How to use solrj with the DismaxRequestHandler?

Question

Due to lack of proper documentation , I am unable to figure out on how to use the dismaxRequestHandler with SolrJ.

On another note , is the standard request handler ,the default in SolrJ's implementation ?

Answer 1

The default="true" in solrconfig.xml decides which is the default request handler. In the examples with solr, the standard request handler is the default.

<requestHandler name="search" class="solr.SearchHandler" default="true">
.....
</requestHandler>

You can easily map this attribute to the other request handlers to make them default.

Example with edismax -

<requestHandler name="/browse" class="solr.SearchHandler" default="true">
 <lst name="defaults">
   <str name="echoParams">explicit</str>
   <str name="defType">edismax</str>
   <str name="q.alt">*:*</str>
   <str name="rows">10</str>
   <str name="fl">*,score</str>
   <str name="qf">
      text^0.5 features^1.0 name^1.2 sku^1.5 id^10.0 manu^1.1 cat^1.4
   </str>
 </lst>
</requestHandler>

The qt parameter can be used with Solrj to query through specific request handler.

Example for Solrj -

CommonsHttpSolrServer commonsHttpSolrServer = new CommonsHttpSolrServer("solr_path_url");
commonsHttpSolrServer.setParser(new XMLResponseParser());
ModifiableSolrParams params = new ModifiableSolrParams();
// Specify the Request handler
params.add("qt", "dismax_request_handler");
params.add("q", "query_string");
QueryResponse response = commonsHttpSolrServer.query(params);