Elasticsearch---JAVA RestClient例子说明

elasticsearch 5.0引入了一个新的客户端 RestClient ，使用HTTP API elasticsearch代替内部协议, RestClient 初始化方法是线程安全的，最理想的客户端生命周期是与应用相同，在应用停止服务之前应该关闭客户端链接，释放资源。

    初始化客户端
 

   RestClient restClient = RestClient.builder(
                new HttpHost("xxxx", 9800, "http"),
                new HttpHost("xxxx", 9800, "http")).build();

   关闭客户端连接
   

restClient.close();

RestClient完整示例如下:

package com.fendo.RestClient;
 
import java.io.IOException;
import java.util.Collections;
 
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.nio.client.HttpAsyncClientBuilder;
import org.apache.http.nio.entity.NStringEntity;
import org.apache.http.util.EntityUtils;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Response;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.junit.Before;
import org.junit.Test;
 
/**
 * Elasticserach RestClient示例
 * @author fendo
 *
 */
public class Rest {
    private static RestClient restClient;
    public void getRestClient(){
        
        final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY,
                new UsernamePasswordCredentials("elastic", "changeme"));
        
        restClient = RestClient.builder(new HttpHost("localhost",9200,"http"))
                .setHttpClientConfigCallback(new RestClientBuilder.HttpClientConfigCallback() {
                    @Override
                    public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder) {
                        return httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
                    }
                }).build();
        
    }
    
    @Before
    public void getRest(){
        restClient = RestClient.builder(new HttpHost("localhost", 9200, "http")).build(); 
    }
    
 
 
    /**
     * 查看api信息
     * @throws Exception
     */
    @Test
    public void CatApi() throws Exception{
        String method = "GET";
        String endpoint = "/_cat";
        Response response = restClient.performRequest(method,endpoint);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    /**
     * 创建索引
     * @throws Exception
     */
    @Test
    public void CreateIndex() throws Exception{
        String method = "PUT";
        String endpoint = "/test-index";
        Response response = restClient.performRequest(method,endpoint);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    /**
     * 创建文档
     * @throws Exception
     */
    @Test
    public void CreateDocument()throws Exception{
 
        String method = "PUT";
        String endpoint = "/test-index/test/1";
        HttpEntity entity = new NStringEntity(
                "{\n" +
                        "    \"user\" : \"kimchy\",\n" +
                        "    \"post_date\" : \"2009-11-15T14:12:12\",\n" +
                        "    \"message\" : \"trying out Elasticsearch\"\n" +
                        "}", ContentType.APPLICATION_JSON);
 
        Response response = restClient.performRequest(method,endpoint, Collections.emptyMap(),entity);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    /**
     * 获取文档
     * @throws Exception
     */
    @Test
    public void getDocument()throws Exception{
        String method = "GET";
        String endpoint = "/test-index/test/1";
        Response response = restClient.performRequest(method,endpoint);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    
    /**
     * 查询所有数据
     * @throws Exception
     */
    @Test
    public void QueryAll() throws Exception {
        String method = "POST";
        String endpoint = "/test-index/test/_search";
        HttpEntity entity = new NStringEntity("{\n" +
                "  \"query\": {\n" +
                "    \"match_all\": {}\n" +
                "  }\n" +
                "}", ContentType.APPLICATION_JSON);
 
        Response response = restClient.performRequest(method,endpoint,Collections.emptyMap(),entity);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    /**
     * 根据ID获取
     * @throws Exception
     */
    @Test
    public void QueryByField() throws Exception {
        String method = "POST";
        String endpoint = "/test-index/test/_search";
        HttpEntity entity = new NStringEntity("{\n" +
                "  \"query\": {\n" +
                "    \"match\": {\n" +
                "      \"user\": \"kimchy\"\n" +
                "    }\n" +
                "  }\n" +
                "}", ContentType.APPLICATION_JSON);
 
        Response response = restClient.performRequest(method,endpoint,Collections.emptyMap(),entity);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    /**
     * 更新数据
     * @throws Exception
     */
    @Test
    public void UpdateByScript() throws Exception {
        String method = "POST";
        String endpoint = "/test-index/test/1/_update";
        HttpEntity entity = new NStringEntity("{\n" +
                "  \"doc\": {\n" +
                "    \"user\":\"大美女\"\n" +
                "    }\n" +
                "}", ContentType.APPLICATION_JSON);
        Response response = restClient.performRequest(method,endpoint,Collections.emptyMap(),entity);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
    
    
    @Test
    public void GeoBoundingBox() throws IOException {
        String method = "POST";
        String endpoint = "/attractions/restaurant/_search";
        HttpEntity entity = new NStringEntity("{\n" +
                "  \"query\": {\n" +
                "    \"match_all\": {}\n" +
                "  },\n" +
                "  \"post_filter\": {\n" +
                "    \"geo_bounding_box\": {\n" +
                "      \"location\": {\n" +
                "        \"top_left\": {\n" +
                "          \"lat\": 39.990481,\n" +
                "          \"lon\": 116.277144\n" +
                "        },\n" +
                "        \"bottom_right\": {\n" +
                "          \"lat\": 39.927323,\n" +
                "          \"lon\": 116.405638\n" +
                "        }\n" +
                "      }\n" +
                "    }\n" +
                "  }\n" +
                "}", ContentType.APPLICATION_JSON);
        Response response = restClient.performRequest(method,endpoint,Collections.emptyMap(),entity);
        System.out.println(EntityUtils.toString(response.getEntity()));
    }
}