Series: ElasticSearch Low Level Rest Client

ElasticSearch: Low Level Rest Client Connection

This entry is part 1 of 3 in the series ElasticSearch Low Level Rest Client

In this tutorial I will show you how to use the ElasticSearch low level rest client.

First you will need to add the low level rest to the pom.

  1. <properties>
  2. 	<elasticSearch.version>6.2.4</elasticSearch.version>
  3. </properties>
  4.  
  5. <dependency>
  6.     <groupId>org.elasticsearch.client</groupId>
  7.     <artifactId>elasticsearch-rest-client</artifactId>
  8.     <version>${elasticSearch.version}</version>
  9. </dependency>

Next you will need to specify the imports.

  1. import org.apache.http.HttpHost;
  2. import org.elasticsearch.client.Response;
  3. import org.elasticsearch.client.RestClient;
  4. import org.elasticsearch.client.RestClientBuilder;

Now you can connect to ElasticSearch.

  1. final RestClientBuilder restClientBuilder = RestClient.builder(new HttpHost("localhost", 9200, "http"));
  2.  
  3. final RestClient restClient = builder.build();

Now you can do whatever you need to!

ElasticSearch: Low Level Client Put

This entry is part 2 of 3 in the series ElasticSearch Low Level Rest Client

In this tutorial I will show you how to put a json document into ElasticSearch. If you have not first connected to ElasticSearch please do so before continuing.

Imports

  1. import org.apache.http.HttpEntity;
  2. import org.apache.http.nio.entity.NStringEntity;
  3. import org.elasticsearch.client.Response;
  4. import org.apache.http.entity.ContentType;
  5. import org.apache.http.util.EntityUtils;

Now perform the PUT request using the low level client.

  1. final String document = "{\"key\": 1 }";
  2. final HttpEntity httpEntity = new NStringEntity(document, ContentType.APPLICATION_JSON);
  3. final Integer id = 1;
  4. final Response response = restClient.performRequest("PUT", "/indexName/indexType/" + id, Collections.<String, String>emptyMap(), httpEntity);
  5.  
  6. //Now you can print the response
  7. System.out.println(EntityUtils.toString(response.getEntity()));

ElasticSearch: Low Level Client Get

This entry is part 3 of 3 in the series ElasticSearch Low Level Rest Client

In this tutorial I will show you how to put a json document into ElasticSearch. If you have not first connected to ElasticSearch please do so before continuing.

POM.xml

  1. <dependency>
  2.     <groupId>com.fasterxml.jackson.core</groupId>
  3.     <artifactId>jackson-databind</artifactId>
  4.     <version>2.9.5</version>
  5. </dependency>

Imports

  1. import org.apache.http.HttpEntity;
  2. import org.apache.http.nio.entity.NStringEntity;
  3. import org.apache.http.entity.ContentType;
  4. import org.elasticsearch.client.Response;
  5. import org.apache.http.util.EntityUtils;

Now perform the GET request using the low level client.

  1. ObjectMapper objectMapper = new ObjectMapper();
  2. final String document = "{\"key\": 1 }";
  3. final JsonNode document = objectMapper.readTree("{" +
  4.    " \"query\": {" +
  5.    " \"match\" : {" +
  6.    " \"key\" : 1 }}}");
  7. final HttpEntity httpEntity = new NStringEntity(document.toString(), ContentType.APPLICATION_JSON);
  8. final Response response = restClient.performRequest("GET", "/indexName/indexType/_search", Collections.<String, String>emptyMap(), httpEntity);
  9.  
  10. //Now you can print the response
  11. System.out.println(EntityUtils.toString(response.getEntity()));
  12.  
  13. //OR get the content
  14. final JsonNode content = objectMapper.readTree(response.getEntity().getContent());
  15. System.out.println(content);