ElasticSearch full text search using Java API

Question

I've recently started exploring the world of search, and am trying to use ES as the index for my MongoDB. I've managed to integrate them successfully, but I find the search API rather complex and confusing. The Java API is not too helpful either. I am able to find exact matches, but how do I do full-text searches? Here is my code:

Settings settings = ImmutableSettings.settingsBuilder()
    .put("cluster.name", "elasticsearch").build();
Client client = new TransportClient(settings)
    .addTransportAddress(new InetSocketTransportAddress("host-ip", 9300));
SearchResponse response = client.prepareSearch("mongoindex")
    .setSearchType(SearchType.QUERY_AND_FETCH)
    .setQuery(termQuery("name", "*name*"))
    .setFrom(0).setSize(60).setExplain(true)
    .execute()
    .actionGet();

I have no problems finding "name":"testname" using .setQuery(termQuery("name", "testname")) , but "name":"this is a test name" doesn't work with the above example. What am I doing wrong?

Answer 1

After crawling the Internet for hours, I've managed to figure it out, with some help from the javadocs . The most important is the interface *QueryBuilder* , and its implementing classes. I used FieldQueryBuilder for my query, which in shown in the setQuery method below.

SearchResponse response = client.prepareSearch("mongoindex")
    .setSearchType(SearchType.QUERY_AND_FETCH)
    .setQuery(fieldQuery("name", "test name"))
    .setFrom(0).setSize(60).setExplain(true)
    .execute()
    .actionGet();
SearchHit[] results = response.getHits().getHits();
for (SearchHit hit : results) {
  System.out.println(hit.getId());    //prints out the id of the document
  Map<String,Object> result = hit.getSource();   //the retrieved document
}

With the resulting Map object, you can simply call the get method to retrieve the relevant data.

Answer 2

It looks like termQuery in elasticsearch uses Lucence for it's search syntax. According to the Lucene docs the "*" wildcard is not allowed as the first term of a search.

Answer 3

最好看一下[通配符查询]（ http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/query-dsl-wildcard-query.html ）