Internal Server Error when indexing a pdf file

[Alessandro Marino]

Hi,
I was trying to use Solr Cell (through the Java API) to index a pdf file.
The class has been extracted from
http://wiki.apache.org/solr/ContentStreamUpdateRequestExample

public class Solr {
  public static void main(String[] args) {
    try {
      String solrId = "beautiful_stm.pdf";
      indexFilesSolrCell(solrId);

    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  public static void indexFilesSolrCell(String solrId)
    throws IOException, SolrServerException {

    String urlString = "http://localhost:8080/solr";;
    SolrServer solr = new CommonsHttpSolrServer(urlString);

    ContentStreamUpdateRequest up = new
ContentStreamUpdateRequest("/update/extract");

    up.addFile(new File("Documents/"+solrId));

    up.setParam("literal.id", solrId);
    up.setParam("uprefix", "attr_");
    up.setParam("fmap.content", "attr_content");

    up.setAction(AbstractUpdateRequest.ACTION.COMMIT, true, true);

    solr.request(up);
  }
}

At runtime I get the exception below:

org.apache.solr.common.SolrException: Internal Server Error

Internal Server Error

request:
http://localhost:8080/solr/update/extract?literal.id=beautiful_stm.pdf&uprefix=attr_&fmap.content=attr_content&commit=true&waitFlush=true&waitSearcher=true&wt=javabin&version=1


What could be the problem? I've tried with various pdf file with different
dimensions but I always get an internal server error.
I've installed Solr (version 1.4) on Tomcat (version 6.0.20) following the
directions at http://wiki.apache.org/solr/SolrTomcat.

Thanks and regards,
Alex