1. ElasticSearch
1.1 倒排索引
1.2 ElasticSearch和Mysql对比
1.3 RestClient操作
导入依赖
<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.15.0</version>
</dependency>并设置
<elasticsearch.version>7.15.0</elasticsearch.version>添加ElasticSearch配置
@Configuration
public class ElasticSearchConfig {
@Bean
public RestHighLevelClient restHighLevelClient(){
RestHighLevelClient client=new RestHighLevelClient(
RestClient.builder(new HttpHost("127.0.0.1",9200,"http"))
);
return client;
}
}索引的创建，判断是否存在，删除
CreateIndexRequest createIndexRequest=new CreateIndexRequest("test");
restHighLevelClient.indices().create(createIndexRequest, RequestOptions.DEFAULT);
//判断某个索引库是否存在
GetIndexRequest getIndexRequest=new GetIndexRequest("test");
boolean exists = restHighLevelClient.indices().exists(getIndexRequest, RequestOptions.DEFAULT);
System.out.println(exists);
//删除某个索引库
DeleteIndexRequest deleteIndexRequest=new DeleteIndexRequest("test");
restHighLevelClient.indices().delete(deleteIndexRequest,RequestOptions.DEFAULT);添加文档
IndexRequest in = new IndexRequest("test").id("1").source("{\n" +
" \"username\":\"admin\",\n" +
" \"password\":\"admin\"\n" +
"}", XContentType.JSON);
restHighLevelClient.index(in,RequestOptions.DEFAULT);查找文档
GetRequest getRequest=new GetRequest("test","1");
GetResponse getResponse = restHighLevelClient.get(getRequest, RequestOptions.DEFAULT);
System.out.println(getResponse.getSourceAsString());更新文档
//全量更新，再次写入id一样的文档，就会删除旧文档，添加新文档
IndexRequest in = new IndexRequest("test").id("1").source("{\n" +
" \"username\":\"admin\",\n" +
" \"password\":\"helloworld\"\n" +
"}", XContentType.JSON);
restHighLevelClient.index(in,RequestOptions.DEFAULT);
UpdateRequest updateRequest=new UpdateRequest("test","1");
updateRequest.doc(
"password","hello"
);
restHighLevelClient.update(updateRequest,RequestOptions.DEFAULT);删除文档
DeleteRequest deleteRequest=new DeleteRequest("test","1");
restHighLevelClient.delete(deleteRequest,RequestOptions.DEFAULT);批量导入文档
BulkRequest bulkRequest=new BulkRequest();
bulkRequest.add(new IndexRequest("test").id("2").source("{\n" +
" \"username\":\"hello\",\n" +
" \"password\":\"hello\"\n" +
"}",XContentType.JSON));
bulkRequest.add(new IndexRequest("test").id("3").source("{\n" +
" \"username\":\"world\",\n" +
" \"password\":\"world\"\n" +
"}",XContentType.JSON));
restHighLevelClient.bulk(bulkRequest,RequestOptions.DEFAULT);版权声明：本文内容由互联网用户自发贡献，该文观点仅代表作者本人。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。如发现本站有涉嫌侵权/违法违规的内容， 请发送邮件至 举报，一经查实，本站将立刻删除。
文章由极客之音整理，本文链接：https://www.bmabk.com/index.php/post/196934.html
