Elasticsearch应用七：ES Java客户端-Elasticsearch Java client

Myth丶恋晨 2022-02-21 06:02 765阅读 0赞

## 一、ES Client 简介 ##

### 1. ES是一个服务，采用C/S结构 ###

![1227483-20180623183417689-1254706105.png][]

### 2. 回顾 ES的架构 ###

![1227483-20180623183533451-186611934.png][]

### 3. ES支持的客户端连接方式 ###

**3.1 REST API ，端口 9200**

**　　**这种连接方式对应于架构图中的RESTful style API这一层，这种客户端的连接方式是RESTful风格的，使用http的方式进行连接

![1227483-20180623183916238-1857758044.png][]

**3.2 Transport 连接 端口 9300**

这种连接方式对应于架构图中的Transport这一层，这种客户端连接方式是直接连接ES的节点，使用TCP的方式进行连接

![1227483-20180623184101432-1336166083.png][]

### 4. ES提供了多种编程语言客户端 ###

![1227483-20180623184216237-824072141.png][]

官网可以了解详情：

[https://www.elastic.co/guide/en/elasticsearch/client/index.html][https_www.elastic.co_guide_en_elasticsearch_client_index.html]

## 二、Java REST Client介绍 ##

### 1. ES提供了两个JAVA REST client 版本 ###

**Java Low Level REST Client:** 低级别的REST客户端，通过http与集群交互，用户需自己编组请求JSON串，及解析响应JSON串。**兼容所有ES版本**。  
**Java High Level REST Client:** 高级别的REST客户端，基于低级别的REST客户端，增加了编组请求JSON串、解析响应JSON串等相关api。**使用的版本需要保持和ES服务端的版本一致，否则会有版本问题。**

### 2. Java Low Level REST Client 说明 ###

特点，maven 引入、使用介绍： [https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-low.html][https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-low.html]

API doc ：[https://artifacts.elastic.co/javadoc/org/elasticsearch/client/elasticsearch-rest-client/6.2.4/index.html.][https_artifacts.elastic.co_javadoc_org_elasticsearch_client_elasticsearch-rest-client_6.2.4_index.html.]

### 3. Java High Level REST Client 说明 ###

从6.0.0开始加入的，目的是以java面向对象的方式来进行请求、响应处理。  
每个API 支持 同步/异步 两种方式，同步方法直接返回一个结果对象。**异步的方法以async为后缀，通过listener参数来通知结果**。  
高级java REST 客户端依赖Elasticsearch core project

兼容性说明：

依赖 java1.8 和 Elasticsearch core project  
**请使用与服务端ES版本一致的客户端版本**

### 4. Java High Level REST Client  maven 集成 ###

<dependency>
 <groupId>org.elasticsearch.client</groupId>
 <artifactId>elasticsearch-rest-high-level-client</artifactId>
 <version>6.2.4</version>
 </dependency>

### 5. Java High Level REST Client  初始化 ###

RestHighLevelClient client = new RestHighLevelClient(
            RestClient.builder(
                    new HttpHost("localhost", 9200, "http"),
                    new HttpHost("localhost", 9201, "http")));

给定集群的多个节点地址，将客户端负载均衡地向这个节点地址集发请求

Client 不再使用了，记得关闭它：

client.close();

API及用法示例，请参考：

[https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-supported-apis.html][https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-supported-apis.html]

## 三、Java High Level REST Client  使用示例 ##

准备：

**编写示例之前首先在maven工程里面引入和ES服务端版本一样的Java客户端**

<dependency>
 <groupId>org.elasticsearch.client</groupId>
 <artifactId>elasticsearch-rest-high-level-client</artifactId>
 <version>6.2.4</version>
 </dependency>

给定集群的多个节点地址，将客户端负载均衡地向这个节点地址集发请求：

InitDemo.java

package com.study.es_hrset_client;
    
    import org.apache.http.HttpHost;
    import org.elasticsearch.client.RestClient;
    import org.elasticsearch.client.RestHighLevelClient;
    
    /**
     * 
     * @Description: 获取Java High Level REST Client客户端
     * @author lgs
     * @date 2018年6月23日
     *
     */
    public class InitDemo {
    
        public static RestHighLevelClient getClient() {
    
            RestHighLevelClient client = new RestHighLevelClient(
                    RestClient.builder(new HttpHost("localhost", 9200, "http"),
                            new HttpHost("localhost", 9201, "http")));
    
            return client;
        }
    }

### 注意使用ES的客户端时类比之前我们在Kibana进行的ES的相关操作，这样使用起来更加有效果 ###

![1227483-20180623191506381-1909949862.png][]

### 1. Create index 创建索引 ###

CreateIndexDemo.java

package com.study.es_hrset_client;
 
 import java.io.IOException;
 
 import org.elasticsearch.action.admin.indices.alias.Alias;
 import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
 import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
 import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentType;
 
 /**
 * 
 * @Description: 创建索引
 * @author lgs
 * @date 2018年6月23日
 *
 */
 public class CreateIndexDemo {
 
 public static void main(String[] args) {
 try (RestHighLevelClient client = InitDemo.getClient();) {
 
 // 1、创建 创建索引request 参数：索引名mess
 CreateIndexRequest request = new CreateIndexRequest("mess");
 
 // 2、设置索引的settings
 request.settings(Settings.builder().put("index.number_of_shards", 3) // 分片数
 .put("index.number_of_replicas", 2) // 副本数
 .put("analysis.analyzer.default.tokenizer", "ik_smart") // 默认分词器
 );
 
 // 3、设置索引的mappings
 request.mapping("_doc",
 " {\n" +
 " \"_doc\": {\n" +
 " \"properties\": {\n" +
 " \"message\": {\n" +
 " \"type\": \"text\"\n" +
 " }\n" +
 " }\n" +
 " }\n" +
 " }",
 XContentType.JSON);
 
 // 4、 设置索引的别名
 request.alias(new Alias("mmm"));
 
 // 5、 发送请求
 // 5.1 同步方式发送请求
 CreateIndexResponse createIndexResponse = client.indices()
 .create(request);
 
 // 6、处理响应
 boolean acknowledged = createIndexResponse.isAcknowledged();
 boolean shardsAcknowledged = createIndexResponse
 .isShardsAcknowledged();
 System.out.println("acknowledged = " + acknowledged);
 System.out.println("shardsAcknowledged = " + shardsAcknowledged);
 
 // 5.1 异步方式发送请求
 /*ActionListener<CreateIndexResponse> listener = new ActionListener<CreateIndexResponse>() {
 @Override
 public void onResponse(
 CreateIndexResponse createIndexResponse) {
 // 6、处理响应
 boolean acknowledged = createIndexResponse.isAcknowledged();
 boolean shardsAcknowledged = createIndexResponse
 .isShardsAcknowledged();
 System.out.println("acknowledged = " + acknowledged);
 System.out.println(
 "shardsAcknowledged = " + shardsAcknowledged);
 }
 
 @Override
 public void onFailure(Exception e) {
 System.out.println("创建索引异常：" + e.getMessage());
 }
 };
 
 client.indices().createAsync(request, listener);
 */
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

运行结果：

acknowledged = true
    shardsAcknowledged = true

### 2. index  document ###

索引文档，即往索引里面放入文档数据.类似于数据库里面向表里面插入一行数据，一行数据就是一个文档

IndexDocumentDemo.java

package com.study.es_hrset_client;
 
 import java.io.IOException;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.DocWriteResponse;
 import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.index.IndexResponse;
 import org.elasticsearch.action.support.replication.ReplicationResponse;
 import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.rest.RestStatus;
 
 /**
 * 
 * @Description: 索引文档，即往索引里面放入文档数据.类似于数据库里面向表里面插入一行数据，一行数据就是一个文档
 * @author lgs
 * @date 2018年6月23日
 *
 */
 public class IndexDocumentDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (RestHighLevelClient client = InitDemo.getClient();) {
 // 1、创建索引请求
 IndexRequest request = new IndexRequest(
 "mess", //索引
 "_doc", // mapping type
 "1"); //文档id 
 
 // 2、准备文档数据
 // 方式一：直接给JSON串
 String jsonString = "{" +
 "\"user\":\"kimchy\"," +
 "\"postDate\":\"2013-01-30\"," +
 "\"message\":\"trying out Elasticsearch\"" +
 "}";
 request.source(jsonString, XContentType.JSON); 
 
 // 方式二：以map对象来表示文档
 /*
 Map<String, Object> jsonMap = new HashMap<>();
 jsonMap.put("user", "kimchy");
 jsonMap.put("postDate", new Date());
 jsonMap.put("message", "trying out Elasticsearch");
 request.source(jsonMap); 
 */
 
 // 方式三：用XContentBuilder来构建文档
 /*
 XContentBuilder builder = XContentFactory.jsonBuilder();
 builder.startObject();
 {
 builder.field("user", "kimchy");
 builder.field("postDate", new Date());
 builder.field("message", "trying out Elasticsearch");
 }
 builder.endObject();
 request.source(builder); 
 */
 
 // 方式四：直接用key-value对给出
 /*
 request.source("user", "kimchy",
 "postDate", new Date(),
 "message", "trying out Elasticsearch");
 */
 
 //3、其他的一些可选设置
 /*
 request.routing("routing"); //设置routing值
 request.timeout(TimeValue.timeValueSeconds(1)); //设置主分片等待时长
 request.setRefreshPolicy("wait_for"); //设置重刷新策略
 request.version(2); //设置版本号
 request.opType(DocWriteRequest.OpType.CREATE); //操作类别 
 */
 
 //4、发送请求
 IndexResponse indexResponse = null;
 try {
 // 同步方式
 indexResponse = client.index(request); 
 } catch(ElasticsearchException e) {
 // 捕获，并处理异常
 //判断是否版本冲突、create但文档已存在冲突
 if (e.status() == RestStatus.CONFLICT) {
 logger.error("冲突了，请在此写冲突处理逻辑！\n" + e.getDetailedMessage());
 }
 
 logger.error("索引异常", e);
 }
 
 //5、处理响应
 if(indexResponse != null) {
 String index = indexResponse.getIndex();
 String type = indexResponse.getType();
 String id = indexResponse.getId();
 long version = indexResponse.getVersion();
 if (indexResponse.getResult() == DocWriteResponse.Result.CREATED) {
 System.out.println("新增文档成功，处理逻辑代码写到这里。");
 } else if (indexResponse.getResult() == DocWriteResponse.Result.UPDATED) {
 System.out.println("修改文档成功，处理逻辑代码写到这里。");
 }
 // 分片处理信息
 ReplicationResponse.ShardInfo shardInfo = indexResponse.getShardInfo();
 if (shardInfo.getTotal() != shardInfo.getSuccessful()) {
 
 }
 // 如果有分片副本失败，可以获得失败原因信息
 if (shardInfo.getFailed() > 0) {
 for (ReplicationResponse.ShardInfo.Failure failure : shardInfo.getFailures()) {
 String reason = failure.reason(); 
 System.out.println("副本失败原因：" + reason);
 }
 }
 }
 
 
 //异步方式发送索引请求
 /*ActionListener<IndexResponse> listener = new ActionListener<IndexResponse>() {
 @Override
 public void onResponse(IndexResponse indexResponse) {
 
 }
 
 @Override
 public void onFailure(Exception e) {
 
 }
 };
 client.indexAsync(request, listener);
 */
 
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

运行结果：

新增文档成功，处理逻辑代码写到这里。

### 3. get  document ###

获取文档数据

GetDocumentDemo.java

package com.study.es_hrset_client;
 
 import java.io.IOException;
 import java.util.Map;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.fetch.subphase.FetchSourceContext;
 
 /**
 * 
 * @Description: 获取文档数据
 * @author lgs
 * @date 2018年6月23日
 *
 */
 public class GetDocumentDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (RestHighLevelClient client = InitDemo.getClient();) {
 // 1、创建获取文档请求
 GetRequest request = new GetRequest(
 "mess", //索引
 "_doc", // mapping type
 "1"); //文档id 
 
 // 2、可选的设置
 //request.routing("routing");
 //request.version(2);
 
 //request.fetchSourceContext(new FetchSourceContext(false)); //是否获取_source字段
 //选择返回的字段
 String[] includes = new String[]{"message", "*Date"};
 String[] excludes = Strings.EMPTY_ARRAY;
 FetchSourceContext fetchSourceContext = new FetchSourceContext(true, includes, excludes);
 request.fetchSourceContext(fetchSourceContext); 
 
 //也可写成这样
 /*String[] includes = Strings.EMPTY_ARRAY;
 String[] excludes = new String[]{"message"};
 FetchSourceContext fetchSourceContext = new FetchSourceContext(true, includes, excludes);
 request.fetchSourceContext(fetchSourceContext);*/
 
 
 // 取stored字段
 /*request.storedFields("message"); 
 GetResponse getResponse = client.get(request);
 String message = getResponse.getField("message").getValue();*/
 
 
 //3、发送请求 
 GetResponse getResponse = null;
 try {
 // 同步请求
 getResponse = client.get(request);
 } catch (ElasticsearchException e) {
 if (e.status() == RestStatus.NOT_FOUND) {
 logger.error("没有找到该id的文档" );
 }
 if (e.status() == RestStatus.CONFLICT) {
 logger.error("获取时版本冲突了，请在此写冲突处理逻辑！" );
 }
 logger.error("获取文档异常", e);
 }
 
 //4、处理响应
 if(getResponse != null) {
 String index = getResponse.getIndex();
 String type = getResponse.getType();
 String id = getResponse.getId();
 if (getResponse.isExists()) { // 文档存在
 long version = getResponse.getVersion();
 String sourceAsString = getResponse.getSourceAsString(); //结果取成 String 
 Map<String, Object> sourceAsMap = getResponse.getSourceAsMap(); // 结果取成Map
 byte[] sourceAsBytes = getResponse.getSourceAsBytes(); //结果取成字节数组
 
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info(sourceAsString);
 
 } else {
 logger.error("没有找到该id的文档" );
 }
 }
 
 
 //异步方式发送获取文档请求
 /*
 ActionListener<GetResponse> listener = new ActionListener<GetResponse>() {
 @Override
 public void onResponse(GetResponse getResponse) {
 
 }
 
 @Override
 public void onFailure(Exception e) {
 
 }
 };
 client.getAsync(request, listener);
 */
 
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

###  4. Bulk  ###

批量索引文档，即批量往索引里面放入文档数据.类似于数据库里面批量向表里面插入多行数据，一行数据就是一个文档

BulkDemo.java

###  5. search ###

搜索数据

SearchDemo.java

package com.study.es_hrset_client;
 
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.action.search.ShardSearchFailure;
 import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.elasticsearch.search.suggest.Suggest;
 import org.elasticsearch.search.suggest.term.TermSuggestion;
 
 /**
 * 
 * @Description: 搜索数据
 * @author lgs
 * @date 2018年6月23日
 *
 */
 public class SearchDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (RestHighLevelClient client = InitDemo.getClient();) {
 
 // 1、创建search请求
 //SearchRequest searchRequest = new SearchRequest();
 SearchRequest searchRequest = new SearchRequest("bank"); 
 searchRequest.types("_doc");
 
 // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
 SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
 
 //构造QueryBuilder
 /*QueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("user", "kimchy")
 .fuzziness(Fuzziness.AUTO)
 .prefixLength(3)
 .maxExpansions(10);
 sourceBuilder.query(matchQueryBuilder);*/
 
 sourceBuilder.query(QueryBuilders.termQuery("age", 24)); 
 sourceBuilder.from(0); 
 sourceBuilder.size(10); 
 sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS)); 
 
 //是否返回_source字段
 //sourceBuilder.fetchSource(false);
 
 //设置返回哪些字段
 /*String[] includeFields = new String[] {"title", "user", "innerObject.*"};
 String[] excludeFields = new String[] {"_type"};
 sourceBuilder.fetchSource(includeFields, excludeFields);*/
 
 //指定排序
 //sourceBuilder.sort(new ScoreSortBuilder().order(SortOrder.DESC)); 
 //sourceBuilder.sort(new FieldSortBuilder("_uid").order(SortOrder.ASC));
 
 // 设置返回 profile 
 //sourceBuilder.profile(true);
 
 //将请求体加入到请求中
 searchRequest.source(sourceBuilder);
 
 // 可选的设置
 //searchRequest.routing("routing");
 
 // 高亮设置
 /*
 HighlightBuilder highlightBuilder = new HighlightBuilder(); 
 HighlightBuilder.Field highlightTitle =
 new HighlightBuilder.Field("title"); 
 highlightTitle.highlighterType("unified"); 
 highlightBuilder.field(highlightTitle); 
 HighlightBuilder.Field highlightUser = new HighlightBuilder.Field("user");
 highlightBuilder.field(highlightUser);
 sourceBuilder.highlighter(highlightBuilder);*/
 
 
 //加入聚合
 /*TermsAggregationBuilder aggregation = AggregationBuilders.terms("by_company")
 .field("company.keyword");
 aggregation.subAggregation(AggregationBuilders.avg("average_age")
 .field("age"));
 sourceBuilder.aggregation(aggregation);*/
 
 //做查询建议
 /*SuggestionBuilder termSuggestionBuilder =
 SuggestBuilders.termSuggestion("user").text("kmichy"); 
 SuggestBuilder suggestBuilder = new SuggestBuilder();
 suggestBuilder.addSuggestion("suggest_user", termSuggestionBuilder); 
 sourceBuilder.suggest(suggestBuilder);*/
 
 //3、发送请求 
 SearchResponse searchResponse = client.search(searchRequest);
 
 
 //4、处理响应
 //搜索结果状态信息
 RestStatus status = searchResponse.status();
 TimeValue took = searchResponse.getTook();
 Boolean terminatedEarly = searchResponse.isTerminatedEarly();
 boolean timedOut = searchResponse.isTimedOut();
 
 //分片搜索情况
 int totalShards = searchResponse.getTotalShards();
 int successfulShards = searchResponse.getSuccessfulShards();
 int failedShards = searchResponse.getFailedShards();
 for (ShardSearchFailure failure : searchResponse.getShardFailures()) {
 // failures should be handled here
 }
 
 //处理搜索命中文档结果
 SearchHits hits = searchResponse.getHits();
 
 long totalHits = hits.getTotalHits();
 float maxScore = hits.getMaxScore();
 
 SearchHit[] searchHits = hits.getHits();
 for (SearchHit hit : searchHits) {
 // do something with the SearchHit
 
 String index = hit.getIndex();
 String type = hit.getType();
 String id = hit.getId();
 float score = hit.getScore();
 
 //取_source字段值
 String sourceAsString = hit.getSourceAsString(); //取成json串
 Map<String, Object> sourceAsMap = hit.getSourceAsMap(); // 取成map对象
 //从map中取字段值
 /*
 String documentTitle = (String) sourceAsMap.get("title"); 
 List<Object> users = (List<Object>) sourceAsMap.get("user");
 Map<String, Object> innerObject = (Map<String, Object>) sourceAsMap.get("innerObject");
 */
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info(sourceAsString);
 
 //取高亮结果
 /*Map<String, HighlightField> highlightFields = hit.getHighlightFields();
 HighlightField highlight = highlightFields.get("title"); 
 Text[] fragments = highlight.fragments(); 
 String fragmentString = fragments[0].string();*/
 }
 
 // 获取聚合结果
 /*
 Aggregations aggregations = searchResponse.getAggregations();
 Terms byCompanyAggregation = aggregations.get("by_company"); 
 Bucket elasticBucket = byCompanyAggregation.getBucketByKey("Elastic"); 
 Avg averageAge = elasticBucket.getAggregations().get("average_age"); 
 double avg = averageAge.getValue();
 */
 
 // 获取建议结果
 /*Suggest suggest = searchResponse.getSuggest(); 
 TermSuggestion termSuggestion = suggest.getSuggestion("suggest_user"); 
 for (TermSuggestion.Entry entry : termSuggestion.getEntries()) { 
 for (TermSuggestion.Entry.Option option : entry) { 
 String suggestText = option.getText().string();
 }
 }
 */
 
 //异步方式发送获查询请求
 /*
 ActionListener<SearchResponse> listener = new ActionListener<SearchResponse>() {
 @Override
 public void onResponse(SearchResponse getResponse) {
 //结果获取
 }
 
 @Override
 public void onFailure(Exception e) {
 //失败处理
 }
 };
 client.searchAsync(searchRequest, listener); 
 */
 
 } catch (IOException e) {
 logger.error(e);
 }
 }
 }

###  6. highlight 高亮 ###

HighlightDemo.java

package com.study.es_hrset_client;
 
 import java.io.IOException;
 import java.util.Map;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.text.Text;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
 
 /**
 * 
 * @Description: 高亮
 * @author lgs
 * @date 2018年6月23日
 *
 */
 public class HighlightDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (RestHighLevelClient client = InitDemo.getClient();) {
 
 // 1、创建search请求
 SearchRequest searchRequest = new SearchRequest("hl_test"); 
 
 // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
 SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
 
 //构造QueryBuilder
 QueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("title", "lucene solr");
 sourceBuilder.query(matchQueryBuilder);
 
 //分页设置
 /*sourceBuilder.from(0); 
 sourceBuilder.size(5); ;*/ 
 
 
 // 高亮设置
 HighlightBuilder highlightBuilder = new HighlightBuilder(); 
 highlightBuilder.requireFieldMatch(false).field("title").field("content")
 .preTags("").postTags("");
 //不同字段可有不同设置，如不同标签
 /*HighlightBuilder.Field highlightTitle = new HighlightBuilder.Field("title"); 
 highlightTitle.preTags("").postTags("");
 highlightBuilder.field(highlightTitle); 
 HighlightBuilder.Field highlightContent = new HighlightBuilder.Field("content");
 highlightContent.preTags("").postTags("");
 highlightBuilder.field(highlightContent).requireFieldMatch(false);*/
 
 sourceBuilder.highlighter(highlightBuilder);
 
 searchRequest.source(sourceBuilder);
 
 //3、发送请求 
 SearchResponse searchResponse = client.search(searchRequest);
 
 
 //4、处理响应
 if(RestStatus.OK.equals(searchResponse.status())) {
 //处理搜索命中文档结果
 SearchHits hits = searchResponse.getHits();
 long totalHits = hits.getTotalHits();
 
 SearchHit[] searchHits = hits.getHits();
 for (SearchHit hit : searchHits) { 
 String index = hit.getIndex();
 String type = hit.getType();
 String id = hit.getId();
 float score = hit.getScore();
 
 //取_source字段值
 //String sourceAsString = hit.getSourceAsString(); //取成json串
 Map<String, Object> sourceAsMap = hit.getSourceAsMap(); // 取成map对象
 //从map中取字段值
 /*String title = (String) sourceAsMap.get("title"); 
 String content = (String) sourceAsMap.get("content"); */
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info("sourceMap : " + sourceAsMap);
 //取高亮结果
 Map<String, HighlightField> highlightFields = hit.getHighlightFields();
 HighlightField highlight = highlightFields.get("title"); 
 if(highlight != null) {
 Text[] fragments = highlight.fragments(); //多值的字段会有多个值
 if(fragments != null) {
 String fragmentString = fragments[0].string();
 logger.info("title highlight : " + fragmentString);
 //可用高亮字符串替换上面sourceAsMap中的对应字段返回到上一级调用
 //sourceAsMap.put("title", fragmentString);
 }
 }
 
 highlight = highlightFields.get("content"); 
 if(highlight != null) {
 Text[] fragments = highlight.fragments(); //多值的字段会有多个值
 if(fragments != null) {
 String fragmentString = fragments[0].string();
 logger.info("content highlight : " + fragmentString);
 //可用高亮字符串替换上面sourceAsMap中的对应字段返回到上一级调用
 //sourceAsMap.put("content", fragmentString);
 }
 }
 }
 }
 
 } catch (IOException e) {
 logger.error(e);
 }
 }
 }

###  7. suggest 查询建议 ###

SuggestDemo.java

package com.study.es_hrset_client;
    
    import java.io.IOException;
    
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.Logger;
    import org.elasticsearch.action.search.SearchRequest;
    import org.elasticsearch.action.search.SearchResponse;
    import org.elasticsearch.client.RestHighLevelClient;
    import org.elasticsearch.rest.RestStatus;
    import org.elasticsearch.search.builder.SearchSourceBuilder;
    import org.elasticsearch.search.suggest.Suggest;
    import org.elasticsearch.search.suggest.SuggestBuilder;
    import org.elasticsearch.search.suggest.SuggestBuilders;
    import org.elasticsearch.search.suggest.SuggestionBuilder;
    import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
    import org.elasticsearch.search.suggest.term.TermSuggestion;
    
    /**
     * 
     * @Description: 查询建议
     * @author lgs
     * @date 2018年6月23日
     *
     */
    public class SuggestDemo {
        
        private static Logger logger = LogManager.getRootLogger();  
        
        //词项建议拼写检查，检查用户的拼写是否错误，如果有错给用户推荐正确的词，appel->apple
        public static void termSuggest() {
            try (RestHighLevelClient client = InitDemo.getClient();) {
                
                // 1、创建search请求
                //SearchRequest searchRequest = new SearchRequest();
                SearchRequest searchRequest = new SearchRequest("mess"); 
                
                // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
                SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
                 
                sourceBuilder.size(0); 
                
                //做查询建议        
                //词项建议
                SuggestionBuilder termSuggestionBuilder =
                        SuggestBuilders.termSuggestion("user").text("kmichy"); 
                SuggestBuilder suggestBuilder = new SuggestBuilder();
                suggestBuilder.addSuggestion("suggest_user", termSuggestionBuilder);     
                sourceBuilder.suggest(suggestBuilder);
                
                searchRequest.source(sourceBuilder);    
                
                //3、发送请求        
                SearchResponse searchResponse = client.search(searchRequest);
                
                
                //4、处理响应
                //搜索结果状态信息
                if(RestStatus.OK.equals(searchResponse.status())) {
                    // 获取建议结果
                    Suggest suggest = searchResponse.getSuggest(); 
                    TermSuggestion termSuggestion = suggest.getSuggestion("suggest_user"); 
                    for (TermSuggestion.Entry entry : termSuggestion.getEntries()) { 
                        logger.info("text: " + entry.getText().string());
                        for (TermSuggestion.Entry.Option option : entry) { 
                            String suggestText = option.getText().string();
                            logger.info("   suggest option : " + suggestText);
                        }
                    }
                }
                /*
                  "suggest": {
                    "my-suggestion": [
                      {
                        "text": "tring",
                        "offset": 0,
                        "length": 5,
                        "options": [
                          {
                            "text": "trying",
                            "score": 0.8,
                            "freq": 1
                          }
                        ]
                      },
                      {
                        "text": "out",
                        "offset": 6,
                        "length": 3,
                        "options": []
                      },
                      {
                        "text": "elasticsearch",
                        "offset": 10,
                        "length": 13,
                        "options": []
                      }
                    ]
                  }*/
    
            } catch (IOException e) {
                logger.error(e);
            }
        }
        
        //自动补全，根据用户的输入联想到可能的词或者短语
        public static void completionSuggester() {
            try (RestHighLevelClient client = InitDemo.getClient();) {
                
                // 1、创建search请求
                //SearchRequest searchRequest = new SearchRequest();
                SearchRequest searchRequest = new SearchRequest("music"); 
                
                // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
                SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
                 
                sourceBuilder.size(0); 
                
                //做查询建议        
                //自动补全
                /*POST music/_search?pretty
                        {
                            "suggest": {
                                "song-suggest" : {
                                    "prefix" : "lucene s", 
                                    "completion" : { 
                                        "field" : "suggest" ,
                                        "skip_duplicates": true
                                    }
                                }
                            }
                        }*/
    
                SuggestionBuilder termSuggestionBuilder =
                        SuggestBuilders.completionSuggestion("suggest").prefix("lucene s")
                        .skipDuplicates(true); 
                SuggestBuilder suggestBuilder = new SuggestBuilder();
                suggestBuilder.addSuggestion("song-suggest", termSuggestionBuilder);     
                sourceBuilder.suggest(suggestBuilder);
                
                searchRequest.source(sourceBuilder);    
                
                //3、发送请求        
                SearchResponse searchResponse = client.search(searchRequest);
                
                
                //4、处理响应
                //搜索结果状态信息
                if(RestStatus.OK.equals(searchResponse.status())) {
                    // 获取建议结果
                    Suggest suggest = searchResponse.getSuggest(); 
                    CompletionSuggestion termSuggestion = suggest.getSuggestion("song-suggest"); 
                    for (CompletionSuggestion.Entry entry : termSuggestion.getEntries()) { 
                        logger.info("text: " + entry.getText().string());
                        for (CompletionSuggestion.Entry.Option option : entry) { 
                            String suggestText = option.getText().string();
                            logger.info("   suggest option : " + suggestText);
                        }
                    }
                }
    
            } catch (IOException e) {
                logger.error(e);
            }
        }
    
        public static void main(String[] args) {
            termSuggest();
            
            logger.info("--------------------------------------");
            
            completionSuggester();
        }
    }

###  8. aggregation 聚合分析 ###

AggregationDemo.java

###  9. 官网资料 ###

各种查询对应的QueryBuilder：

[https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-query-builders.html][https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-query-builders.html]

各种聚合对应的AggregationBuilder：

[https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-aggregation-builders.html][https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-aggregation-builders.html]

## 四、Java Client ##

### 1. Java Client 说明 ###

java client 使用 TransportClient，各种操作本质上都是异步的(可以用 listener，或返回 Future ）。   
注意：ES的发展规划中在7.0版本开始将废弃 TransportClient，8.0版本中将完全移除 TransportClient，取而代之的是High Level REST Client。  
High Level REST Client 中的操作API和java client 大多是一样的。

### 2. 官方学习链接 ###

[https://www.elastic.co/guide/en/elasticsearch/client/java-api/current/index.html][https_www.elastic.co_guide_en_elasticsearch_client_java-api_current_index.html]

### 3. 兼容性说明 ###

请使用与服务端ES版本一致的客户端版本

### 4. Java Client maven 集成 ###

<dependency>
 <groupId>org.elasticsearch.client</groupId>
 <artifactId>transport</artifactId>
 <version>6.2.4</version>
 </dependency>

### 5. Java Client logger 日志器说明 ###

使用的是 log4j2 日志组件。  
如果要使用其他的日志组件，可使用slf4j作桥

### 6. Init Client ###

![1227483-20180623201145595-1312856554.png][]

**Init Client setting 可用参数说明：**

**cluster.name**  
指定集群的名字，如果集群的名字不是默认的elasticsearch，需指定。  
**client.transport.sniff**  
设置为true,将自动嗅探整个集群，自动加入集群的节点到连接列表中。  
**client.transport.ignore\_cluster\_name**  
Set to true to ignore cluster name validation of connected nodes. (since 0.19.4)  
**client.transport.ping\_timeout**  
The time to wait for a ping response from a node. Defaults to 5s.  
**client.transport.nodes\_sampler\_interval**  
How often to sample / ping the nodes listed and connected. Defaults to 5s.

## 五、Java Client使用示例 ##

**注意：TransPort客户端的使用和RESTful风格的使用基本一致，除了获取客户端不一样，还有发送请求有的不一样外**

准备：

**编写示例之前首先在maven工程里面引入和ES服务端版本一样的Java客户端**

<dependency>
 <groupId>org.elasticsearch.client</groupId>
 <artifactId>transport</artifactId>
 <version>6.2.4</version>
 </dependency>

给定集群的多个节点地址，将客户端负载均衡地向这个节点地址集发请求：

InitDemo.java

package com.study.es_java_client;
    
    import java.net.InetAddress;
    import java.net.UnknownHostException;
    
    import org.elasticsearch.client.transport.TransportClient;
    import org.elasticsearch.common.settings.Settings;
    import org.elasticsearch.common.transport.TransportAddress;
    import org.elasticsearch.transport.client.PreBuiltTransportClient;
    
    public class InitDemo {
        
        private static TransportClient client;
    
        public static TransportClient getClient() throws UnknownHostException {
    
            if(client == null) {
                //client = new PreBuiltTransportClient(Settings.EMPTY)
                
                // 连接集群的设置
                Settings settings = Settings.builder()
                        //.put("cluster.name", "myClusterName") //如果集群的名字不是默认的elasticsearch，需指定
                        .put("client.transport.sniff", true) //自动嗅探
                        .build();   
                client = new PreBuiltTransportClient(settings)
                    //.addTransportAddress(new TransportAddress(InetAddress.getByName("localhost"), 9300));
                    .addTransportAddress(new TransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
                
                //可用连接设置参数说明
                /*
                cluster.name
                    指定集群的名字，如果集群的名字不是默认的elasticsearch，需指定。
                client.transport.sniff
                    设置为true,将自动嗅探整个集群，自动加入集群的节点到连接列表中。    
                client.transport.ignore_cluster_name
                    Set to true to ignore cluster name validation of connected nodes. (since 0.19.4)    
                client.transport.ping_timeout
                    The time to wait for a ping response from a node. Defaults to 5s.
                client.transport.nodes_sampler_interval
                    How often to sample / ping the nodes listed and connected. Defaults to 5s.
                */
                
            }
            return client;
        }
    }

### 注意使用ES的客户端时类比之前我们在Kibana进行的ES的相关操作，这样使用起来更加有效果 ###

![1227483-20180623191506381-1909949862.png][]

### 1. Create index 创建索引 ###

CreateIndexDemo.java

package com.study.es_java_client;
 
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 
 import org.elasticsearch.action.admin.indices.alias.Alias;
 import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
 import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentType;
 
 public class CreateIndexDemo {
 
 public static void main(String[] args) {
 //这里和RESTful风格不同
 try (TransportClient client = InitDemo.getClient();) {
 
 // 1、创建 创建索引request
 CreateIndexRequest request = new CreateIndexRequest("mess");
 
 // 2、设置索引的settings
 request.settings(Settings.builder().put("index.number_of_shards", 3) // 分片数
 .put("index.number_of_replicas", 2) // 副本数
 .put("analysis.analyzer.default.tokenizer", "ik_smart") // 默认分词器
 );
 
 // 3、设置索引的mappings
 request.mapping("_doc",
 " {\n" +
 " \"_doc\": {\n" +
 " \"properties\": {\n" +
 " \"message\": {\n" +
 " \"type\": \"text\"\n" +
 " }\n" +
 " }\n" +
 " }\n" +
 " }",
 XContentType.JSON);
 
 // 4、 设置索引的别名
 request.alias(new Alias("mmm"));
 
 // 5、 发送请求 这里和RESTful风格不同
 CreateIndexResponse createIndexResponse = client.admin().indices()
 .create(request).get();
 
 // 6、处理响应
 boolean acknowledged = createIndexResponse.isAcknowledged();
 boolean shardsAcknowledged = createIndexResponse
 .isShardsAcknowledged();
 System.out.println("acknowledged = " + acknowledged);
 System.out.println("shardsAcknowledged = " + shardsAcknowledged);
 
 // listener方式发送请求
 /*ActionListener<CreateIndexResponse> listener = new ActionListener<CreateIndexResponse>() {
 @Override
 public void onResponse(
 CreateIndexResponse createIndexResponse) {
 // 6、处理响应
 boolean acknowledged = createIndexResponse.isAcknowledged();
 boolean shardsAcknowledged = createIndexResponse
 .isShardsAcknowledged();
 System.out.println("acknowledged = " + acknowledged);
 System.out.println(
 "shardsAcknowledged = " + shardsAcknowledged);
 }
 
 @Override
 public void onFailure(Exception e) {
 System.out.println("创建索引异常：" + e.getMessage());
 }
 };
 client.admin().indices().create(request, listener);
 */
 } catch (IOException | InterruptedException | ExecutionException e) {
 e.printStackTrace();
 }
 }
 }

### 2. index document ###

索引文档，即往索引里面放入文档数据.类似于数据库里面向表里面插入一行数据，一行数据就是一个文档  
IndexDocumentDemo.java

package com.study.es_java_client;
 
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.DocWriteResponse;
 import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.index.IndexResponse;
 import org.elasticsearch.action.support.replication.ReplicationResponse;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.rest.RestStatus;
 
 public class IndexDocumentDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 //这里和RESTful风格不同
 try (TransportClient client = InitDemo.getClient();) {
 // 1、创建索引请求
 IndexRequest request = new IndexRequest(
 "mess", //索引
 "_doc", // mapping type
 "11"); //文档id 
 
 // 2、准备文档数据
 // 方式一：直接给JSON串
 String jsonString = "{" +
 "\"user\":\"kimchy\"," +
 "\"postDate\":\"2013-01-30\"," +
 "\"message\":\"trying out Elasticsearch\"" +
 "}";
 request.source(jsonString, XContentType.JSON); 
 
 // 方式二：以map对象来表示文档
 /*
 Map<String, Object> jsonMap = new HashMap<>();
 jsonMap.put("user", "kimchy");
 jsonMap.put("postDate", new Date());
 jsonMap.put("message", "trying out Elasticsearch");
 request.source(jsonMap); 
 */
 
 // 方式三：用XContentBuilder来构建文档
 /*
 XContentBuilder builder = XContentFactory.jsonBuilder();
 builder.startObject();
 {
 builder.field("user", "kimchy");
 builder.field("postDate", new Date());
 builder.field("message", "trying out Elasticsearch");
 }
 builder.endObject();
 request.source(builder); 
 */
 
 // 方式四：直接用key-value对给出
 /*
 request.source("user", "kimchy",
 "postDate", new Date(),
 "message", "trying out Elasticsearch");
 */
 
 //3、其他的一些可选设置
 /*
 request.routing("routing"); //设置routing值
 request.timeout(TimeValue.timeValueSeconds(1)); //设置主分片等待时长
 request.setRefreshPolicy("wait_for"); //设置重刷新策略
 request.version(2); //设置版本号
 request.opType(DocWriteRequest.OpType.CREATE); //操作类别 
 */
 
 //4、发送请求
 IndexResponse indexResponse = null;
 try {
 //方式一： 用client.index 方法，返回是 ActionFuture<IndexResponse>，再调用get获取响应结果
 indexResponse = client.index(request).get();
 
 //方式二：client提供了一个 prepareIndex方法，内部为我们创建IndexRequest
 /*IndexResponse indexResponse = client.prepareIndex("mess","_doc","11")
 .setSource(jsonString, XContentType.JSON)
 .get();*/
 
 //方式三：request + listener
 //client.index(request, listener); 
 
 } catch(ElasticsearchException e) {
 // 捕获，并处理异常
 //判断是否版本冲突、create但文档已存在冲突
 if (e.status() == RestStatus.CONFLICT) {
 logger.error("冲突了，请在此写冲突处理逻辑！\n" + e.getDetailedMessage());
 }
 
 logger.error("索引异常", e);
 }catch (InterruptedException | ExecutionException e) {
 logger.error("索引异常", e);
 }
 
 
 
 
 //5、处理响应
 if(indexResponse != null) {
 String index = indexResponse.getIndex();
 String type = indexResponse.getType();
 String id = indexResponse.getId();
 long version = indexResponse.getVersion();
 if (indexResponse.getResult() == DocWriteResponse.Result.CREATED) {
 System.out.println("新增文档成功，处理逻辑代码写到这里。");
 } else if (indexResponse.getResult() == DocWriteResponse.Result.UPDATED) {
 System.out.println("修改文档成功，处理逻辑代码写到这里。");
 }
 // 分片处理信息
 ReplicationResponse.ShardInfo shardInfo = indexResponse.getShardInfo();
 if (shardInfo.getTotal() != shardInfo.getSuccessful()) {
 
 }
 // 如果有分片副本失败，可以获得失败原因信息
 if (shardInfo.getFailed() > 0) {
 for (ReplicationResponse.ShardInfo.Failure failure : shardInfo.getFailures()) {
 String reason = failure.reason(); 
 System.out.println("副本失败原因：" + reason);
 }
 }
 }
 
 
 //listener 方式
 /*ActionListener<IndexResponse> listener = new ActionListener<IndexResponse>() {
 @Override
 public void onResponse(IndexResponse indexResponse) {
 
 }
 
 @Override
 public void onFailure(Exception e) {
 
 }
 };
 client.index(request, listener);
 */
 
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

### 3. get document  ###

获取文档数据  
GetDocumentDemo.java

package com.study.es_java_client;
 
 import java.io.IOException;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.get.GetRequest;
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.fetch.subphase.FetchSourceContext;
 
 public class GetDocumentDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 //这里和RESTful风格不同
 try (TransportClient client = InitDemo.getClient();) {
 // 1、创建获取文档请求
 GetRequest request = new GetRequest(
 "mess", //索引
 "_doc", // mapping type
 "11"); //文档id 
 
 // 2、可选的设置
 //request.routing("routing");
 //request.version(2);
 
 //request.fetchSourceContext(new FetchSourceContext(false)); //是否获取_source字段
 //选择返回的字段
 String[] includes = new String[]{"message", "*Date"};
 String[] excludes = Strings.EMPTY_ARRAY;
 FetchSourceContext fetchSourceContext = new FetchSourceContext(true, includes, excludes);
 request.fetchSourceContext(fetchSourceContext); 
 
 //也可写成这样
 /*String[] includes = Strings.EMPTY_ARRAY;
 String[] excludes = new String[]{"message"};
 FetchSourceContext fetchSourceContext = new FetchSourceContext(true, includes, excludes);
 request.fetchSourceContext(fetchSourceContext);*/
 
 
 // 取stored字段
 /*request.storedFields("message"); 
 GetResponse getResponse = client.get(request);
 String message = getResponse.getField("message").getValue();*/
 
 
 //3、发送请求 
 GetResponse getResponse = null;
 try {
 getResponse = client.get(request).get();
 } catch (ElasticsearchException e) {
 if (e.status() == RestStatus.NOT_FOUND) {
 logger.error("没有找到该id的文档" );
 }
 if (e.status() == RestStatus.CONFLICT) {
 logger.error("获取时版本冲突了，请在此写冲突处理逻辑！" );
 }
 logger.error("获取文档异常", e);
 }catch (InterruptedException | ExecutionException e) {
 logger.error("索引异常", e);
 }
 
 //4、处理响应
 if(getResponse != null) {
 String index = getResponse.getIndex();
 String type = getResponse.getType();
 String id = getResponse.getId();
 if (getResponse.isExists()) { // 文档存在
 long version = getResponse.getVersion();
 String sourceAsString = getResponse.getSourceAsString(); //结果取成 String 
 Map<String, Object> sourceAsMap = getResponse.getSourceAsMap(); // 结果取成Map
 byte[] sourceAsBytes = getResponse.getSourceAsBytes(); //结果取成字节数组
 
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info(sourceAsString);
 
 } else {
 logger.error("没有找到该id的文档" );
 }
 }
 
 
 //异步方式发送获取文档请求
 /*
 ActionListener<GetResponse> listener = new ActionListener<GetResponse>() {
 @Override
 public void onResponse(GetResponse getResponse) {
 
 }
 
 @Override
 public void onFailure(Exception e) {
 
 }
 };
 client.getAsync(request, listener);
 */
 
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

### 4. Bulk ###

批量索引文档，即批量往索引里面放入文档数据.类似于数据库里面批量向表里面插入多行数据，一行数据就是一个文档  
BulkDemo.java

### 5. search ###

搜索数据  
SearchDemo.java

package com.study.es_java_client;
 
 import java.io.IOException;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.action.search.ShardSearchFailure;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 
 public class SearchDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (TransportClient client = InitDemo.getClient();) {
 
 // 1、创建search请求
 //SearchRequest searchRequest = new SearchRequest();
 SearchRequest searchRequest = new SearchRequest("bank"); 
 searchRequest.types("_doc");
 
 // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
 SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
 
 //构造QueryBuilder
 /*QueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("user", "kimchy")
 .fuzziness(Fuzziness.AUTO)
 .prefixLength(3)
 .maxExpansions(10);
 sourceBuilder.query(matchQueryBuilder);*/
 
 sourceBuilder.query(QueryBuilders.termQuery("age", 24)); 
 sourceBuilder.from(0); 
 sourceBuilder.size(10); 
 sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS)); 
 
 //是否返回_source字段
 //sourceBuilder.fetchSource(false);
 
 //设置返回哪些字段
 /*String[] includeFields = new String[] {"title", "user", "innerObject.*"};
 String[] excludeFields = new String[] {"_type"};
 sourceBuilder.fetchSource(includeFields, excludeFields);*/
 
 //指定排序
 //sourceBuilder.sort(new ScoreSortBuilder().order(SortOrder.DESC)); 
 //sourceBuilder.sort(new FieldSortBuilder("_uid").order(SortOrder.ASC));
 
 // 设置返回 profile 
 //sourceBuilder.profile(true);
 
 //将请求体加入到请求中
 searchRequest.source(sourceBuilder);
 
 // 可选的设置
 //searchRequest.routing("routing");
 
 // 高亮设置
 /*
 HighlightBuilder highlightBuilder = new HighlightBuilder(); 
 HighlightBuilder.Field highlightTitle =
 new HighlightBuilder.Field("title"); 
 highlightTitle.highlighterType("unified"); 
 highlightBuilder.field(highlightTitle); 
 HighlightBuilder.Field highlightUser = new HighlightBuilder.Field("user");
 highlightBuilder.field(highlightUser);
 sourceBuilder.highlighter(highlightBuilder);*/
 
 
 //加入聚合
 /*TermsAggregationBuilder aggregation = AggregationBuilders.terms("by_company")
 .field("company.keyword");
 aggregation.subAggregation(AggregationBuilders.avg("average_age")
 .field("age"));
 sourceBuilder.aggregation(aggregation);*/
 
 //做查询建议
 /*SuggestionBuilder termSuggestionBuilder =
 SuggestBuilders.termSuggestion("user").text("kmichy"); 
 SuggestBuilder suggestBuilder = new SuggestBuilder();
 suggestBuilder.addSuggestion("suggest_user", termSuggestionBuilder); 
 sourceBuilder.suggest(suggestBuilder);*/
 
 //3、发送请求 
 SearchResponse searchResponse = client.search(searchRequest).get();
 
 
 //4、处理响应
 //搜索结果状态信息
 RestStatus status = searchResponse.status();
 TimeValue took = searchResponse.getTook();
 Boolean terminatedEarly = searchResponse.isTerminatedEarly();
 boolean timedOut = searchResponse.isTimedOut();
 
 //分片搜索情况
 int totalShards = searchResponse.getTotalShards();
 int successfulShards = searchResponse.getSuccessfulShards();
 int failedShards = searchResponse.getFailedShards();
 for (ShardSearchFailure failure : searchResponse.getShardFailures()) {
 // failures should be handled here
 }
 
 //处理搜索命中文档结果
 SearchHits hits = searchResponse.getHits();
 
 long totalHits = hits.getTotalHits();
 float maxScore = hits.getMaxScore();
 
 SearchHit[] searchHits = hits.getHits();
 for (SearchHit hit : searchHits) {
 // do something with the SearchHit
 
 String index = hit.getIndex();
 String type = hit.getType();
 String id = hit.getId();
 float score = hit.getScore();
 
 //取_source字段值
 String sourceAsString = hit.getSourceAsString(); //取成json串
 Map<String, Object> sourceAsMap = hit.getSourceAsMap(); // 取成map对象
 //从map中取字段值
 /*
 String documentTitle = (String) sourceAsMap.get("title"); 
 List<Object> users = (List<Object>) sourceAsMap.get("user");
 Map<String, Object> innerObject = (Map<String, Object>) sourceAsMap.get("innerObject");
 */
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info(sourceAsString);
 
 //取高亮结果
 /*Map<String, HighlightField> highlightFields = hit.getHighlightFields();
 HighlightField highlight = highlightFields.get("title"); 
 Text[] fragments = highlight.fragments(); 
 String fragmentString = fragments[0].string();*/
 }
 
 // 获取聚合结果
 /*
 Aggregations aggregations = searchResponse.getAggregations();
 Terms byCompanyAggregation = aggregations.get("by_company"); 
 Bucket elasticBucket = byCompanyAggregation.getBucketByKey("Elastic"); 
 Avg averageAge = elasticBucket.getAggregations().get("average_age"); 
 double avg = averageAge.getValue();
 */
 
 // 获取建议结果
 /*Suggest suggest = searchResponse.getSuggest(); 
 TermSuggestion termSuggestion = suggest.getSuggestion("suggest_user"); 
 for (TermSuggestion.Entry entry : termSuggestion.getEntries()) { 
 for (TermSuggestion.Entry.Option option : entry) { 
 String suggestText = option.getText().string();
 }
 }
 */
 
 //异步方式发送获查询请求
 /*
 ActionListener<SearchResponse> listener = new ActionListener<SearchResponse>() {
 @Override
 public void onResponse(SearchResponse getResponse) {
 //结果获取
 }
 
 @Override
 public void onFailure(Exception e) {
 //失败处理
 }
 };
 client.searchAsync(searchRequest, listener); 
 */
 
 } catch (IOException | InterruptedException | ExecutionException e) {
 logger.error(e);
 }
 }
 }

### 6. highlight 高亮 ###

HighlightDemo.java

package com.study.es_java_client;
 
 import java.io.IOException;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.text.Text;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.search.SearchHits;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
 import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
 
 public class HighlightDemo {
 
 private static Logger logger = LogManager.getRootLogger(); 
 
 public static void main(String[] args) {
 try (TransportClient client = InitDemo.getClient();) {
 
 // 1、创建search请求
 SearchRequest searchRequest = new SearchRequest("hl_test"); 
 
 // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
 SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
 
 //构造QueryBuilder
 QueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("title", "lucene solr");
 sourceBuilder.query(matchQueryBuilder);
 
 //分页设置
 /*sourceBuilder.from(0); 
 sourceBuilder.size(5); ;*/ 
 
 
 // 高亮设置
 HighlightBuilder highlightBuilder = new HighlightBuilder(); 
 highlightBuilder.requireFieldMatch(false).field("title").field("content")
 .preTags("").postTags("");
 //不同字段可有不同设置，如不同标签
 /*HighlightBuilder.Field highlightTitle = new HighlightBuilder.Field("title"); 
 highlightTitle.preTags("").postTags("");
 highlightBuilder.field(highlightTitle); 
 HighlightBuilder.Field highlightContent = new HighlightBuilder.Field("content");
 highlightContent.preTags("").postTags("");
 highlightBuilder.field(highlightContent).requireFieldMatch(false);*/
 
 sourceBuilder.highlighter(highlightBuilder);
 
 searchRequest.source(sourceBuilder);
 
 //3、发送请求 
 SearchResponse searchResponse = client.search(searchRequest).get();
 
 
 //4、处理响应
 if(RestStatus.OK.equals(searchResponse.status())) {
 //处理搜索命中文档结果
 SearchHits hits = searchResponse.getHits();
 long totalHits = hits.getTotalHits();
 
 SearchHit[] searchHits = hits.getHits();
 for (SearchHit hit : searchHits) { 
 String index = hit.getIndex();
 String type = hit.getType();
 String id = hit.getId();
 float score = hit.getScore();
 
 //取_source字段值
 //String sourceAsString = hit.getSourceAsString(); //取成json串
 Map<String, Object> sourceAsMap = hit.getSourceAsMap(); // 取成map对象
 //从map中取字段值
 /*String title = (String) sourceAsMap.get("title"); 
 String content = (String) sourceAsMap.get("content"); */
 logger.info("index:" + index + " type:" + type + " id:" + id);
 logger.info("sourceMap : " + sourceAsMap);
 //取高亮结果
 Map<String, HighlightField> highlightFields = hit.getHighlightFields();
 HighlightField highlight = highlightFields.get("title"); 
 if(highlight != null) {
 Text[] fragments = highlight.fragments(); //多值的字段会有多个值
 if(fragments != null) {
 String fragmentString = fragments[0].string();
 logger.info("title highlight : " + fragmentString);
 //可用高亮字符串替换上面sourceAsMap中的对应字段返回到上一级调用
 //sourceAsMap.put("title", fragmentString);
 }
 }
 
 highlight = highlightFields.get("content"); 
 if(highlight != null) {
 Text[] fragments = highlight.fragments(); //多值的字段会有多个值
 if(fragments != null) {
 String fragmentString = fragments[0].string();
 logger.info("content highlight : " + fragmentString);
 //可用高亮字符串替换上面sourceAsMap中的对应字段返回到上一级调用
 //sourceAsMap.put("content", fragmentString);
 }
 }
 }
 }
 
 } catch (IOException | InterruptedException | ExecutionException e) {
 logger.error(e);
 }
 }
 }

### 7. suggest 查询建议 ###

SuggestDemo.java

package com.study.es_java_client;
    
    import java.io.IOException;
    import java.util.concurrent.ExecutionException;
    
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.Logger;
    import org.elasticsearch.action.search.SearchRequest;
    import org.elasticsearch.action.search.SearchResponse;
    import org.elasticsearch.client.transport.TransportClient;
    import org.elasticsearch.rest.RestStatus;
    import org.elasticsearch.search.builder.SearchSourceBuilder;
    import org.elasticsearch.search.suggest.Suggest;
    import org.elasticsearch.search.suggest.SuggestBuilder;
    import org.elasticsearch.search.suggest.SuggestBuilders;
    import org.elasticsearch.search.suggest.SuggestionBuilder;
    import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
    import org.elasticsearch.search.suggest.term.TermSuggestion;
    
    public class SuggestDemo {
        
        private static Logger logger = LogManager.getRootLogger();  
        
        //拼写检查
        public static void termSuggest(TransportClient client) {
                
            // 1、创建search请求
            //SearchRequest searchRequest = new SearchRequest();
            SearchRequest searchRequest = new SearchRequest("mess"); 
            
            // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
            SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
             
            sourceBuilder.size(0); 
            
            //做查询建议        
            //词项建议
            SuggestionBuilder termSuggestionBuilder =
                    SuggestBuilders.termSuggestion("user").text("kmichy"); 
            SuggestBuilder suggestBuilder = new SuggestBuilder();
            suggestBuilder.addSuggestion("suggest_user", termSuggestionBuilder);     
            sourceBuilder.suggest(suggestBuilder);
            
            searchRequest.source(sourceBuilder);    
    
            try{
                //3、发送请求        
                SearchResponse searchResponse = client.search(searchRequest).get();
                
                
                //4、处理响应
                //搜索结果状态信息
                if(RestStatus.OK.equals(searchResponse.status())) {
                    // 获取建议结果
                    Suggest suggest = searchResponse.getSuggest(); 
                    TermSuggestion termSuggestion = suggest.getSuggestion("suggest_user"); 
                    for (TermSuggestion.Entry entry : termSuggestion.getEntries()) { 
                        logger.info("text: " + entry.getText().string());
                        for (TermSuggestion.Entry.Option option : entry) { 
                            String suggestText = option.getText().string();
                            logger.info("   suggest option : " + suggestText);
                        }
                    }
                }
    
            } catch (InterruptedException | ExecutionException e) {
                logger.error(e);
            }
                /*
                  "suggest": {
                    "my-suggestion": [
                      {
                        "text": "tring",
                        "offset": 0,
                        "length": 5,
                        "options": [
                          {
                            "text": "trying",
                            "score": 0.8,
                            "freq": 1
                          }
                        ]
                      },
                      {
                        "text": "out",
                        "offset": 6,
                        "length": 3,
                        "options": []
                      },
                      {
                        "text": "elasticsearch",
                        "offset": 10,
                        "length": 13,
                        "options": []
                      }
                    ]
                  }*/
    
        }
        //自动补全
        public static void completionSuggester(TransportClient client) {
                    
            // 1、创建search请求
            //SearchRequest searchRequest = new SearchRequest();
            SearchRequest searchRequest = new SearchRequest("music"); 
            
            // 2、用SearchSourceBuilder来构造查询请求体 ,请仔细查看它的方法，构造各种查询的方法都在这。
            SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); 
             
            sourceBuilder.size(0); 
            
            //做查询建议        
            //自动补全
            /*POST music/_search?pretty
                    {
                        "suggest": {
                            "song-suggest" : {
                                "prefix" : "lucene s", 
                                "completion" : { 
                                    "field" : "suggest" ,
                                    "skip_duplicates": true
                                }
                            }
                        }
                    }*/
    
            SuggestionBuilder termSuggestionBuilder =
                    SuggestBuilders.completionSuggestion("suggest").prefix("lucene s")
                    .skipDuplicates(true); 
            SuggestBuilder suggestBuilder = new SuggestBuilder();
            suggestBuilder.addSuggestion("song-suggest", termSuggestionBuilder);     
            sourceBuilder.suggest(suggestBuilder);
            
            searchRequest.source(sourceBuilder);    
                
            try {
                //3、发送请求        
                SearchResponse searchResponse = client.search(searchRequest).get();
                
                
                //4、处理响应
                //搜索结果状态信息
                if(RestStatus.OK.equals(searchResponse.status())) {
                    // 获取建议结果
                    Suggest suggest = searchResponse.getSuggest(); 
                    CompletionSuggestion termSuggestion = suggest.getSuggestion("song-suggest"); 
                    for (CompletionSuggestion.Entry entry : termSuggestion.getEntries()) { 
                        logger.info("text: " + entry.getText().string());
                        for (CompletionSuggestion.Entry.Option option : entry) { 
                            String suggestText = option.getText().string();
                            logger.info("   suggest option : " + suggestText);
                        }
                    }
                }
    
            } catch (InterruptedException | ExecutionException e) {
                logger.error(e);
            }
        }
    
        public static void main(String[] args) {
            try (TransportClient client = InitDemo.getClient();) {
                termSuggest(client);
                
                logger.info("--------------------------------------");
                
                completionSuggester(client);
            } catch (IOException e) {
                logger.error(e);
            }
        }
    }

### 8. aggregation 聚合分析 ###

AggregationDemo.java

###  9. 官网文档 ###

Document API 文档操作API：

[https://www.elastic.co/guide/en/elasticsearch/client/java-api/6.2/java-docs.html][https_www.elastic.co_guide_en_elasticsearch_client_java-api_6.2_java-docs.html]

Search API：

[https://www.elastic.co/guide/en/elasticsearch/client/java-api/6.2/java-search.html][https_www.elastic.co_guide_en_elasticsearch_client_java-api_6.2_java-search.html]

##  六、Spring Data Elasticsearch ##

ES与Spring集成使用，可以作为了解，个人建议还是使用原生的ES的java客户端

官网链接：

[https://docs.spring.io/spring-data/elasticsearch/docs/current/reference/html/][https_docs.spring.io_spring-data_elasticsearch_docs_current_reference_html]

代码库：

[https://github.com/spring-projects/spring-data-elasticsearch][https_github.com_spring-projects_spring-data-elasticsearch]

## 七、源代码获取地址 ##

[https://github.com/leeSmall/Elasticsearch-Java-client-api][https_github.com_leeSmall_Elasticsearch-Java-client-api]

[1227483-20180623183417689-1254706105.png]: /images/20220221/2187180e56084fd189bfec37cec45547.png
[1227483-20180623183533451-186611934.png]: /images/20220221/4f65d14f54ec402ba182820ddd8a4861.png
[1227483-20180623183916238-1857758044.png]: /images/20220221/e94f8e40388b4e74b25f0f32a54828b5.png
[1227483-20180623184101432-1336166083.png]: /images/20220221/4778cdd779944e2c860eb802c67556e5.png
[1227483-20180623184216237-824072141.png]: /images/20220221/25079e5fc93443649a38e214cc2cdccc.png
[https_www.elastic.co_guide_en_elasticsearch_client_index.html]: https://www.elastic.co/guide/en/elasticsearch/client/index.html
[https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-low.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-low.html
[https_artifacts.elastic.co_javadoc_org_elasticsearch_client_elasticsearch-rest-client_6.2.4_index.html.]: https://artifacts.elastic.co/javadoc/org/elasticsearch/client/elasticsearch-rest-client/6.2.4/index.html.
[https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-supported-apis.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-supported-apis.html
[1227483-20180623191506381-1909949862.png]: /images/20220221/446240d195f44639a3429a67840d38fa.png
[https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-query-builders.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-query-builders.html
[https_www.elastic.co_guide_en_elasticsearch_client_java-rest_current_java-rest-high-aggregation-builders.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-aggregation-builders.html
[https_www.elastic.co_guide_en_elasticsearch_client_java-api_current_index.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-api/current/index.html
[1227483-20180623201145595-1312856554.png]: /images/20220221/368428479965449a845cc36e30c4cfad.png
[https_www.elastic.co_guide_en_elasticsearch_client_java-api_6.2_java-docs.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-api/6.2/java-docs.html
[https_www.elastic.co_guide_en_elasticsearch_client_java-api_6.2_java-search.html]: https://www.elastic.co/guide/en/elasticsearch/client/java-api/6.2/java-search.html
[https_docs.spring.io_spring-data_elasticsearch_docs_current_reference_html]: https://docs.spring.io/spring-data/elasticsearch/docs/current/reference/html/
[https_github.com_spring-projects_spring-data-elasticsearch]: https://github.com/spring-projects/spring-data-elasticsearch
[https_github.com_leeSmall_Elasticsearch-Java-client-api]: https://github.com/leeSmall/Elasticsearch-Java-client-api