ElasticSearch在Java中实现增删改查

Bertha 。 2022-02-19 05:39 451阅读 0赞

# ElasticSearch在Java中实现增删改查 #

ElasticSearch6.x

1.  从es中获取数据
2.   添加一条文档
3.  删除一条文档
4.  使用update更新,局部更新，前提必须有数据
5.  使用upsert更新,局部更新，之前沒有則創建，有則更新

如果是ElasticSearch7或以上版本情转到如下链接

REST高级客户端-DocumentApi：[https://blog.csdn.net/u014646662/article/details/96473156][https_blog.csdn.net_u014646662_article_details_96473156]

REST高级客户端SearchApi：[https://blog.csdn.net/u014646662/article/details/96853830][https_blog.csdn.net_u014646662_article_details_96853830]

更多新的查询方式（ElasticSearch相关文档）：[https://blog.csdn.net/u014646662/article/category/8747782][https_blog.csdn.net_u014646662_article_category_8747782]

对人工智能感兴趣的同学，可以点击以下链接：

[现在人工智能非常火爆，很多朋友都想学，但是一般的教程都是为博硕生准备的，太难看懂了。最近发现了一个非常适合小白入门的教程，不仅通俗易懂而且还很风趣幽默。所以忍不住分享一下给大家。点这里可以跳转到教程。][Link 1]

[https://www.cbedai.net/u014646662][Link 1]

话不多说直接看代码

package cn.com.es.test;
    
    import java.io.IOException;
    import java.net.InetAddress;
    import java.net.UnknownHostException;
    
    import org.elasticsearch.action.delete.DeleteResponse;
    import org.elasticsearch.action.get.GetResponse;
    import org.elasticsearch.action.index.IndexRequest;
    import org.elasticsearch.action.index.IndexResponse;
    import org.elasticsearch.action.update.UpdateRequest;
    import org.elasticsearch.action.update.UpdateResponse;
    import org.elasticsearch.client.transport.TransportClient;
    import org.elasticsearch.common.settings.Settings;
    import org.elasticsearch.common.transport.TransportAddress;
    import org.elasticsearch.common.xcontent.XContentBuilder;
    import org.elasticsearch.common.xcontent.XContentFactory;
    import org.elasticsearch.transport.client.PreBuiltTransportClient;
    import org.junit.Test;
    
    public class ESTest {
    
    	/**
    	 * 从es中获取数据
    	 * 
    	 * @throws UnknownHostException
    	 */
    	@Test
    	public void query1() throws UnknownHostException {
    		// 指定ES集群
    		Settings settings = Settings.builder().put("cluster.name", "my-application").build();
    		System.out.println(settings);
    		// 创建ES客户端，客户端端口号默认9300，不要写web端口9200
    		@SuppressWarnings("resource")
    		TransportClient client = new PreBuiltTransportClient(settings)
    				.addTransportAddress(new TransportAddress(InetAddress.getByName("master"), 9300));
    		// 数据查询
    		GetResponse response = client.prepareGet("lib", "user", "1").execute().actionGet();
    
    		System.out.println(response.getSourceAsString());
    
    		client.close();
    	}
    
    	/**
    	 * 添加一条文档
    	 * 
    	 * @throws IOException
    	 */
    	@Test
    	public void add1() throws IOException {
    		// 指定ES集群
    		Settings settings = Settings.builder().put("cluster.name", "my-application").build();
    		System.out.println(settings);
    		// 创建ES客户端，客户端端口号默认9300，不要写web端口9200
    		@SuppressWarnings("resource")
    		TransportClient client = new PreBuiltTransportClient(settings)
    				.addTransportAddress(new TransportAddress(InetAddress.getByName("master"), 9300));
    
    		// 构建文档数据
    		XContentBuilder doc = XContentFactory.jsonBuilder().startObject().field("first_name", "Green")
    				.field("last_name", "Smith").field("age", 32).field("about", "I like to collect rock albums")
    				.array("interests", "music", "dance").endObject();
    		// 添加文档
    		IndexResponse response = client.prepareIndex("lib", "user", "100").setSource(doc).get();
    
    		// 查看执行状态，创建成功后，之前没有CREATED，之前存在OK
    		System.out.println(response.status());
    		client.close();
    	}
    
    	/**
    	 * 删除一条文档
    	 * 
    	 * @throws UnknownHostException
    	 */
    	@Test
    	public void delete1() throws UnknownHostException {
    		Settings settings = Settings.builder().put("cluster.name", "my-application").build();
    		@SuppressWarnings("resource")
    		TransportClient client = new PreBuiltTransportClient(settings)
    				.addTransportAddress(new TransportAddress(InetAddress.getByName("master"), 9300));
    		DeleteResponse response = client.prepareDelete("lib", "user", "100").get();
    
    		System.out.println(response.status());
    		client.close();
    	}
    
    	/**
    	 * 使用update更新,局部更新，前提必须有数据
    	 * 
    	 * @throws Exception
    	 */
    	@org.junit.Test
    	public void update() throws Exception {
    		Settings settings = Settings.builder().put("cluster.name", "my-application").build();
    		@SuppressWarnings("resource")
    		TransportClient client = new PreBuiltTransportClient(settings)
    				.addTransportAddress(new TransportAddress(InetAddress.getByName("master"), 9300));
    		UpdateRequest request = new UpdateRequest();
    		request.index("lib").type("user").id("101").doc(XContentFactory.jsonBuilder().startObject()
    				// .field("first_name","Green")
    				// .field("last_name","Jone")
    				.field("age", 24)
    				// .field("about","keep trying no matter how hard it seems. it will get
    				// easier.")
    				// .array("interests", "music","spark","donce","bbb")
    				.endObject());
    		UpdateResponse update = client.update(request).get();
    		System.out.println(update.status());
    		GetResponse get = client.prepareGet("lib", "user", "101").execute().get();
    		System.out.println(get.getSourceAsString());
    		client.close();
    	}
    
    	/**
    	 * 使用upsert更新,局部更新，之前沒有則創建，有則更新
    	 */
    	@org.junit.Test
    	public void upsert() throws Exception {
    		Settings settings = Settings.builder().put("cluster.name", "my-application").build();
    		@SuppressWarnings("resource")
    		TransportClient client = new PreBuiltTransportClient(settings)
    				.addTransportAddress(new TransportAddress(InetAddress.getByName("master"), 9300));
    		// 沒有時，則按此數據創建
    		IndexRequest index = new IndexRequest("lib", "user", "102").source(
    				XContentFactory.jsonBuilder().startObject().field("first_name", "Green").field("last_name", "Jone")
    						.field("age", 24).field("about", "keep trying no matter how hard it seems. it will get easier.")
    						.array("interests", "music", "spark", "donce", "bbb").endObject());
    		// 有數據則按此數據更新
    		UpdateRequest update = new UpdateRequest("lib", "user", "102")
    				.doc(XContentFactory.jsonBuilder().startObject().field("age", 28).endObject()).upsert(index);
    		// 執行操作
    		UpdateResponse updateResponse = client.update(update).get();
    		// 查看狀態
    		System.out.println(updateResponse.status());
    		// 查詢執行結果
    		GetResponse get = client.prepareGet("lib", "user", "102").execute().get();
    		System.out.println(get.getSourceAsString());
    		client.close();
    	}
    }

[https_blog.csdn.net_u014646662_article_details_96473156]: https://blog.csdn.net/u014646662/article/details/96473156
[https_blog.csdn.net_u014646662_article_details_96853830]: https://blog.csdn.net/u014646662/article/details/96853830
[https_blog.csdn.net_u014646662_article_category_8747782]: https://blog.csdn.net/u014646662/article/category/8747782
[Link 1]: https://www.cbedai.net/u014646662