javaAPI操作Elasticsearch

在Java中操作Elasticsearch，你可以使用Elasticsearch的Java API客户端——Elasticsearch-Rest-High-Level-Client。以下是一些基本操作的示例代码：

1. 创建客户端：

RestHighLevelClient client = new RestHighLevelClient(
        RestClient.builder(
                new HttpHost("localhost", 9200, "http"),
                new HttpHost("localhost", 9201, "http")));

2. 索引文档：

IndexRequest request = new IndexRequest("index_name");
request.id("id");
request.source(XContentType.JSON, "field", "value");
 
IndexResponse response = client.index(request, RequestOptions.DEFAULT);

3. 获取文档：

GetRequest getRequest = new GetRequest("index_name", "id");
 
GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);

4. 更新文档：

UpdateRequest updateRequest = new UpdateRequest("index_name", "id");
updateRequest.doc(XContentType.JSON, "field", "new_value");
 
UpdateResponse updateResponse = client.update(updateRequest, RequestOptions.DEFAULT);

5. 删除文档：

DeleteRequest deleteRequest = new DeleteRequest("index_name", "id");
 
DeleteResponse deleteResponse = client.delete(deleteRequest, RequestOptions.DEFAULT);

6. 搜索文档：

SearchRequest searchRequest = new SearchRequest("index_name");
 
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.query(QueryBuilders.matchQuery("field", "value"));
 
searchRequest.source(searchSourceBuilder);
 
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);

7. 关闭客户端：

client.close();

确保你的项目中包含了Elasticsearch的依赖。如果你使用Maven，可以添加如下依赖：

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.10.0</version>
</dependency>

请根据你的Elasticsearch版本选择合适的客户端版本。