title: Posting multipart form data to seam+RESTeasy fails marshalling to InputStream
body: <p>I'm trying to post image data to a seam+RESTeasy endpoint and I'm getting a very cryptic error during JBoss startup.  The HTTP request I'm sending has a content-type of multipart/form-data which has a single image/jpeg part with name "attachment".  My service method looks like this:</p>
  
  <pre><code>@POST
  @Path("uploadSymptomsImage/{appointmentGUID}")
  @Consumes(MediaType.MULTIPART_FORM_DATA)
  @Produces("application/json")
  public String uploadSymptomsImage( @FormParam("attachment") InputStream fileInputStream,
                                     @PathParam("appointmentGUID") String strAppointmentGUID )
  { ...
  </code></pre>
  
  <p>The error that I get is during startup:</p>
  
  <pre><code>Caused by: java.lang.RuntimeException: Unable to find a constructor that takes a String param or a valueOf() or fromString() method for javax.ws.rs.FormParam("attachment") on public java.lang.String com....AppointmentRestService.uploadSymptomsImage(java.io.InputStream,java.lang.String) for basetype: java.io.InputStream
  at org.jboss.resteasy.core.StringParameterInjector.initialize(StringParameterInjector.java:206) [:]
  at org.jboss.resteasy.core.StringParameterInjector.&lt;init&gt;(StringParameterInjector.java:57) [:]
  at org.jboss.resteasy.core.FormParamInjector.&lt;init&gt;(FormParamInjector.java:22) [:]
  </code></pre>
  
  <p>My understanding was that media types could be automatically marshalled to InputStream.  I've also tried java.io.File, java.io.Reader - both with same error.  When I replace with byte[] or String I get a zero length array, or null as the parameter value. </p>
  
  <p>How would you go about debugging this?  Also, is it possible to access the raw request or pre-marshalled values?  </p>
  
  <p>Any suggestions here would be greatly appreciated.  </p>