Java操作ElasticSearch

我的ElasticSearch集群的版本是6.2.4,導入elasticsearch相關的maven依賴也是6.2.4,不同版本的api可能會有差異

一:maven依賴

   <!--elasticsearch核心依賴-->
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>6.2.4</version>
        </dependency>
        <!--elasticsearch客戶端-->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>transport</artifactId>
            <version>6.2.4</version>
        </dependency>
        <!--日志-->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-to-slf4j</artifactId>
            <version>2.9.1</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.24</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.7.21</version>
        </dependency>

        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>
        <!--單元測試-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>compile</scope>
        </dependency>
        <!--實體轉json-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.10.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.10.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.10.2</version>
        </dependency>

        <!--實體類簡化工具-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.18</version>
        </dependency>

2.單元測試的共有方法

  TransportClient client;

    @Before
    //創建連接
    public void connection() throws UnknownHostException {
        //創建客戶端連接對象
        //參數為config\elasticsearch.yml中對應的值 也就是集群名稱
        Settings settings = Settings.builder().put("cluster.name", "elasticsearch").build();
        client = new PreBuiltTransportClient(settings);
        client.addTransportAddress(new TransportAddress(InetAddress.getByName("192.168.118.3"), 9300));
        client.addTransportAddress(new TransportAddress(InetAddress.getByName("192.168.118.4"), 9300));
        client.addTransportAddress(new TransportAddress(InetAddress.getByName("192.168.118.5"), 9300));
    }



  @After
    //釋放資源
    public void close() {
        client.close();
    }



    //遍歷結果集
    public void iteratorSearchHit(SearchHits searchHits) {
        System.out.println("符合查詢條件有:" + searchHits.getTotalHits() + "條");
        //獲取迭代器
        Iterator<SearchHit> iterator = searchHits.iterator();
        System.out.println("開始進行遍歷------------------------------");
        while (iterator.hasNext()) {
            //獲取每個查詢對象
            SearchHit searchHit = iterator.next();
            //獲取字符串類型並進行打印
            System.out.println(searchHit.getSourceAsString());
            Map<String, Object> sourceAsMap = searchHit.getSourceAsMap();
            System.out.println("符合搜索條件的標題是:=======" + sourceAsMap.get("title"));
            /*   for (Map.Entry<String,Object> map:sourceAsMap.entrySet()){
                System.out.println("===================================");
                System.out.println(map.getKey());
                System.out.println(map.getValue());
            }
            */
        }
    }

3.常規操作

   @Test
    //創建索引庫
    public void createIndex() {
        //索引名成必須小寫
        client.admin().indices().prepareCreate("myindex1").get();
    }

    @Test
    //添加映射
    public void mapping() throws IOException, ExecutionException, InterruptedException {
        XContentBuilder builder = XContentFactory.jsonBuilder().startObject()
                .startObject("type1")
                .startObject("properties")
                .startObject("id")
                .field("type", "integer")
                .field("store", "true")
                .endObject()
                .startObject("title")
                .field("type", "text")
                .field("store", "true")
                .field("analyzer", "ik_smart")
                .endObject()
                .startObject("content")
                .field("type", "text")
                .field("store", "true")
                .field("analyzer", "ik_smart")
                .endObject()
                .endObject()
                .endObject()
                .endObject();
        PutMappingRequest mappingRequest = Requests.putMappingRequest("myindex1")
                .type("type1")
                .source(builder);
        client.admin().indices().putMapping(mappingRequest).get();
    }

    @Test
    //給myindex1的type1創建文檔
    public void createDocument() throws IOException {
        XContentBuilder xContentBuilder = XContentFactory.jsonBuilder();
        xContentBuilder.startObject()
                .field("id", 1)
                .field("title", "ElasticSearch是一個基於Lucene的搜索服務器")
                .field("content", "它提供了一個分布式多用戶能力的全文搜索引擎，基於RESTful web接口。Elasticsearch是用 Java開發的，並作為Apache許可條款下的開放源碼發布，是當前流行的企業級搜索引擎。設計用於雲計算中，能夠達到 實時搜索，穩定，可靠，快速，安裝使用方便。")
                .endObject();
        //參數1:索引名 2:類型 3:id
        client.prepareIndex("myindex1", "type1", "1").setSource(xContentBuilder).get();

    }

    @Test
    //通過實體轉json創建文檔
    public void jsonDocument() throws JsonProcessingException {
        Type1 type1 = new Type1();
        type1.setId(2);
        type1.setTitle("通過實體轉json創建文檔");
        type1.setContent("通過創建實體的方式,將實體轉json");
        ObjectMapper objectMapper = new ObjectMapper();
        client.prepareIndex("myindex1", "type1", type1.getId().toString())
                .setSource(objectMapper.writeValueAsString(type1).getBytes(), XContentType.JSON)
                .get();
    }

    @Test
    //關鍵詞查詢
    public void termQuery() {
        //設置搜索條件,目標索引庫,目標類型,目標域
        SearchResponse searchResponse = client.prepareSearch("myindex1")
                .setTypes("type1")
                .setQuery(QueryBuilders.termQuery("content", "實體")).get();
        SearchHits hits = searchResponse.getHits();
        iteratorSearchHit(hits);
    }

    @Test
    //字符串查詢
    public void stringQuery() {
        //設置搜索條件,目標索引庫,目標類型
        SearchResponse searchResponse = client.prepareSearch("myindex1")
                .setTypes("type1")
                .setQuery(QueryBuilders.queryStringQuery("搜索實體")).get();
        SearchHits hits = searchResponse.getHits();
        iteratorSearchHit(hits);
    }

    @Test
    //根據文檔ID進行查詢
    public void idQuery() {
        SearchResponse searchResponse = client.prepareSearch("myindex1")
                .setQuery(QueryBuilders.idsQuery("type1").addIds("2"))
                .get();
        iteratorSearchHit(searchResponse.getHits());
    }

    //分頁之前的操作,批量添加文檔
    @Test
    public void batchInsert() throws JsonProcessingException {
        Type1 type1;
        for (int i = 1; i <= 50; i++) {
            type1 = new Type1();
            type1.setId(i);
            type1.setTitle(i + "通過實體轉json創建文檔");
            type1.setContent(i + "通過創建實體的方式,將實體轉json");
            ObjectMapper objectMapper = new ObjectMapper();
            client.prepareIndex("myindex1", "type1", type1.getId().toString())
                    .setSource(objectMapper.writeValueAsString(type1).getBytes(), XContentType.JSON)
                    .get();
        }
    }

    //搜索文檔並分頁顯示
    @Test
    public void pageDocument() {
        SearchResponse searchResponse = client.prepareSearch("myindex1")
                .setTypes("type1")
                .setQuery(QueryBuilders.matchAllQuery())
                //setFrom()：從第幾條開始檢索，默認是0。
                // setSize():每頁最多顯示的記錄數默認是十
                .setFrom(0)
                .setSize(5)
                .get();
        iteratorSearchHit(searchResponse.getHits());
    }


    //模擬搜索結果高亮顯示
    @Test
    public void highlight() {
        //設置查詢條件
        SearchRequestBuilder searchRequestBuilder = client.prepareSearch("myindex1")
                .setTypes("type1")
                .setQuery(QueryBuilders.termQuery("title", "實體"));
        //高亮設置
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        //開頭的標簽信息
        highlightBuilder.preTags("<font style='color:red'>");
        //結尾的標簽
        highlightBuilder.postTags("</font>");
        highlightBuilder.field("title");
        searchRequestBuilder.highlighter(highlightBuilder);
        SearchResponse searchResponse = searchRequestBuilder.get();
        Iterator<SearchHit> iterator = searchResponse.getHits().iterator();
        while (iterator.hasNext()) {
            SearchHit hit = iterator.next();
            System.out.print("正常String方式打印文檔搜索內容====");
            System.out.println(hit.getSourceAsString());
            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
            //遍歷集合,輸出高亮數據
            //方式1
            Text[] titles = highlightFields.get("title").getFragments();
            for (Text str : titles) {
                System.out.println(str);
            }
        }
    }