http://blog.davidvassallo.me/?p=2504

jest_bulk_update_action.java

import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
import io.searchbox.core.Update;
import io.searchbox.core.Bulk;
import io.searchbox.core.Bulk.Builder;
import io.searchbox.action.BulkableAction;
import io.searchbox.client.JestClient;
import io.searchbox.client.JestClientFactory;
import io.searchbox.client.JestResult;
import io.searchbox.client.config.HttpClientConfig;

//initialise objects required to do bulk updates
JestClientFactory factory = new JestClientFactory();
factory.setHttpClientConfig(new HttpClientConfig
                       .Builder("http://"+ElasticSearch_IP+":9200")
                       .multiThreaded(true)
                       .build());
client = factory.getObject();
current_bulkable_action = 0;
bulkProcessor = new Bulk.Builder();

// the below assumes "hit" comes from the ES document you'd like to update
String ES_ID = this.hit.get("_id").getAsString();
String ES_INDEX = this.hit.get("_index").getAsString();
String ES_TYPE = this.hit.get("_type").getAsString();

jsonUpdateObject =  jsonBuilder().startObject().startObject("doc");
jsonUpdateObject
    .field("foo", "bar")
    .field("john", "doe");
    
jsonUpdateObject.endObject().endObject();
update_builder = new Update.Builder(this.jsonUpdateObject.string()).index(ES_INDEX).id(ES_ID).type(ES_TYPE).build());	  

bulkProcessor.addAction(update_builder);
current_bulkable_action += 1;

if (current_bulkable_action > 1000) {
  
  try {
      System.out.println("Flushing BULK processor");
      client.execute(bulkProcessor.build());
      current_bulkable_action = 0;
  } catch (IOException e) {
      e.printStackTrace();
  }
  
  	 
}