Problem with indexing using StreamingUpdateSolrServer in SOLRJ

I just had a miserable failure with SOLRJ. Somehow StreamingUpdateSolrServer failed on some of the items that are being indexed, but others succeeded. It simply throws out an Exception with "Bad Request" message, without any further explanation or stack trace. I suspect that this is due to malformed data, but after double checking, I'm almost sure that they are ok (especially since others are being accepted without problem?).

Can anyone pinpoint any possible reason why this failed miserably? Or do I have a better option in approaching the problem by myself (e.g. different ways of de开发者_如何学Gobugging, etc.)? Thanks much!

2010-10-24 23:49:21,662 {ask-scheduler-5} INFO  [ProductIndexService] Updating product index in batch ...
2010-10-24 23:49:21,851 {ask-scheduler-5} INFO  [ProductIndexService]  Indexing total 28575 products ...
2010-10-24 23:49:22,301 {pool-7-thread-1} INFO  [StreamingUpdateSolrServer] starting runner: org.apache.solr.client.solrj.impl.StreamingUpdateSolrServer$Runner@1dbef987
2010-10-24 23:49:33,287 {pool-7-thread-1} ERROR [StreamingUpdateSolrServer] error
java.lang.Exception: Bad Request

Bad Request

request: http://dev01:8080/solr-gmb/update
 at org.apache.solr.client.solrj.impl.StreamingUpdateSolrServer$Runner.run(StreamingUpdateSolrServer.java:145)
 at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
 at java.lang.Thread.run(Thread.java:619)
2010-10-24 23:49:33,287 {pool-7-thread-1} INFO  [StreamingUpdateSolrServer] finished: org.apache.solr.client.solrj.impl.StreamingUpdateSolrServer$Runner@1dbef987