use of DataHandler in JavaUtils.convert

[Archit Shah <as...@redhat.com>]

The convert method of org.apache.axis.utils.JavaUtils relies on the 
getContent method of javax.activation.DataHandler to get an InputStream 
for the data, twice doing the following:

    in = (InputStream)handler.getContent();

instead of:

    in = handler.getInputStream();

Calling getContent and casting to InputStream is not guaranteed to work. 
The Javadoc for the getContent method (see [1]) specifies "If no 
DataContentHandler can be found for the the type of this data, the 
DataHandler returns an InputStream for the data." Therefore, the cast 
can fail if a DataContentHandler is installed. I ran into this situation 
using the GNU javamail implementation [2], which has a 
DataContentHandler for the MIME type application/octet-stream. This 
DataContentHandler causes, for certain data, the getContent method to 
return a byte array instead of an InputStream. In particular, I 
encountered a ClassCastException in the JUnit tests 
test.wsdl.interop4.groupG.mime.rpc.MimeRPCInteropTestCase#test2MimeRPCSoapPortEchoAttachments 
and 
test.wsdl.interop4.groupG.dime.rpc.DimeRPCInteropTestCase#test2DimeRPCSoapPortEchoAttachments.

Casting the return value of getContent is also done in another context. 
  JavaUtils and SourceDataHandlerDeserializer both do:

    StreamSource ss = new StreamSource(new StringReader(
      (String) dh.getContent()));

when the following would suffice:

    StreamSource ss = new StreamSource(dh.getInputStream());

Replacing the calls to getContent with calls to getInputStream in these 
  four locations (3 in JavaUtils and 1 in SourceDataHandlerDeserializer) 
  will make Axis more robust to changes in the underlying javamail 
implementations. A patch is attached. The patch produces no regressions 
  in the Axis tests when run with the Sun javamail implementation and 
fixes two test failures encountered when using Axis with the GNU 
javamail implementation

   -- Archit Shah

Links

1. http://java.sun.com/j2ee/1.4/docs/api/javax/activation/DataHandler.html
2. http://www.gnu.org/software/classpathx/javamail/