RestClient的使用

先导入Maven坐标，要和elasticsearch和kibana的版本保持一致

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

添加一个Index索引

    void createHotelIndex() throws IOException {
        //创建Request对象
        CreateIndexRequest request = new CreateIndexRequest("hotel");
        //准备请求参数，DSL语句
        request.source(MAPPING_TEMPLATE, XContentType.JSON);
        //发送请求
        client.indices().create(request, RequestOptions.DEFAULT);
    }

删除一个index索引

    void DeleteHotelIndex() throws IOException {
        //创建对象
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("hotel");
        //发送请求
        client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
    }

判断一个index索引是否存在

    void ExitHotel() throws IOException {
        GetIndexRequest request=new GetIndexRequest("hotel");
        boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
        System.err.println(exists?"索引已经存在":"索引不存在");
    }

初始化

几乎所有的操作都依赖于RestHighLevelClient这个对象

private RestHighLevelClient client;

    void setRestHighLevelClient(){
        this.client=new RestHighLevelClient(RestClient.builder(
                HttpHost.create("http://ip:9200")
        ));
    }
    
    //销毁client
    @AfterEach
    void tearDown() throws IOException {
        this.client.close();
    }

添加一个doc文档

    void testAddDocument() throws IOException {
        Hotel hotel = hotelService.getById(61083L);
        //转换为文档类型
        HotelDoc hotelDoc=new HotelDoc(hotel);

        //准备request对象
        IndexRequest request=new IndexRequest("hotel").id(hotelDoc.getId().toString());
        //准备JSON文档
        request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
        client.index(request, RequestOptions.DEFAULT);
    }

获取一个doc文档

    void testGetDocumentById() throws IOException {
        //准备请求
        GetRequest request=new GetRequest("hotel","61083");
        //发送请求，得到响应
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        //拿到数据
        String json = response.getSourceAsString();
        HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
        System.out.println(hotelDoc);
    }

局部更新文档

    void testUpdateDocument() throws IOException {
        UpdateRequest request=new UpdateRequest("hotel","61083");
        //准备发送请求
        request.doc(
                "price","123456"
        );
        //发送请求
        client.update(request,RequestOptions.DEFAULT);
    }

删除文档

    void DeleteDocument() throws IOException {
        DeleteRequest request=new DeleteRequest("hotel","61083");
        client.delete(request,RequestOptions.DEFAULT);
    }

批量添加doc文档

    void BulkRequest() throws IOException {
        List<Hotel> hotels = hotelService.list();
        BulkRequest request=new BulkRequest();
        for (Hotel hotel:hotels){
            HotelDoc hotelDoc=new HotelDoc(hotel);
            request.add(new IndexRequest("hotel")
                    .id(hotelDoc.getId().toString())
                    .source(JSON.toJSONString(hotelDoc),XContentType.JSON)
            );
        }
        //发送请求
        client.bulk(request,RequestOptions.DEFAULT);
    }