Springboot 整合 Elasticsearch（三）：使用RestHighLevelClient操作ES ①
前情提要：
Springboot 整合 Elasticsearch（一）：Linux下安装 Elasticsearch 8.x
Springboot 整合 Elasticsearch（二）：使用HTTP请求来操作ES
目录
一、Springboot 整合 Elasticsearch
1、pom.xml 中添加依赖
2、application.yml 中添加配置项
3、RestHighLevelClient API介绍
3.1、连接配置类
3.2、检查索引是否存在
3.2、创建索引
3.3、删除索引
3.4、增加文档
3.5、按主键更新文档内容
3.6、按主键删除文档内容
3.7、批量添加文档
一、Springboot 整合 Elasticsearch
1、pom.xml 中添加依赖
org.elasticsearch.client
elasticsearch-rest-high-level-client
2、application.yml 中添加配置项
spring:
elasticsearch:
rest:
uris: 192.168.1.250:92003、RestHighLevelClient API介绍
3.1、连接配置类
@Component
public class EsConfig {
@Value("${spring.elasticsearch.rest.uris}")
private String uris;
/**
* 高版本客户端
*
* @return
*/
@Bean
public RestHighLevelClient restHighLevelClient() {
String[] split = uris.split(",");
HttpHost[] httpHostArray = new HttpHost[split.length];
for (int i = 0; i < split.length; i++) {
String item = split[i];
httpHostArray[i] = new HttpHost(item.split(":")[0], Integer.parseInt(item.split(":")[1]), "http");
}
// 创建RestHighLevelClient客户端
return new RestHighLevelClient(RestClient.builder(httpHostArray));
}
}3.2、检查索引是否存在
@Test
public void checkIndex() {
try {
String indexName = "forest";
boolean exists = esConfig.restHighLevelClient().indices().exists(new GetIndexRequest(indexName), RequestOptions.DEFAULT);
System.out.println("exists:" + exists);
} catch (IOException e) {
e.printStackTrace();
}
}3.2、创建索引
@Test
public void createIndex() {
try {
// 创建名为“森林”的索引
String indexName = "forest";
if (checkIndex(indexName)) {
log.info("已存在名为{}的索引", indexName);
return;
}
CreateIndexRequest createIndexRequest = new CreateIndexRequest(indexName);
CreateIndexResponse createIndexResponse = esConfig.restHighLevelClient().indices().create(createIndexRequest, RequestOptions.DEFAULT);
System.out.println("已创建索引：" + createIndexResponse.index());
} catch (IOException e) {
e.printStackTrace();
}
}
public boolean checkIndex(String indexName) {
boolean exists = false;
try {
exists = esConfig.restHighLevelClient().indices().exists(new GetIndexRequest(indexName), RequestOptions.DEFAULT);
} catch (IOException e) {
e.printStackTrace();
}
return exists;
}
3.3、删除索引
@Test
public void deleteIndex() {
String indexName = "forest";
DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest(indexName);
// 发送delete请求
try {
AcknowledgedResponse response = esConfig.restHighLevelClient().indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
System.out.println("是否已删除：" + response.isAcknowledged());
} catch (IOException e) {
e.printStackTrace();
}
}
3.4、增加文档
@Test
public void createDoc() {
try {
String indexName = "forest";
ForestDoc forestDoc = new ForestDoc();
forestDoc.setId(001L).setTitle("枫树").setImages("http://fengshu.jpg").setPrice(300.00).setInventory(600);
// 创建索引请求对象
IndexRequest indexRequest = new IndexRequest(indexName);
indexRequest.id(forestDoc.getId().toString());
indexRequest.source(JSON.toJSONString(forestDoc), XContentType.JSON);
// 设置数据刷新策略
indexRequest.setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE);
IndexResponse index = esConfig.restHighLevelClient().index(indexRequest, RequestOptions.DEFAULT);
System.out.println("状态：" + index.status().getStatus());
} catch (IOException e) {
e.printStackTrace();
}
}
⚠️RefreshPolicy 刷新策略，是WriteRequest接口中的一个内部枚举
① IMMEDIATE:
请求向ElasticSearch提交了数据，立即进行数据刷新，然后再结束请求。
优点：实时性高、操作延时短。
缺点：资源消耗高。
② WAIT_UNTIL:
请求向ElasticSearch提交了数据，等待数据完成刷新，然后再结束请求。
优点：实时性高、操作延时长。
缺点：资源消耗低。
③ NONE:
默认策略。
请求向ElasticSearch提交了数据，不关系数据是否已经完成刷新，直接结束请求。
优点：操作延时短、资源
3.5、按主键更新文档内容
修改 id 为 2 的 images字段内容
@Test
public void updateDocById() {
try {
String indexName = "forest";
String id = "2";
UpdateRequest updateRequest = new UpdateRequest(indexName, id);
Map map = new HashMap<>();
map.put("images", "http://baihuashu.jpg");
updateRequest.doc(map);
UpdateResponse update = esConfig.restHighLevelClient().update(updateRequest, RequestOptions.DEFAULT);
System.out.println("状态：" + update.status().getStatus());
} catch (IOException e) {
e.printStackTrace();
}
} 
3.6、按主键删除文档内容
@Test
public void deleteDocById() {
String indexName = "forest";
String id = "5";
DeleteRequest deleteRequest = new DeleteRequest(indexName,id);
try {
DeleteResponse delete = esConfig.restHighLevelClient().delete(deleteRequest, RequestOptions.DEFAULT);
System.out.println("状态：" + delete.status().getStatus());
} catch (IOException e) {
e.printStackTrace();
}
}
3.7、批量添加文档
@Test
public void batchCreateDoc() {
try {
String indexName = "forest";
List list = new ArrayList<>();
ForestDoc forestDoc = new ForestDoc();
forestDoc.setId(6L).setTitle("批量_柏树").setImages("http://baishu.jpg").setPrice(1100.00).setInventory(1200);
list.add(forestDoc);
ForestDoc forestDoc2 = new ForestDoc();
forestDoc2.setId(7L).setTitle("批量_苹果树").setImages("http://pingguoshu.jpg").setPrice(1200.00).setInventory(1300);
list.add(forestDoc2);
ForestDoc forestDoc3 = new ForestDoc();
forestDoc3.setId(8L).setTitle("批量_海棠树").setImages("http://haitangshu.jpg").setPrice(1300.00).setInventory(1400);
list.add(forestDoc3);
//批量导入
BulkRequest bulk = new BulkRequest(indexName);
for (ForestDoc doc : list) {
IndexRequest indexRequest = new IndexRequest();
indexRequest.id(doc.getId().toString());
indexRequest.source(JSON.toJSONString(doc), XContentType.JSON);
bulk.add(indexRequest);
}
BulkResponse bulkResponse = esConfig.restHighLevelClient().bulk(bulk, RequestOptions.DEFAULT);
System.out.println("状态：" + bulkResponse.status().getStatus());
} catch (IOException e) {
e.printStackTrace();
}
} 
