Elasticsearch 7.x入门学习-Java API操作

1 创建项目

在idea开发工具中创建Maven项目
在这里插入图片描述

修改 pom 文件，增加 Maven 依赖关系

<dependencies>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>7.8.0</version>
        </dependency>
        <!-- elasticsearch 的客户端 -->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>7.8.0</version>
        </dependency>
        <!-- elasticsearch 依赖 2.x 的 log4j -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.8.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.8.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.9</version>
        </dependency>
        <!-- junit 单元测试 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
    </dependencies>

新建ClientTest类创建客户端对象测试是否能连接

public class ClientTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        System.out.println(client);
        client.close();
    }
}

备注：9200 端口为 Elasticsearch 的 Web 通信端口，localhost 为启动 ES 服务的主机名
执行代码，查看控制台信息，没有报错证明连接成功：
在这里插入图片描述

2 索引操作

通过 Java API 客户端对象对 ES 索引进行操作

2.1 创建索引

public class IndexTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        System.out.println(client);
        // 创建索引 - 请求对象
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("user");
        // 发送请求，获取响应
        CreateIndexResponse createIndexResponse = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
        // 获取响应状态
        boolean acknowledged = createIndexResponse.isAcknowledged();
        System.out.println("操作状态 = " + acknowledged);
        client.close();
    }
}

执行结果：
在这里插入图片描述

2.2 查看索引

public class IndexTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        // 查询索引 - 请求对象
        GetIndexRequest request = new GetIndexRequest("user");
        // 发送请求，获取响应
        GetIndexResponse response = client.indices().get(request, RequestOptions.DEFAULT);
        System.out.println("aliases:" + response.getAliases());
        System.out.println("mappings:" + response.getMappings());
        System.out.println("settings:" + response.getSettings());
        client.close();
    }
}

执行结果：
在这里插入图片描述

2.3 删除索引

public class IndexTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
       DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("user");
       // 发送请求，获取响应
       AcknowledgedResponse deleteResponse = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
       System.out.println("操作状态 = " + deleteResponse.isAcknowledged());
       client.close();
    }
}

删除索引执行完成后再次查看索引会报错
在这里插入图片描述

3 文档操作

3.1 新增文档

创建数据模型实体类User

public class User {

    private String name;
    private Integer age;
    private String sex;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

创建连接，创建数据添加到文档上，没有索引的话会自动创建索引并添加文档

public class DocumentTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        createDocument(client);
        System.out.println(client);
        client.close();
    }

    private static void createDocument(RestHighLevelClient client) throws IOException {
        // 新增文档 - 请求对象
        IndexRequest request = new IndexRequest();
        // 设置索引及唯一性标识
        request.index("user").id("1001");
        // 创建数据对象
        User user = new User();
        user.setName("zhangsan");
        user.setAge(30);
        user.setSex("男");
        ObjectMapper objectMapper = new ObjectMapper();
        String productJson = objectMapper.writeValueAsString(user);
        // 添加文档数据，数据格式为 JSON 格式
        request.source(productJson, XContentType.JSON);
        // 客户端发送请求，获取响应对象
        IndexResponse response = client.index(request, RequestOptions.DEFAULT);
        // 打印结果信息
        System.out.println("_index:" + response.getIndex());
        System.out.println("_id:" + response.getId());
        System.out.println("_result:" + response.getResult());
    }
}

执行结果：
在这里插入图片描述

3.2 查询文档

根据id查询文档示例

public class DocumentTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        searchDocument(client);
        client.close();
    }

    private static void searchDocument(RestHighLevelClient client) throws IOException {
        //1.创建请求对象
        GetRequest request = new GetRequest().index("user").id("1001");
        //2.客户端发送请求，获取响应对象
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        //3.打印结果信息
        System.out.println("_index:" + response.getIndex());
        System.out.println("_type:" + response.getType());
        System.out.println("_id:" + response.getId());
        System.out.println("source:" + response.getSourceAsString());
    }
}

执行结果：
在这里插入图片描述

3.3 修改文档

根据id将sex更新为“女”代码示例：

public class DocumentTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        updateDocument(client);
        client.close();
    }

    private static void searchDocument(RestHighLevelClient client) throws IOException {
        //1.创建请求对象
        GetRequest request = new GetRequest().index("user").id("1001");
        //2.客户端发送请求，获取响应对象
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        //3.打印结果信息
        System.out.println("_index:" + response.getIndex());
        System.out.println("_type:" + response.getType());
        System.out.println("_id:" + response.getId());
        System.out.println("source:" + response.getSourceAsString());
    }

    private static void updateDocument(RestHighLevelClient client) throws IOException {
        searchDocument(client);
        UpdateRequest updateRequest = new UpdateRequest();
        updateRequest.index("user").id("1001");
        updateRequest.doc(XContentType.JSON, "sex", "女");
        UpdateResponse response = client.update(updateRequest, RequestOptions.DEFAULT);
        System.out.println("_index:" + response.getIndex());
        System.out.println("_id:" + response.getId());
        System.out.println("_result:" + response.getResult());
        searchDocument(client);
    }
}

执行结果：
在这里插入图片描述

3.4 删除文档

根据id删除文档

public class DocumentTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        deleteDocument(client);
        client.close();
    }

    private static void deleteDocument(RestHighLevelClient client) throws IOException {
        //查看文档
        searchDocument(client);
        //删除文档
        DeleteRequest deleteRequest = new DeleteRequest().index("user").id("1001");
        DeleteResponse deleteResponse = client.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(deleteResponse.toString());
        //查看文档
        searchDocument(client);

    }

    private static void searchDocument(RestHighLevelClient client) throws IOException {
        //1.创建请求对象
        GetRequest request = new GetRequest().index("user").id("1001");
        //2.客户端发送请求，获取响应对象
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        //3.打印结果信息
        System.out.println("_index:" + response.getIndex());
        System.out.println("_type:" + response.getType());
        System.out.println("_id:" + response.getId());
        System.out.println("source:" + response.getSourceAsString());
    }
}

执行结果：
在这里插入图片描述

3.5 批量操作

public class BatchTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        //创建批量新增请求对象
        BulkRequest request = new BulkRequest();
        request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "张三"));
        request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "李四"));
        request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "王五"));
        BulkResponse bulkResponse = client.bulk(request, RequestOptions.DEFAULT);
        //打印结果信息
        //打印结果信息
        System.out.println("took:" + bulkResponse.getTook());
        System.out.println("items:" + bulkResponse.getItems());
        client.close();
    }
}

执行结果：
在这里插入图片描述

批量删除操作
批量插入文档后再批量删除文档

public class BatchTest {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        //创建批量新增请求对象
        BulkRequest request = new BulkRequest();
        request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "张三"));
        request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "李四"));
        request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "王五"));
        BulkResponse bulkResponse = client.bulk(request, RequestOptions.DEFAULT);
        //打印结果信息
        System.out.println("took:" + bulkResponse.getTook());
        System.out.println("items:" + bulkResponse.getItems());

        searchDocument(client);
        BulkRequest deleteRequest = new BulkRequest();
        deleteRequest.add(new DeleteRequest().index("user").id("1001"));
        deleteRequest.add(new DeleteRequest().index("user").id("1002"));
        BulkResponse deleteResponse = client.bulk(deleteRequest, RequestOptions.DEFAULT);
        //打印结果信息
        System.out.println("took:" + deleteResponse.getTook());
        System.out.println("items:" + deleteResponse.getItems());

        searchDocument(client);
        client.close();
    }

    private static void searchDocument(RestHighLevelClient client) throws IOException {
        //1.创建请求对象
        GetRequest getRequest = new GetRequest().index("user").id("1001");
        //2.客户端发送请求，获取响应对象
        GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);
        //3.打印结果信息
        System.out.println("_index:" + getResponse.getIndex());
        System.out.println("_type:" + getResponse.getType());
        System.out.println("_id:" + getResponse.getId());
        System.out.println("source:" + getResponse.getSourceAsString());
        GetRequest getRequest2 = new GetRequest().index("user").id("1002");
        //2.客户端发送请求，获取响应对象
        GetResponse getResponse2 = client.get(getRequest2, RequestOptions.DEFAULT);
        //3.打印结果信息
        System.out.println("_index:" + getResponse2.getIndex());
        System.out.println("_type:" + getResponse2.getType());
        System.out.println("_id:" + getResponse2.getId());
        System.out.println("source:" + getResponse2.getSourceAsString());
    }
}

执行结果：
在这里插入图片描述

4 高级查询

4.1 请求体查询

4.1.1 查询所有索引数据

查询所有索引数据,代码示例

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        searchAll(client);
        client.close();
    }


    private static void searchAll(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
}

查询结果：
在这里插入图片描述

4.1.2 term查询

term查询，查询条件为关键字,代码示例：

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        termQuery(client);
        client.close();
    }

    private static void termQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        sourceBuilder.query(QueryBuilders.termQuery("age", 30));
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
}

执行结果：
在这里插入图片描述

4.1.3 分页查询
public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        pageQuery(client);
        client.close();
    }
    
    private static void pageQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        // 当前页其实索引(第一条数据的顺序号)
        sourceBuilder.from(2);
        //每页显示多少条
        sourceBuilder.size(2);
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
}

执行结果：在这里插入图片描述

4.1.2 数据排序

数据排序代码示例：

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        sort(client);
        client.close();
    }




    private static void sort(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        sourceBuilder.sort("age", SortOrder.ASC);
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }

}

执行结果
在这里插入图片描述

4.1.2 过滤字段

代码示例：

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        fetchSource(client);
        client.close();
    }

    private static void fetchSource(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        sourceBuilder.query(QueryBuilders.matchAllQuery());
        //查询字段过滤
        String[] excludes = {};
        String[] includes = {"name", "age"};
        sourceBuilder.fetchSource(includes, excludes);

        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
}

执行结果：
在这里插入图片描述

4.1.2 Bool查询
public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));![在这里插入图片描述](https://img-blog.csdnimg.cn/direct/f61e9a465dba47b69caf62250b594da0.png)

        boolQuery(client);
        client.close();
    }

    private static void boolQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //查询所有数据
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
        boolQueryBuilder.must(QueryBuilders.matchQuery("age", 30));
        boolQueryBuilder.mustNot(QueryBuilders.matchQuery("name", "zhangsan"));
        boolQueryBuilder.should(QueryBuilders.matchQuery("set", "男"));
        sourceBuilder.query(boolQueryBuilder);

        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
    }

执行结果：
在这里插入图片描述

4.1.2 范围查询
public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        rangeQuery(client);
        client.close();
    }

    private static void rangeQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("age");
        //大于等于
        rangeQuery.gte(30);
        //小于等于
        rangeQuery.lte(40);
        sourceBuilder.query(rangeQuery);

        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }

    }
}

执行结果：
在这里插入图片描述

4.1.2 模糊查询

代码示例：

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        fuzzyQuery(client);
        client.close();
    }

    private static void fuzzyQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        FuzzyQueryBuilder builder = QueryBuilders.fuzzyQuery("name", "zhangsan").fuzziness(Fuzziness.ONE);
        sourceBuilder.query(builder);

        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }

    }
    }

执行结果：
在这里插入图片描述

4.2 高亮查询

代码示例

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
        highLightQuery(client);
        client.close();
    }

    private static void highLightQuery(RestHighLevelClient client) throws IOException  {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        TermsQueryBuilder termsQueryBuilder = QueryBuilders.termsQuery("name", "zhangsan");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.query(termsQueryBuilder);
        //设置高亮字段
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.preTags("<font color='red'>");//设置标签前缀
        highlightBuilder.postTags("</font>");//设置标签后缀
        highlightBuilder.field("name");//设置高亮字段
        //设置高亮构建对象
        sourceBuilder.highlighter(highlightBuilder);
        //设置请求体
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
            //打印高亮结果
            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
            System.out.println(highlightFields);
        }

    }
    }

执行结果
在这里插入图片描述

4.3 聚合查询

4.3.1函数使用

代码示例

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));

        maxQuery(client);
        client.close();
    }

    private static void maxQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.aggregation(AggregationBuilders.max("maxAge").field("age"));
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        System.out.println(searchResponse);
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
    }

执行结果：
在这里插入图片描述

分组统计

public class SearchTest {

    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("localhost", 9200, "http")));
//        searchAll(client);
//        termQuery(client);
//        pageQuery(client);
//        sort(client);
//        fetchSource(client);
//        boolQuery(client);
//        rangeQuery(client);
//        fuzzyQuery(client);
//        highLightQuery(client);
//        maxQuery(client);
        groupByQuery(client);
        client.close();
    }


    private static void groupByQuery(RestHighLevelClient client) throws IOException {
        // 创建搜索请求对象
        SearchRequest request = new SearchRequest();
        request.indices("student");
        //构建查询的请求体
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.aggregation(AggregationBuilders.terms("age_groupby").field("age"));
        request.source(sourceBuilder);
        SearchResponse searchResponse = client.search(request, RequestOptions.DEFAULT);
        System.out.println(searchResponse.getAggregations().get("age_groupby").getType());
        //查询匹配
        SearchHits hits = searchResponse.getHits();
        System.out.println("took:" + searchResponse.getTook());
        System.out.println("timeout:" + searchResponse.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
    }
    }

在这里插入图片描述

官方Java API 文档地址：
https://www.elastic.co/guide/en/elasticsearch/client/java-api-client/current/getting-started-java.html
代码地址：https://github.com/JustCoding-Hai/es-demo

本文来自互联网用户投稿，该文观点仅代表作者本人，不代表本站立场。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如若转载，请注明出处：/a/843400.html

如若内容造成侵权/违法违规/事实不符，请联系我们进行投诉反馈qq邮箱809451989@qq.com，一经查实，立即删除！

相关文章

ubuntu2204配置anacondacuda4090nvidia驱动

ubuntu2204配置anacondacuda4090nvidia驱动

背景 某个机房的几台机器前段时间通过dnat暴露至公网后被入侵挖矿&#xff0c;为避免一些安全隐患将这几台机器执行重装系统操作&#xff1b; 这里主要记录配置nvidia驱动及cuda&anaconda。 步骤 大概分为几个步骤 禁用nouveau配置grub显示菜单install nvidia-driveri…
阅读更多...
Linux云计算 |【第一阶段】ENGINEER-DAY3

Linux云计算 |【第一阶段】ENGINEER-DAY3

主要内容&#xff1a; LVM逻辑卷管理、VDO、RAID磁盘阵列、进程管理 一、新建逻辑卷 1、什么是逻辑卷 逻辑卷&#xff08;Logical Volume&#xff09;是逻辑卷管理&#xff08;Logical Volume Management&#xff0c;LVM&#xff09;系统中的一个概念。LVM是一种用于磁盘管理…
阅读更多...
SpringBoot集成MQTT实现交互服务通信

SpringBoot集成MQTT实现交互服务通信

引言 本文是springboot集成mqtt的一个实战案例。 gitee代码库地址&#xff1a;源码地址 一、什么是MQTT MQTT&#xff08;Message Queuing Telemetry Transport&#xff0c;消息队列遥测传输协议&#xff09;&#xff0c;是一种基于发布/订阅&#xff08;publish/subscribe&…
阅读更多...
[Armbian] 部署Docker版Home Assistent，安装HACS并连接米家设备

[Armbian] 部署Docker版Home Assistent，安装HACS并连接米家设备

title: [Armbian] 部署Docker版Home Assistent&#xff0c;安装HACS并连接米家设备 date: 2024-07-21T10:51:23Z lastmod: 2024-07-21T11:40:39Z [Armbian] 部署Docker版Home Assistent&#xff0c;安装HACS并连接米家设备 官网&#xff1a;Home Assistant (home-assistant.i…
阅读更多...
sql常见50道查询练习题

sql常见50道查询练习题

sql常见50道查询练习题 1. 表创建1.1 表创建1.2 数据插入 2. 简单查询例题(3题&#xff09;2.1 查询"李"姓老师的数量2.2 查询男生、女生人数2.3 查询名字中含有"风"字的学生信息 3. 日期相关例题(6题&#xff09;3.1 查询各学生的年龄3.2 查询本周过生日的…
阅读更多...
Yolo-World网络模型结构及原理分析（一）——YOLO检测器

Yolo-World网络模型结构及原理分析（一）——YOLO检测器

文章目录 概要一、整体架构分析二、详细结构分析YOLO检测器1. Backbone2. Head3.各模块的过程和作用Conv卷积模块C2F模块BottleNeck模块SPPF模块Upsampling模块Concat模块 概要 尽管YOLO&#xff08;You Only Look Once&#xff09;系列的对象检测器在效率和实用性方面表现出色…
阅读更多...
【GraphRAG】微软 graphrag 效果实测

【GraphRAG】微软 graphrag 效果实测

GraphRAG 本文将基于以下来源&#xff0c;对Microsoft GraphRAG分析优缺点、以及示例实测分析。 1. Source 代码仓库&#xff1a; Welcome to GraphRAGhttps://microsoft.github.io/graphrag/ 微软文章1&#xff08;2024.2.13&#xff09;&#xff1a;GraphRAG: Unlocking…
阅读更多...
通过albumentation对目标检测进行数据增强（简单直接）

通过albumentation对目标检测进行数据增强（简单直接）

albumentation官方文档看不懂&#xff1f;xml文件不知道如何操作&#xff1f;下面只需要修改部分代码即可上手使用 要使用这个方法之前需要按照albumentation这个库还有一些辅助库,自己看着来安装就行 pip install albumentation pip install opencv-python pip install json…
阅读更多...
阿尔泰科技利用485模块搭建自动灌溉系统实现远程控制

阿尔泰科技利用485模块搭建自动灌溉系统实现远程控制

自动灌溉系统又叫土壤墒情监控系统&#xff0c;土壤墒情监控系统主要实现固定站无人值守情况下的土壤墒情数据的自动采集和无线传输&#xff0c;数据在监控中心自动接收入库&#xff1b;可以实现24小时连续在线监控并将监控数据通过有线、无线等传输方式实时传输到监控中心生成…
阅读更多...
破解反爬虫策略 /_guard/auto.js（二）实战

破解反爬虫策略 /_guard/auto.js（二）实战

这次我们用上篇文章讲到的方法来真正破解一下反爬虫策略&#xff0c;这两个案例是两个不同的网站&#xff0c;一个用的是 /_guard/auto.js&#xff0c;另一个用的是/_guard/delay_jump.js。经过解析发现这两个网站用的反爬虫策略基本是一模一样&#xff0c;只不过在js混淆和生成…
阅读更多...
FOG Project 文件名命令注入漏洞复现（CVE-2024-39914）

FOG Project 文件名命令注入漏洞复现（CVE-2024-39914）

0x01 产品简介 FOG是一个开源的计算机镜像解决方案，旨在帮助管理员轻松地部署、维护和克隆大量计算机。FOG Project 提供了一套功能强大的工具，使用户能够快速部署操作系统、软件和配置设置到多台计算机上，从而节省时间和精力。该项目支持基于网络的 PXE 启动、镜像创建和还…
阅读更多...
Python | Leetcode Python题解之第240题搜索二维矩阵II

Python | Leetcode Python题解之第240题搜索二维矩阵II

题目&#xff1a; 题解&#xff1a; class Solution:def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:m, n len(matrix), len(matrix[0])x, y 0, n - 1while x < m and y > 0:if matrix[x][y] target:return Trueif matrix[x][y] > tar…
阅读更多...
使用崖山YMP 迁移 Oracle/MySQL 至YashanDB 23.2 验证测试

使用崖山YMP 迁移 Oracle/MySQL 至YashanDB 23.2 验证测试

前言 首届YashanDB「迁移体验官」开放后&#xff0c;陆续收到「体验官」们的投稿&#xff0c;小崖在此把优秀的投稿文章分享给大家~今天分享的用户文章是《使用崖山YMP 迁移 Oracle/MySQL 至YashanDB 23.2 验证测试》&#xff08;作者&#xff1a;尚雷&#xff09;&#xff0c…
阅读更多...
数据结构（队列及其实现）

数据结构（队列及其实现）

概念与结构 概念&#xff1a;只允许在⼀端进⾏插⼊数据操作&#xff0c;在另⼀端进⾏删除数据操作的特殊线性表&#xff0c; 队列具有先进先出FIFO(First In First Out)原则。 ⼊队列&#xff1a;进⾏插⼊操作的⼀端称为队尾 出队列&#xff1a;进⾏删除操作的⼀端称为队头…
阅读更多...
MyBatis 持久层框架-上

MyBatis 持久层框架-上

一、Mybatis 简介 1. 简介 MyBatis 是一款优秀的持久层框架&#xff0c;它支持自定义SQL、存储过程以及高级映射。MyBatis 免除了几乎所有的 JDBC 代码以及设置参数和获取结果集的工作。MyBatis 可以通过简单的 XML 或注解来配置和映射原始类型、接口和Java POJO 为数据库中的记…
阅读更多...
使用SpringAOP解决日志记录问题+获取MyBatis执行的SQL语句（企业中常用的日志审计功能）

使用SpringAOP解决日志记录问题+获取MyBatis执行的SQL语句（企业中常用的日志审计功能）

前言 需求是这样的&#xff1a;每个接口都有不同的数据库操作。想要将这些请求和数据库操作放到日志当中&#xff0c;方便管理员查看有哪些操作被执行了。这里排除查询操作&#xff0c;只在日志中记录 update、insert、delete 这三个操作。期望的日志表中应该有每次执行的 sql …
阅读更多...
基于电鸿（电力鸿蒙）的边缘计算网关，支持定制

基于电鸿（电力鸿蒙）的边缘计算网关，支持定制

1 产品信息 边缘计算网关基于平头哥 TH1520 芯片&#xff0c;支持 OpenHarmony 小型系统&#xff0c;是 连接物联网设备和云平台的重要枢纽&#xff0c;可应用于城市基础设施&#xff0c;智能工厂&#xff0c;智能建筑&#xff0c;营业网点&#xff0c;运营 服务中心相关场…
阅读更多...
RK3568笔记四十一：DHT11驱动开发测试

RK3568笔记四十一：DHT11驱动开发测试

若该文为原创文章&#xff0c;转载请注明原文出处。 记录开发单总线&#xff0c;读取DHT11温湿度 一、DHT11介绍 DHT11是串行接口&#xff08;单线双向&#xff09;DATA 用于微处理器与 DHT11之间的通讯和同步&#xff0c;采用单总线数据格式&#xff0c;一次通讯时间4ms左右…
阅读更多...
好用的AI搜索引擎

好用的AI搜索引擎

1. 360AI 搜索 访问 360AI 搜索: https://www.huntagi.com/sites/1706642948656.html 360AI 搜索介绍&#xff1a; 360AI 搜索&#xff0c;新一代智能答案引擎&#xff0c;值得信赖的智能搜索伙伴&#xff0c;为复杂搜索提供专业支持&#xff0c;解锁更相关、更全面的答案。AI…
阅读更多...
视频汇聚，GB28181,rtsp,rtmp,sip,webrtc,视频点播等多元异构视频融合，视频通话，视频会议交互方案

视频汇聚，GB28181,rtsp,rtmp,sip,webrtc,视频点播等多元异构视频融合，视频通话，视频会议交互方案

现在视频汇聚&#xff0c;视频融合和视频互动&#xff0c;是视频技术的应用方向&#xff0c;目前客户一般有很多视频的业务系统&#xff0c;如已有GB28181的监控&#xff08;GB现在是国内主流&#xff0c;大量开源接入和商用方案&#xff09;&#xff0c;rtsp设备&#xff0c;音…
阅读更多...
最新文章

Copyright @ 2022~2023