GET /bank/_search
{
  "query": { "match_all": {} },
  "sort": [
    { "account_number": "asc" },
    {"balance":"desc"}
  ]
}

QUERY_NAME:{
   ARGUMENT:VALUE,
   ARGUMENT:VALUE,...
}

{
  QUERY_NAME:{
     FIELD_NAME:{
       ARGUMENT:VALUE,
       ARGUMENT:VALUE,...
      }
   }
}

GET bank/_search
{
  "query": {
    "match_all": {}
  },
  "from": 0,
  "size": 5,
  "sort": [
    {
      "account_number": {
        "order": "desc"
      }
    }
  ]
}


GET bank/_search
{
  "query": {
    "match_all": {}
  },
  "from": 0,
  "size": 5,
  "sort": [
    {
      "account_number": {
        "order": "desc"
      }
    }
  ],
  "_source": ["balance","firstname"]

}

GET bank/_search
{
  "query": {
    "match": {
      "account_number": "20"
    }
  }
}

GET bank/_search
{
  "query": {
    "match": {
      "address": "Aviation Road"
    }
  }
}

GET bank/_search
{
  "query": {
    "match_phrase": {
      "address": "Aviation Road"
    }
  }
}

GET bank/_search
{
  "query": {
    "multi_match": {
      "query": "mill ",
      "fields": ["address","city"]
    }
  }
}

GET bank/_search
{
  "query": {
    "term": {
      "address": "Aviation Road"
    }
  }
}

GET bank/_search
{
   "query":{
        "bool":{
             "must":[
              {"match":{"address":"mill"}},
              {"match":{"gender":"M"}}
             ]
         }
    }
}

GET bank/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "address": "mill"
          }
        }
      ],
      "filter": {
        "range": {
          "balance": {
            "gte": "10000",
            "lte": "20000"
          }
        }
      }
    }
  }
}

GET bank/_search
{
"aggs": {
  "NAME": {
    "AGG_TYPE": {}
  }
}
}

GET bank/_search
{
  "query": {
    "match_all": {}
  },
  "aggs": {
    "年齡分組": {
      "terms": {
        "field": "age",
        "size": 10
      },
      "aggs": {
        "平均薪資": {
          "avg": {
            "field": "balance"
          }
        }
      }
    }
  },
  "size": 0
}

GET bank/_search
{
  "query": {
    "match_all": {}
  },
  "aggs": {
    "ageAgg": {
      "terms": {
        "field": "age",
        "size": 100
      },
      "aggs": {
        "genderAgg": {
          "terms": {
            "field": "gender.keyword"
          },
          "aggs": {
            "balanceAvg": {
              "avg": {
                "field": "balance"
              }
            }
          }
        },
        "ageBalanceAvg": {
          "avg": {
            "field": "balance"
          }
        }
      }
    }
  },
  "size": 0
}

POST _analyze
{
  "analyzer": "standard",
  "text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}

POST _analyze
{
  "analyzer": "ik_max_word",
  "text": "《白雪公主》是廣泛流行於歐洲的一篇德國童話，亦是該童話中的主角。其最著名的版本見於德國《格林童話》，講述了白雪公主受到繼母的虐待，逃到森林裡，遇到七個小矮人的故事"
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
	<comment>IK Analyzer 擴展配置</comment>
	<!--用户可以在這裏配置自己的擴展字典 -->
	<entry key="ext_dict"></entry>
	 <!--用户可以在這裏配置自己的擴展停止詞字典-->
	<entry key="ext_stopwords"></entry>
	<!--用户可以在這裏配置遠程擴展字典 -->
	<!-- <entry key="remote_ext_dict">words_location</entry> -->
	<!--用户可以在這裏配置遠程擴展停止詞字典-->
	<!-- <entry key="remote_ext_stopwords">words_location</entry> -->
</properties>

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.16.2</version>
</dependency>

    <properties>
        ...
        <elasticsearch.version>7.16.2</elasticsearch.version>
    </properties>

@Configuration
public class ElasticConfig {

    // 設定
    public static final RequestOptions COMMON_OPTIONS;

    static {
        RequestOptions.Builder builder = RequestOptions.DEFAULT.toBuilder();
        // builder.addHeader("Authorization", "Bearer " + TOKEN);
        // builder.setHttpAsyncResponseConsumerFactory(
        //         new HttpAsyncResponseConsumerFactory
        //                 .HeapBufferedResponseConsumerFactory(30 * 1024 * 1024 * 1024));
        COMMON_OPTIONS = builder.build();
    }

    // 已經被棄用的創造Client方法
    @Bean
    public RestHighLevelClient restHighLevelClient() {
        // Create the low-level client
        RestClientBuilder httpClientBuilder = RestClient.builder(
                new HttpHost("localhost", 9200)
        );
        // Create the HLRC
        RestHighLevelClient hlrc = new RestHighLevelClient(httpClientBuilder);
        return hlrc;
    }
}

@SpringBootTest
class EsTest {

    @Autowired
    private RestHighLevelClient client;

    @Data
    class User {
        private String name;
        private int age;

    }
    @Test
    public void test() throws IOException {
        // 建立一個測試的物件
        User user = new User();
        user.setName("Tom");
        user.setAge(30);
        String s = JSONUtil.toJsonStr(user);

        // 創立index
        IndexRequest indexRequest = new IndexRequest("users");
        // 指定id
        indexRequest.id("1");
        // 放進去的東西，如果是字串必須聲明是XContentType.JSON，否則要放map
        indexRequest.source(s, XContentType.JSON);
        // 執行，第2個參數是使用一般設定
        IndexResponse response = client.index(indexRequest, ElasticConfig.COMMON_OPTIONS);
        System.out.println("response = " + response);
    }
}

    @Test
    public void searchData() throws IOException {
        GetRequest getRequest = new GetRequest(
                "users",
                "_-2vAHIB0nzmLJLkxKWk");

        GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);
        System.out.println(getResponse);
        String index = getResponse.getIndex();
        System.out.println(index);
        String id = getResponse.getId();
        System.out.println(id);
        if (getResponse.isExists()) {
            long version = getResponse.getVersion();
            System.out.println(version);
            String sourceAsString = getResponse.getSourceAsString();
            System.out.println(sourceAsString);
            Map<String, Object> sourceAsMap = getResponse.getSourceAsMap();
            System.out.println(sourceAsMap);
            byte[] sourceAsBytes = getResponse.getSourceAsBytes();
        } else {

        }
    }

/**
     * 複雜檢索:在bank中搜索address中包含mill的所有人的年齡分佈以及平均年齡，平均薪資
     * @throws IOException
     */
@Test
public void searchData() throws IOException {
    //1. 創建檢索請求
    SearchRequest searchRequest = new SearchRequest();

    //1.1）指定索引
    searchRequest.indices("bank");
    //1.2）構造檢索條件
    SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
    sourceBuilder.query(QueryBuilders.matchQuery("address","Mill"));

    //1.2.1)按照年齡分佈進行聚合
    TermsAggregationBuilder ageAgg=AggregationBuilders.terms("ageAgg").field("age").size(10);
    sourceBuilder.aggregation(ageAgg);

    //1.2.2)計算平均年齡
    AvgAggregationBuilder ageAvg = AggregationBuilders.avg("ageAvg").field("age");
    sourceBuilder.aggregation(ageAvg);
    //1.2.3)計算平均薪資
    AvgAggregationBuilder balanceAvg = AggregationBuilders.avg("balanceAvg").field("balance");
    sourceBuilder.aggregation(balanceAvg);

    System.out.println("檢索條件："+sourceBuilder);
    searchRequest.source(sourceBuilder);
    //2. 執行檢索
    SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
    System.out.println("檢索結果："+searchResponse);

    //3. 將檢索結果封裝為Bean
    SearchHits hits = searchResponse.getHits();
    SearchHit[] searchHits = hits.getHits();
    for (SearchHit searchHit : searchHits) {
        String sourceAsString = searchHit.getSourceAsString();
        Account account = JSON.parseObject(sourceAsString, Account.class);
        System.out.println(account);
    }

    //4. 獲取聚合信息
    Aggregations aggregations = searchResponse.getAggregations();

    Terms ageAgg1 = aggregations.get("ageAgg");

    for (Terms.Bucket bucket : ageAgg1.getBuckets()) {
        String keyAsString = bucket.getKeyAsString();
        System.out.println("年齡："+keyAsString+" ==> "+bucket.getDocCount());
    }
    Avg ageAvg1 = aggregations.get("ageAvg");
    System.out.println("平均年齡："+ageAvg1.getValue());

    Avg balanceAvg1 = aggregations.get("balanceAvg");
    System.out.println("平均薪資："+balanceAvg1.getValue());
}