        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>2.0.20</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>7.10.1</version>
            <exclusions>
                <exclusion>
                    <groupId>org.elasticsearch</groupId>
                    <artifactId>elasticsearch</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>7.10.1</version>
        </dependency>

2 建立目录与文件

3 配置文件

spring:
  elasticsearch:
    uris: localhost:9200
    connection-timeout: 3000
    socket-timeout: 5000

4 实体类

package com.example.eslearn.entity;

import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.Field;
import org.springframework.data.elasticsearch.annotations.FieldType;

import java.io.Serializable;

/**
 *  Document:  将这个类对象转为 es 中一条文档进行录入
 * indexName: 用来指定文档的索引名称
 * createIndex: 用来指定是否创建索引,默认为false
 */
@Document(indexName = "user", createIndex = true)
public class UserDocument implements Serializable {
    @Id // 用来将放入对象id值作为文档_id进行映射
    private String id;
    @Field(type = FieldType.Keyword)    // 字段映射类型
    private String name;
    private String sex;
    private Integer age;
    @Field(type = FieldType.Text)    // 字段映射类型

    private String city;

1 使用ElasticsearchOperations的方式

优点：更想我们的springdata的使用风格，简单，快捷，个人使用

新增文档

    private final ElasticsearchOperations ESO;
    // set方法注入
    @Autowired
    public CRUDService2(ElasticsearchOperations elasticsearchOperations) {
        this.ESO = elasticsearchOperations;
    }
    // 新增文档
    public String save() {
        UserDocument user = new UserDocument();
        user.setName("说不定看见的");
        user.setCity("北京 上海 西安");
        user.setAge(22);
        user.setSex("男");
        UserDocument save = ESO.save(user);
        System.out.println(save);
        return JSON.toJSONString(save);
    }

使用可视化软件查询，得到下面的结果

更新文档

    // 更新文档
    public String update() {
        UserDocument user = new UserDocument();
        user.setId("W7w2HYcB32f1ZLmxRwzw");
        user.setName("说快来打见的");
        user.setCity("北京 上海 西安");
        user.setAge(21);
        user.setSex("女");
        UserDocument save = ESO.save(user);
        System.out.println(save);
        return JSON.toJSONString(save);
    }

删除文档

    // 删除
    public String delete(){
        UserDocument userDocument = new UserDocument();
        userDocument.setId("8966e506-1763-4d4b-bf1c-4f5d9bd9b052");
        return ESO.delete(userDocument);
    }

查询所有

    // 查询所有
    public String findAll(){
        //查询所有
        SearchHits<UserDocument> search = ESO.search(Query.findAll(), UserDocument.class);
        for (SearchHit<UserDocument> uc : search) {
            System.out.println(uc.getContent());
        }
        return JSON.toJSONString(search);
    }

查询指定id

    // 根据id查询文档
    public String getById(){
        UserDocument userDocument = ESO.get("W7w2HYcB32f1ZLmxRwzw", UserDocument.class);
        return JSON.toJSONString(userDocument);
    }

分页+指定条件+高亮显示+排序+过滤结果

服务层

 //大杂烩，一次学会
    public String findSource(){
        //查询条件构建
        MatchQueryBuilder mp=new MatchQueryBuilder("name","妲己");

        //排序构建
        FieldSortBuilder f = new FieldSortBuilder("age");
        //分页构建
        Pageable page= PageRequest.of(0,5);
        // 高亮构建
        HighlightBuilder highlightBuilder = new HighlightBuilder()
                .preTags("<span style='color:yellow'>")
                .postTags("</span>")
                .field("name");
        //结果过滤构建,相当于返回那些字段
        FetchSourceFilter filter = new FetchSourceFilter(new String[]{"name", "city"}, null);
        //查询语句构建
        NativeSearchQueryBuilder  query = new NativeSearchQueryBuilder()
                .withQuery(mp)
                .withSorts(f)
                .withPageable(page)
                .withHighlightBuilder(highlightBuilder)
                .withSourceFilter(filter);
        //执行查询
        SearchHits<UserDocument> search = ESO.search(query.build(), UserDocument.class);
        return JSON.toJSONString(search);
    }

控制器

    @GetMapping("/findSource")
    private String findSource(){
        return sv.findSource();
    }

2 使用RestHighLevelClient的方式

优点：安全，企业级常用

精确查询

对应的原生查询语句

注意这里的term就是精准查询到关键字

GET user/_search
{
  "query": {
    "term": {
      "city": "上海"
    }
    
  }
}

服务层

    // 文档搜索
    public String searchDocument(String indexName,String city){
        //2 构建搜索请求
        SearchRequest searchRequest = new SearchRequest().indices(indexName);
        //3 构建搜索内容
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("city", city);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        searchSourceBuilder.query(termQueryBuilder);
        //4 填充搜索内容
        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = null;
        try {
            //5 执行搜索操作
            searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        //6 返回值
        return JSON.toJSONString(searchResponse.getHits().getHits());
    }

控制器


    @GetMapping("/searchUserByCity")
    public String searchUserByCity() throws IOException {
        return service.searchDocument("user","上海");
    }

访问链接localhost:8080/searchUserByCity

分页查询

GET user/_search
{
  "query": {
    "term": {
      "city": "上海"
    }
    
  },
  "from":0,
  "size":5
}

服务层

  // 文档搜索--分页查询
    public String searchDocument2(String indexName,String city){
        //2 构建搜索请求
        SearchRequest searchRequest = new SearchRequest().indices(indexName);
        //3 构建搜索内容
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //拿到前5条数据
        searchSourceBuilder
                .query(QueryBuilders.termQuery("city", city))
                .from(0)
                .size(5);

        //4 填充搜索内容
        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = null;
        try {
            //5 执行搜索操作
            searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        //6 返回值
        return JSON.toJSONString(searchResponse.getHits().getHits());
    }

控制层

    @GetMapping("/searchUserByCity2")
    public String searchUserByCity2() throws IOException {
        return service.searchDocument2("user","上海");
    }

访问localhost:8080/searchUserByCity2

字符匹配AND精准查询

注意这里的bool,表示使用布尔查询，其中的must是相当于SQL语句中的and的意思。

所以就是查找name中包含“妲己”并且年龄为22岁的信息，请注意不能写成"妲",因为我们在新建文档的时候是这样新建的“妲己”，那么我们如果匹配“妲”就会匹配不到，加入这样写就可以匹配到了“妲己”，请注意空格，这是分词的依据之一

ES查询语句。

GET user/_search
{
  "query": {
    "bool":{
      "must": [
        {
          "match_phrase": {
            "name": "妲己"
          }
        },
         {
          "term": {
            "age": "32"
          }
        }
      ]
    }
    
  },
  "from":0,
  "size":10
}

服务层

// 文档分词搜索+精确查询
    public String searchDocument3(String indexName,String name,Integer age){
        //2 构建搜索请求
        SearchRequest searchRequest = new SearchRequest().indices(indexName);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //3 构建复杂的查询语句
        BoolQueryBuilder bq=QueryBuilders
                .boolQuery()
                //分词匹配
                .must(QueryBuilders.matchPhraseQuery("name",name))
                //精确匹配
                .must(QueryBuilders.matchQuery("age",age));
        //4 填充搜索语句
        searchSourceBuilder
                .query(bq)
                .from(0)
                .size(5);

        //4 填充搜索内容
        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = null;
        try {
            //5 执行搜索操作
            searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        //6 返回值
        return JSON.toJSONString(searchResponse.getHits());
    }

控制层

    @GetMapping("/searchUser3")
    public String searchUser3() throws IOException {
        return service.searchDocument3("user","妲己",32);
    }

字符匹配OR精准查询

原始查询语句

GET user/_search
{
  "query": {
    "bool":{
      "should": [
        {
          "match_phrase": {
            "name": "妲己"
          }
        },
         {
          "term": {
            "age": "32"
          }
        }
      ]
    }
    
  },
  "from":0,
  "size":10
}

服务层

    // 文档分词搜索OR精确查询
    public String searchDocument4(String indexName,String name,Integer age){
        //2 构建搜索请求
        SearchRequest searchRequest = new SearchRequest().indices(indexName);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //3 构建复杂的查询语句
        BoolQueryBuilder bq=QueryBuilders
                .boolQuery()
                //分词匹配
                .should(QueryBuilders.matchPhraseQuery("name",name))
                //精确匹配
                .should(QueryBuilders.matchQuery("age",age));
        //4 填充搜索语句
        searchSourceBuilder
                .query(bq)
                .from(0)
                .size(5);

        //4 填充搜索内容
        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = null;
        try {
            //5 执行搜索操作
            searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        //6 返回值
        return JSON.toJSONString(searchResponse.getHits());
    }

控制层

    @GetMapping("/searchUser4")
    public String searchUser4() throws IOException {
        return service.searchDocument4("user","妲己",22);
    }

结果

模糊查询

原始语句

GET user/_search
{
  "query": {
    "wildcard": {
      "city": {
        "value": "上*"
      }
    }
  }
}

    // 文档模糊查询
    public String searchDocument5(String indexName,String city){
        //2 构建搜索请求
        SearchRequest searchRequest = new SearchRequest().indices(indexName);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //3 构建模糊查询的语句
        WildcardQueryBuilder bq=QueryBuilders
                .wildcardQuery("city",city);
        //4 填充搜索语句
        searchSourceBuilder
                .query(bq);

        searchRequest.source(searchSourceBuilder);
        SearchResponse searchResponse = null;
        try {
            //5 执行搜索操作
            searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        //6 返回值
        return JSON.toJSONString(searchResponse.getHits());
    }

    @GetMapping("/searchUser5")
    public String searchUser5() throws IOException {
        return service.searchDocument5("user","上*");
    }

结果