2.JavaAPI操作elasticsearch

4.2.2 索引查询

public class ESTest_Index_Search {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http")));
// 查询索引
GetIndexRequest request = new GetIndexRequest("user");
GetIndexResponse respOnse= client.indices().get(request, RequestOptions.DEFAULT);
// 别名操作
System.out.println(response.getAliases());
// 结构
System.out.println(response.getMappings());

client.close();
}
}

输出：

{user=[]}
{user=org.elasticsearch.cluster.metadata.MappingMetadata@e2704661}

4.2.3 索引删除

public class DeleteIndex {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http")));
// 删除索引 - 请求对象
DeleteIndexRequest request = new DeleteIndexRequest("user");
// 发送请求，获取响应
AcknowledgedResponse respOnse= client.indices().delete(request,RequestOptions.DEFAULT);
// 操作结果
System.out.println("操作结果 ： " + response.isAcknowledged());
client.close();
}
}

 输出true：

4.3 文档操作

4.3.1 新建实体类

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
private String name;
private String sex;
private Integer age;
}

4.3.2 插入数据

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

// 插入数据,这里需要的是index
IndexRequest indexRequest = new IndexRequest();
// 索引名字，索引的id
indexRequest.index("user").id("1001");
User user = new User();
user.setName("zhangsan");
user.setAge(30);
user.setSex("男");
// 向ES插入数据，必须将数据转换为json格式
ObjectMapper mapper = new ObjectMapper();
String value = mapper.writeValueAsString(user);
// 放到请求体中
indexRequest.source(value, XContentType.JSON);
IndexResponse respOnse= client.index(indexRequest, RequestOptions.DEFAULT);
//输出：CREATED
System.out.println(response.getResult());
client.close();
}
}

postman获取文档，发现其已经创建成功！

4.3.3 修改数据

public class ESTest_Doc_Update {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http")));
//修改数据
UpdateRequest request=new UpdateRequest();
request.index("user").id("1001");
request.doc(XContentType.JSON,"sex","女");
UpdateResponse respOnse= client.update(request, RequestOptions.DEFAULT);
//输出：UPDATED
System.out.println(response.getResult());
client.close();
}
}

4.3.4 查询数据

/**
* 查询数据
*/
public class ESTest_Doc_Query {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http")));
GetRequest request=new GetRequest().index("user").id("1001");
GetResponse respOnse= client.get(request, RequestOptions.DEFAULT);
//打印信息
System.out.println("_index:" + response.getIndex());
System.out.println("_type:" + response.getType());
System.out.println("_id:" + response.getId());
System.out.println("source:" + response.getSourceAsString());
}
}

输出：

_index:user
_type:_doc
_id:1001
source:{"name":"zhangsan","sex":"女","age":30}

4.3.5 数据删除

/**
* 删除数据
*/
public class ESTest_Doc_Delete {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http")));
//创建请求对象
DeleteRequest request = new DeleteRequest().index("user").id("1001");
//客户端发送请求，获取响应对象
DeleteResponse respOnse= client.delete(request, RequestOptions.DEFAULT);
//打印信息
System.out.println(response.toString());
}
}

输出：

DeleteResponse[index=user,type=_doc,id=1001,version=3,result=deleted,shards=ShardInfo{total=2, successful=1, failures=[]}]