Elasticsearch mapping settings 'not_analyzed' and grouping by field in Java

Question

I\'m trying to group the results so that they are grouped by category.

SearchResponse response = client.prepareSearch(\"search\")
                .addAggregation         


        

Answer 1

To apply elasticsearch mapping using java api,

STEP 1) First create your mapping for the Elasticsearch type in a json file,

eg. resources/Customer.json

{
    "Customer" : {
                  "settings" : {
                  }, 
                  "properties"   : { 
                    "category" : { "type":"String" , "index" : "not_analyzed"}
                      } 
                   }
              }
      }
}

STEP 2) create a java method to apply mapping from a json file, (see complete example here)

class EsUtils {

  public static Client client

  public static void applyMapping(String index, String type, String location) throws Exception {

            String source = readJsonDefn(location);

            if (source != null) {
                PutMappingRequestBuilder pmrb = client.admin().indices()
                                                      .preparePutMapping(index)
                                                      .setType(type);
                pmrb.setSource(source);
                MappingListener mappingListener = new MappingListener(pmrb)

                // Create type and mapping
                Thread thread = new Thread(mappingListener)

                thread.start();
                while (!mappingListener.processComplete.get()) {
                    System.out.println("not complete yet. Waiting for 100 ms")
                    Thread.sleep(100);

                }

            } else {
                   System.out.println("mapping error");
            }

       }

       public static String readJsonDefn(String url) throws Exception {
                 //implement it the way you like 
              StringBuffer bufferJSON = new StringBuffer();

              FileInputStream input = new FileInputStream(new File(url).absolutePath);
              DataInputStream inputStream = new DataInputStream(input);
              BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));

              String line;

              while ((line = br.readLine()) != null) {
                             bufferJSON.append(line);
              }
              br.close();
              return bufferJSON.toString();
       }
    }

STEP 3) call applyMapping() method passing your es client,

String index = "search"; //yourIndex
String type  = "Customer";
String location = "resources/Customer.json";

EsUtils.client = yourClient; //pass your client
EsUtils.applyMapping(index, type, location);

STEP 4) query as you want,

SearchRequestBuilder builder = client.prepareSearch("search");
builder.addAggregation(AggregationBuilders.terms("categoryterms")
                                          .field("category").size(0))
SearchResponse response = builder.execute().actionGet();

Complete Reference

Elasticsearch apply mapping