1.什么是RestClient

2.实现RestClient案例

导入数据库 编写创建索引库的语句

使用copy_to可以将当前的字段拷贝到其他之中实现同时根据多个字段搜索

DSL
# 酒店的mappings
PUT /hotel
{
  "mappings": {
    "properties": {
      "id":{
        "type":"keyword"
      },
      "name":{
        "type": "text",
        "analyzer": "ik_max_word",
        "copy_to": "all"
      },
      "address":{
        "type": "keyword",
        "index": false
      },
      "price":{
        "type": "integer"
      },
      "score":{
        "type": "integer"
      },
      "brand":{
        "type": "keyword",
        "copy_to": "all"
      },"city":{
        "type": "keyword"
      },"starName":{
        "type": "keyword"
      },"business":{
        "type": "keyword",
        "copy_to": "all"
      },
      "location":{
        "type": "geo_point"
      },
      "pic":{
        "type": "keyword",
        "index": false
        
      }
      ,"all":{
         "type": "text",
        "analyzer": "ik_max_word"
      }
    }
  }
}

初始化项目中的RestClient

pom
<!--        elasticsearch-->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>7.12.1</version>
        </dependency>

springboot管理了elasticsearch的版本需要添加覆盖版本 覆盖版本 版本全部变为7.12.1（与搭建的elasticsearch一致） 在测试类中编写初始化和销毁代码

java
ublic class HotelIndexTest {
    private RestHighLevelClient client;


    @BeforeEach
    void setUp(){
        this.client = new RestHighLevelClient(RestClient.builder(HttpHost.create("http://192.168.42.10:9200")))
    }
    

    @AfterEach
    void tearDown() throws IOException {
        this.client.close();
    }
}

编写创建索引库代码

java
    @Test
    void testCreateHotelIndex() throws IOException {
        // 创建request对象
        CreateIndexRequest request = new CreateIndexRequest("hotel");
        // 请求参数
        request.source(MAPPING_TEMPLATE, XContentType.JSON);
        // 发起请求
        client.indices().create(request, RequestOptions.DEFAULT);
    }

编写一个类存放创建索引库的语句

java
package cn.itcast.hotel.constants;

public class HotelConstants {
    public final static String MAPPING_TEMPLATE = "{\n" +
            "  \"mappings\": {\n" +
            "    \"properties\": {\n" +
            "      \"id\":{\n" +
            "        \"type\":\"keyword\"\n" +
            "      },\n" +
            "      \"name\":{\n" +
            "        \"type\": \"text\",\n" +
            "        \"analyzer\": \"ik_max_word\",\n" +
            "        \"copy_to\": \"all\"\n" +
            "      },\n" +
            "      \"address\":{\n" +
            "        \"type\": \"keyword\",\n" +
            "        \"index\": false\n" +
            "      },\n" +
            "      \"price\":{\n" +
            "        \"type\": \"integer\"\n" +
            "      },\n" +
            "      \"score\":{\n" +
            "        \"type\": \"integer\"\n" +
            "      },\n" +
            "      \"brand\":{\n" +
            "        \"type\": \"keyword\",\n" +
            "        \"copy_to\": \"all\"\n" +
            "      },\"city\":{\n" +
            "        \"type\": \"keyword\"\n" +
            "      },\"starName\":{\n" +
            "        \"type\": \"keyword\"\n" +
            "      },\"business\":{\n" +
            "        \"type\": \"keyword\",\n" +
            "        \"copy_to\": \"all\"\n" +
            "      },\n" +
            "      \"location\":{\n" +
            "        \"type\": \"geo_point\"\n" +
            "      },\n" +
            "      \"pic\":{\n" +
            "        \"type\": \"keyword\",\n" +
            "        \"index\": false\n" +
            "        \n" +
            "      }\n" +
            "      ,\"all\":{\n" +
            "         \"type\": \"text\",\n" +
            "        \"analyzer\": \"ik_max_word\"\n" +
            "      }\n" +
            "    }\n" +
            "  }\n" +
            "}";
}

运行代码查询平台创建成功

java
{
  "hotel" : {
    "aliases" : { },
    "mappings" : {
      "properties" : {
        "address" : {
          "type" : "keyword",
          "index" : false
        },
        "brand" : {
          "type" : "keyword"
        },
        "business" : {
          "type" : "keyword"
        },
        "city" : {
          "type" : "keyword"
        },
        "id" : {
          "type" : "keyword"
        },
        "location" : {
          "type" : "geo_point"
        },
        "name" : {
          "type" : "text",
          "analyzer" : "ik_max_word"
        },
        "pic" : {
          "type" : "keyword",
          "index" : false
        },
        "price" : {
          "type" : "integer"
        },
        "score" : {
          "type" : "integer"
        },
        "starName" : {
          "type" : "keyword"
        }
      }
    },
    "settings" : {
      "index" : {
        "routing" : {
          "allocation" : {
            "include" : {
              "_tier_preference" : "data_content"
            }
          }
        },
        "number_of_shards" : "1",
        "provided_name" : "hotel",
        "creation_date" : "1759399676974",
        "number_of_replicas" : "1",
        "uuid" : "aRnUh_l1Thi3hABSvrbm_w",
        "version" : {
          "created" : "7120199"
        }
      }
    }
  }
}

删除索引库判断索引库是否存在

java
    @Test
    void testGetHotelIndex() throws IOException {
        // 创建request对象
        GetIndexRequest request = new GetIndexRequest("hotel");
        // 发起判断索引库是否存在
        boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
        // 输出结果
        System.out.println(exists);
    }

java
    @Test
    void testDeleteHotelIndex() throws IOException {
        // 创建request对象
        DeleteIndexRequest request = new DeleteIndexRequest("hotel");
        // 发起删除请求
        client.indices().delete(request, RequestOptions.DEFAULT);
    }

3.文档的增删改查

编写添加文档代码

java
    @Test
    void testInsertIndex() throws IOException {
        // 根据id查询hotel数据
        Hotel hotel= hotelService.getById(36934L);
        //        将hotel转成hotelDoc
        HotelDoc hotelDoc = new HotelDoc(hotel);
//        创建request对象
        IndexRequest request = new IndexRequest("hotel").id(hotelDoc.getId().toString());

        request.source(JSON.toJSONString(hotelDoc),XContentType.JSON);

        client.index(request, RequestOptions.DEFAULT);

    }

添加成功在可视化平台上查询 添加成功

根据id查询文档

java
    @Test
    void testGetDocument() throws IOException {
//        创建request对象
        GetRequest request = new GetRequest("hotel","36934");
//        获取response
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
//        解析返回数据
        String json = response.getSourceAsString();
//        打印结果
        HotelDoc hotelDoc = JSON.parseObject(json,HotelDoc.class);
        System.out.println(hotelDoc.toString());
    }