本文基于Java High Level REST Client 7.12
一、引入依赖
<!-- elasticsearch版本，保持与本地版本一致 -->
<elasticsearch.version>7.12.1</elasticsearch.version>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>
二、配置 RestHighLevelClient
/**
* 配置 RestHighLevelClient
*/
@Configuration
public class ElasticSearchConfig {
@Bean
public RestHighLevelClient restHighLevelClient() {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(
new HttpHost("localhost", 9200, "http")));
return client;
}
}
可以去配置文件中直接设置
三、实例
本文没有使用 ElasticSearchTemplate、ElasticSearchRestTemplate
索引操作
@Autowired
private RestHighLevelClient restHighLevelClient;
/**
* 创建索引
*/
@Test
public void createIndex() throws IOException {
// 创建索引请求
CreateIndexRequest indexRequest = new CreateIndexRequest("test4");
// 客户端执行请求，请求后获得响应
CreateIndexResponse indexResponse = restHighLevelClient.indices().create(indexRequest, RequestOptions.DEFAULT);
System.out.println(indexResponse.index()); //输出：test4
}
/**
* 获取索引，只能判断索引存不存在
*/
@Test
public void existIndex() throws IOException {
// 创建获取索引请求
GetIndexRequest request = new GetIndexRequest("test4");
boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);
System.out.println(exists);
}
/**
* 删除索引
*/
@Test
public void deleteIndexTest() throws IOException {
DeleteIndexRequest request = new DeleteIndexRequest("test4");
AcknowledgedResponse delete = restHighLevelClient.indices().delete(request, RequestOptions.DEFAULT);
System.out.println(delete.isAcknowledged());
}
文档操作
1、先定义一个实体类User：
public class User {
private String name;
private Integer age;
// 其他省略
}
2、引入fastjson依赖
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.75</version>
</dependency>
3、文档基本操作
@Autowired
private RestHighLevelClient restHighLevelClient;
/**
* 添加文档操作
*/
@Test
public void addDocumentTest() throws IOException {
User user = new User("织女", 18);
// 拿到索引
IndexRequest request = new IndexRequest("test4");
// 设置文档id
request.id("1");
// 将User对象转化为JSON，数据放入请求
request.source(JSON.toJSONString(user), XContentType.JSON);
// 客户端发送请求后获取响应
IndexResponse index = restHighLevelClient.index(request, RequestOptions.DEFAULT);
System.out.println(index.toString());
// 索引状态
System.out.println(index.status());
}
/**
* 获取文档，判断是否存在
*/
@Test
public void existDocument() throws IOException {
GetRequest request = new GetRequest("test4","1");
boolean exists = restHighLevelClient.exists(request,RequestOptions.DEFAULT);
System.out.println(exists);
}
/**
* 获取文档信息
*/
@Test
public void getDocInfo() throws IOException {
GetRequest request = new GetRequest("test4", "1");
GetResponse response = restHighLevelClient.get(request, RequestOptions.DEFAULT);
// 从响应中获取各种信息
System.out.println(response.getSourceAsString());
System.out.println(response.getVersion());
System.out.println(response);
}
/**
* 更新文档信息
*/
@Test
public void updateDocument() throws IOException {
UpdateRequest request = new UpdateRequest("test4", "1");
User user = new User("老牛", 20);
request.doc(JSON.toJSONString(user), XContentType.JSON);
UpdateResponse response = restHighLevelClient.update(request, RequestOptions.DEFAULT);
System.out.println(response.status());
System.out.println(response.toString());
}
/**
* 删除文档
*/
@Test
public void deleteDocument() throws IOException {
DeleteRequest request = new DeleteRequest("test4", "2");
DeleteResponse response = restHighLevelClient.delete(request, RequestOptions.DEFAULT);
System.out.println(response.status());
}
4、批量插入、更新、删除
/**
* 批量插入
*/
@Test
public void bulkTest() throws IOException {
BulkRequest request = new BulkRequest();
List<User> list = new ArrayList<>();
list.add(new User("大一", 18));
list.add(new User("大二", 19));
list.add(new User("大三", 17));
list.add(new User("大四", 11));
list.add(new User("大五", 12));
list.add(new User("大六", 13));
list.add(new User("大七", 14));
list.add(new User("大八", 15));
list.add(new User("大九", 16));
// 不设置id就会随机生成
// 批处理请求
for (int i = 0; i < list.size(); i++) {
// 批量更新、删除也在这里操作
request.add(new IndexRequest("test4")
.id("" + i)
.source(JSON.toJSONString(list.get(i)), XContentType.JSON));
}
BulkResponse bulk = restHighLevelClient.bulk(request, RequestOptions.DEFAULT);
System.out.println(bulk.status());
}
5、搜索查询
/**
* 搜索查询
*/
@Test
public void searchTest() throws IOException {
SearchRequest request = new SearchRequest();
// 条件构造
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
// 查询条件，用 QueryBuilders 工具类
// termQuery 精确查询
// 有中文需要在字段后加上 .keyword，如下 name.keyword
TermQueryBuilder termQuery = QueryBuilders.termQuery("name.keyword", "大二");
// 或者使用 matchQuery 精确匹配
// MatchQueryBuilder matchQuery = QueryBuilders.matchQuery("name", "大三");
sourceBuilder.query(termQuery);
// 高亮、分页等等也在这写
// 高亮构造，但是后面还需解析高亮
// HighlightBuilder highlightBuilder = new HighlightBuilder();
// sourceBuilder.highlighter(highlightBuilder);
// 把资源放入 request
request.source(sourceBuilder);
SearchResponse response = restHighLevelClient.search(request, RequestOptions.DEFAULT);
SearchHits hits = response.getHits();
System.out.println(JSON.toJSONString(hits));
}
实体注解
在这里插入代码片
@Document(indexName = "goods",type = "detail",shards = 3,replicas = 1)
public class EsGoods {
@Id
Long id;
@Field(type = FieldType.Text,analyzer = "ik_max_word")
String title; //标题
@Field(type = FieldType.Keyword)
String category;// 分类
@Field(type = FieldType.Keyword)
String brand; // 品牌
@Field(type = FieldType.Double)
Double price; // 价格
@Field(index = false, type = FieldType.Keyword)
String images; // 图片地址
}
@Document 作用在类，标记实体类为文档对象，一般有四个属性
indexName：对应索引库名称
type：对应在索引库中的类型
shards：分片数量，默认5
replicas：副本数量，默认1
@Id 作用在成员变量，标记一个字段作为id主键
@Field 作用在成员变量，标记为文档的字段，并指定字段映射属性：
type：字段类型，取值是枚举：FieldType
index：是否索引，布尔类型，默认是true
store：是否存储，布尔类型，默认是false
analyzer：分词器名称：ik_max_word
IK分词器有两种分词模式：ik_max_word和ik_smart模式。
ik_max_word： 会将文本做最细粒度的拆分
ik_smart：会做最粗粒度的拆分
