Elasticsearch Rest Client

2019独角兽企业重金招聘Python工程师标准>>>

    从ElasticSearch(后续简称ES)5.0开始，官方推出了自己的Rest Client（在此之前，我们使用Jest提供Rest风格的ES访问）。由于官网的Demo比较简单，在此列举几个常规的使用方法。

Java Rest Client官方地址：https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/index.html

Java API官方地址：https://www.elastic.co/guide/en/elasticsearch/client/java-api/current/index.html

 

初始化RestClient

RestClient restClient = RestClient.builder(
                new HttpHost("127.0.0.1", 8310, "http"),
                new HttpHost("127.0.0.1", 8210, "http"),
                new HttpHost("127.0.0.1", 8110, "http"))
                .build();

 

写入操作

        // 可以使用json工具类、Pojo等方式生成json串
        JSONObject demo = new JSONObject();
        demo.put("user_id", 1L);
        demo.put("user_name", "yan");
        demo.put("age", 30);
        String json = demo.toJSONString();

        // http消息体
        HttpEntity httpEntity = new StringEntity(json, ContentType.APPLICATION_JSON);

        // http uri, eg. /user/basic/${id}
        String indexEndPoint = new StringBuffer()
                .append("/").append(index)
                .append("/").append(type)
                .append("/").append(id)
                .toString();

        // 该方法会抛出IOException, 根据需要进行处理
        Response response = restClient.performRequest("PUT",
                indexEndPoint,
                Collections.emptyMap(),
                httpEntity);

        // 获取http请求结果状态，可以与org.apache.http.HttpStatus的类聚类进行判断，新数据status_code = 201, 更新status_code = 200
        int statusCode = response.getStatusLine().getStatusCode();

 

读取操作

        // 构造Query DSL，推荐使用es官方java api
        QueryBuilder queryBuilder = QueryBuilders.boolQuery().must(QueryBuilders.termQuery("id", 1));

        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        searchSourceBuilder.query(queryBuilder);
        searchSourceBuilder.from(0).size(10);

        HttpEntity httpEntity = new StringEntity(searchSourceBuilder.toString(), ContentType.APPLICATION_JSON);

        // http uri, eg. /user/basic/_search
        String searchEndPoint = new StringBuffer()
                .append("/").append(index)
                .append("/").append(type)
                .append("/_search")
                .toString();

        // 该操作会抛出IOException；第三个参数paramMap可以添加es优化类属性，eg. pretty、rounting等
        Response response = restClient.performRequest("GET",
                searchEndPoint,
                Collections.emptyMap(),
                httpEntity);

        /*
            {
                "took": 2,
                "timed_out": false,
                "_shards": {
                    "total": 5,
                    "successful": 5,
                    "failed": 0
                },
                "hits": {
                    "total": 1,
                    "max_score": 1,
                    "hits": [
                        {
                            "_index": "user",
                            "_type": "basic",
                            "_id": "1",
                            "_score": 1,
                            "_source": {
                                "age": 25,
                                "id": 1,
                                "name": "lee"
                            }
                        }
                    ]
                }
            }
        */
        String originReponseLine = EntityUtils.toString(response.getEntity());

 

转载于:https://my.oschina.net/SEyanlei/blog/907631