet</servlet-name>
      </filter-mapping>
      
      <!-- extension mapping for serving page-independent resources (_javascript_, stylesheets, images, etc.)  -->
      <filter-mapping>
          <filter-name>MyFacesExtensionsFilter</filter-name>
          <url-pattern>/faces/myFacesExtensionResource/*</url-pattern>
      </filter-mapping>
         <filter-mapping>
           <filter-name>MyFacesExtensionsFilter</filter-name>
           <url-pattern>*.jsf</url-pattern>
       </filter-mapping> 
         <filter-mapping>
           <filter-name>MyFacesExtensionsFilter</filter-name>
           <url-pattern>*.jsp</url-pattern>
   </filter-mapping> 
  -------------------------
 

 

In the project I have download code as follows :
 
 private void copyFileToResponse(HttpServletResponse response, FileInputStream fileIn) throws IOException {
         int BUFF_SIZE=4096;
   byte[] buffer = new byte[BUFF_SIZE];
   ServletOutputStream responseOutStream = response.getOutputStream();
         BufferedInputStream buf = new BufferedInputStream(fileIn);
         int n = 0;
         int count = 0;
  
  while((n = buf.read (buffer)) != -1) {
 
            
 //            responseOutStream.write(buffer);
             LOGGER.info("while loop : before write to Buffer and count => " + count);
             responseOutStream.write (buffer,0,n);
             count += n;
          
             LOGGER.info("while loop : copyFileToResponse flush");
             responseOutStream.flush();
             LOGGER.info("while loop : copyFileToResponse flushBuffer");
             LOGGER.info("while loop : after buffer read");
         }
         LOGGER.info("after while loop : before flushbuffer");
         buf.close();
         LOGGER.info("after while loop : before flushbuffer");
         response.flushBuffer();
         responseOutStream.close();
         LOGGER.info("after while loop : after flushbuffer");
 }
 
 
 My problem is as follows,
 
 
 If I have the mentioned entries in the web xml and I'm trying to downlaod > 100 MB file,
 
 the above code, throws
 
 "java.lang.OutOfMemoryException : Java heap space"
 
 org.apache.catalina.connector.CoyoteOutputStream.
 
 But it works fine if I remove the entries from the web.xml file.
 
 I have debuuged and found that if I keep above "MyFacesExtensionsFilter" related entries in web.xml, the response is instantiated from org.apache.myfaces.component.html.util.ExtensionsResponseWrapper , in which case flush() doesn't work and causes the "java.lang.OutOfMemoryException : Java heap space" error.
 
 If I remove the MyFacesExtensionsFilter related entries, the response gets instantiated by
 "org.apache.catalina.connector.CoyoteOutputStream", in which case flush works fine.
  
 
 Can anyone tell me how to avoid this situation by still maintaing the "MyFacesExtensionsFilter" related entries in the web.xml.

 

Regards,

Datta