### Question:
MapReduceSolrInputDocumentWriter implements SolrInputDocumentWriter { @Override public void deleteByQuery(String deleteQuery) throws SolrServerException, IOException { throw new UnsupportedOperationException("Cannot delete records in a MapReduce context"); } MapReduceSolrInputDocumentWriter(Context context); @Override void add(int shard, Map<String, SolrInputDocument> inputDocumentMap); @Override void deleteById(int shard, List<String> idsToDelete); @Override void deleteByQuery(String deleteQuery); @Override void close();  }### Answer:
@Test(expected=UnsupportedOperationException.class) public void testDeleteByQuery() throws SolrServerException, IOException { mrWriter.deleteByQuery("*:*"); }