ElasticSearch Field boosting using java api - search

Question

I am new to ES and trying to search using java apis. I am unable to figure out how I can provide filed specific boosting using the java apis.
Here is the example:
My index document looks like:
_source": {
"th_id": 1,
"th_name": "test name",
"th_description": "test desc",
"th_image": "test-img",
"th_slug": "Make-Me-Smart",
"th_show_title": "Coast Tech Podcast",
"th_sh_category": "Alternative Health
}
When i search for keywords I want to boost the results higher if they found in the "th_name" compared to they're found in some other fields.
Currently I am using below code to do search:
QueryBuilder qb1 = QueryBuilders.multiMatchQuery(keyword, "th_name", "th_description", "th_show_title", "th_sh_category");
SearchResponse response = client.prepareSearch("talk").setTypes("themes")
.setSearchType(SearchType.DFS_QUERY_THEN_FETCH).setQuery(qb1)
.setFrom(start).setSize(maxRows)
.setExplain(true).execute().actionGet();
Is there anything I can do at query time to boost the document if the keyword is found in "th_name" field compared to found in other fields?

Answer 1

The accepted answer did not work me. ES version I am using is 6.2.4.
QueryBuilders.multiMatchQuery(keyword)
.field("th_name" ,2.0f)
.field("th_description")
.field("th_show_title")
.field("content")
Hope it helps someone else.

Answer 2

Edit: This has changed and does no longer work in ES 6.x and upwards.
You should also be able to boost a field directly in the Multi-match query:
"The multi_match query supports field boosting via ^ notation in the fields json field.
{
"multi_match" : {
"query" : "this is a test",
"fields" : [ "subject^2", "message" ]
}
}
In the above example hits in the subject field are 2 times more important than in the message field."
In the java-api, just use the MultiMatchQueryBuilder:
MultiMatchQueryBuilder builder =
new MultiMatchQueryBuilder( keyword, "th_name^2", "th_description", "th_show_title", "th_sh_category" );
Disclaimer: Not tested

Answer 3

You can use "BoostingQuery"
http://www.elasticsearch.org/guide/reference/query-dsl/boosting-query.html
javadoc : https://github.com/elasticsearch/elasticsearch/blob/master/src/main/java/org/elasticsearch/index/query/BoostingQueryBuilder.java