Elasticsearch JavaAPI操作

| 标签 Elasticsearch 

1. 创建Maven项目，添加依赖

<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>

2. 创建客户端对象

public class ESTest_Client {
    public static void main(String[] args) throws IOException {
        
        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
            RestClient.builder(new HttpHost("hadoop102",9200))
        );
        
        //关闭ES客户端
        esClient.close();
    }
}

3. 索引操作

3.1 创建索引

public class ESTest_Index_Create {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //创建索引
        CreateIndexRequest request = new CreateIndexRequest("users");
        CreateIndexResponse response = esClient.indices().create(request, RequestOptions.DEFAULT);

        //响应状态
        boolean acknowledged = response.isAcknowledged();
        System.out.println("索引操作：" + acknowledged);

        //关闭ES客户端
        esClient.close();
    }
}

image.png 前往postman查看有没有创建成功 image.png

3.2 查看索引

public class ESTest_Index_Search {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //查询索引
        GetIndexRequest request = new GetIndexRequest("users");
        GetIndexResponse response = esClient.indices().get(request, RequestOptions.DEFAULT);

        //响应状态
        System.out.println(response.getAliases());
        System.out.println(response.getMappings());
        System.out.println(response.getSettings());

        //关闭ES客户端
        esClient.close();
    }
}

image.png

3.3 删除索引

public class ESTest_Index_Delete {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //查询索引
        DeleteIndexRequest request = new DeleteIndexRequest("users");
        AcknowledgedResponse response = esClient.indices().delete(request, RequestOptions.DEFAULT);

        //响应状态
        System.out.println(response.isAcknowledged());

        //关闭ES客户端
        esClient.close();
    }
}

前往postman确认 image.png 已经被删除

4. 文档操作

4.1 新增文档

创建数据模型

public class Users {
    private String name;
    private String sex;
    private Integer age;

    public String getName() {
        return name;
    }

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

    public String getSex() {
        return sex;
    }

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

    public Integer getAge() {
        return age;
    }

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

public class ESTest_Doc_Insert {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //插入数据
        IndexRequest request = new IndexRequest();
        request.index("users").id("1001");

        Users users = new Users();
        users.setName("zhangsan");
        users.setAge(22);
        users.setSex("男");

        //向ES插入数据，必须将数据转换成JSON格式
        ObjectMapper mapper = new ObjectMapper();
        String usersJson = mapper.writeValueAsString(users);
        request.source(usersJson, XContentType.JSON);

        IndexResponse response = esClient.index(request, RequestOptions.DEFAULT);
        System.out.println(response.getResult());

        //关闭ES客户端
        esClient.close();
    }
}

image.png image.png

4.2 修改文档

public class ESTest_Doc_Update {
    public static void main(String[] args) throws IOException {
        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //修改数据
        UpdateRequest request = new UpdateRequest();
        request.index("users").id("1001");
        request.doc(XContentType.JSON,"name","李四");

        UpdateResponse response = esClient.update(request, RequestOptions.DEFAULT);
        
        System.out.println(response.getResult());

        //关闭ES客户端
        esClient.close();
    }
}

image.png image.png

4.3 查询文档

public class ESTest_Doc_Get {
    public static void main(String[] args) throws IOException {
        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //查询数据
        GetRequest request = new GetRequest();
        request.index("users").id("1001");

        GetResponse response = esClient.get(request, RequestOptions.DEFAULT);

        System.out.println(response.getSourceAsString());

        //关闭ES客户端
        esClient.close();
    }
}

image.png

4.4 删除文档

public class ESTest_Doc_Delete {
    public static void main(String[] args) throws IOException {
        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        DeleteRequest request = new DeleteRequest();
        request.index("users").id("1001");

        DeleteResponse response = esClient.delete(request, RequestOptions.DEFAULT);

        System.out.println(response.toString());

        //关闭ES客户端
        esClient.close();
    }
}

image.png image.png

4.5 批量新增

public class ESTest_Doc_Insert_Batch {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //批量插入数据
        BulkRequest request = new BulkRequest();
        request.add(new IndexRequest().index("users").id("1001").source(XContentType.JSON,"name","张三"));
        request.add(new IndexRequest().index("users").id("1002").source(XContentType.JSON,"name","李四"));
        request.add(new IndexRequest().index("users").id("1003").source(XContentType.JSON,"name","王五"));

        BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.getTook());
        System.out.println(response.getItems());

        //关闭ES客户端
        esClient.close();
    }
}

image.png

4.6 批量删除

public class ESTest_Doc_Delete_Batch {
    public static void main(String[] args) throws IOException {

        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //批量删除数据
        BulkRequest request = new BulkRequest();

        request.add(new DeleteRequest().index("user").id("1001"));
        request.add(new DeleteRequest().index("user").id("1002"));
        request.add(new DeleteRequest().index("user").id("1003"));
        BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.getTook());
        System.out.println(response.getItems());

        //关闭ES客户端
        esClient.close();
    }
}

image.png

4.7 全量查询

public class ESTest_Doc_Query {
    public static void main(String[] args) throws IOException {
        //创建ES客户端
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("hadoop102",9200))
        );

        //全量查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        request.source(new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()));

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

        //关闭ES客户端
        esClient.close();
    }
}

image.png

4.8 条件查询

        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件termQuery
        request.source(new SearchSourceBuilder().query(QueryBuilders.termQuery("age",30)));

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.9 分页查询

        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery());
        //（当前页码-1）* 每页显示的条数
        builder.from(0);
        builder.size(2);    //每页两条数据
        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.10 查询排序

        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery());
        builder.sort("age", SortOrder.DESC);
        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.11 过滤字段

        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder().query(QueryBuilders.matchAllQuery());

        String[] excludes = {};
        String[] includes = {"name"};
        builder.fetchSource(includes,excludes);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.11 组合查询

        //6. 组合查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
//        boolQueryBuilder.must(QueryBuilders.matchQuery("age",30));
//        boolQueryBuilder.must(QueryBuilders.matchQuery("sex","男"));
//        boolQueryBuilder.mustNot(QueryBuilders.matchQuery("sex","男"));
        boolQueryBuilder.should(QueryBuilders.matchQuery("age",30));
        boolQueryBuilder.should(QueryBuilders.matchQuery("age",40));

        builder.query(boolQueryBuilder);
        
        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.12 范围查询

        //7. 范围查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("age");

        rangeQuery.gte(30);
        rangeQuery.lte(40);

        builder.query(rangeQuery);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.13 模糊查询

        //7. 模糊查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        FuzzyQueryBuilder fuzziness = QueryBuilders.fuzzyQuery("name", "王五").fuzziness(Fuzziness.ONE);//差一个字符

        builder.query(fuzziness);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

image.png

4.14 高亮查询

       //8. 高亮查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("name", "张三");

        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.preTags("<font color ='red'>");
        highlightBuilder.postTags("</font>");
        highlightBuilder.field("name");

        builder.highlighter(highlightBuilder);
        builder.query(termQueryBuilder);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

4.15 聚合查询

        //9. 聚合查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        AggregationBuilder aggregationBuilder = AggregationBuilders.max("maxAge").field("age");

        builder.aggregation(aggregationBuilder);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

4.16 分组查询

        //10. 分组查询
        SearchRequest request = new SearchRequest();
        request.indices("users");

        //构造查询条件
        SearchSourceBuilder builder = new SearchSourceBuilder();
        AggregationBuilder aggregationBuilder = AggregationBuilders.terms("ageGroup").field("age");

        builder.aggregation(aggregationBuilder);

        request.source(builder);

        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);

        SearchHits hits = response.getHits();

        System.out.println(response.getTook());
        System.out.println(hits.getTotalHits());

        for (SearchHit hit : hits) {
            System.out.println(hit.getSourceAsString());
        }

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