ElasticSearch介绍及基本API

悠悠 2023-06-15 07:19 10阅读 0赞

# 1. ES基本介绍 #

[https://blog.csdn.net/achuo/article/details/87865141][https_blog.csdn.net_achuo_article_details_87865141]Elasticsearch学习，请先看这一篇！内容比较完备，推荐阅读

# 2. API操作练习 #

<dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.12</version>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>org.elasticsearch.client</groupId>
                <artifactId>transport</artifactId>
                <version>${elasticsearch.version}</version>
            </dependency>
    
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
                <version>2.9.0</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>2.9.0</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
                <version>2.9.0</version>
            </dependency>

import org.elasticsearch.action.bulk.BulkItemResponse;
    import org.elasticsearch.action.delete.DeleteRequest;
    import org.elasticsearch.action.get.GetResponse;
    import org.elasticsearch.action.get.MultiGetItemResponse;
    import org.elasticsearch.action.get.MultiGetResponse;
    import org.elasticsearch.action.index.IndexRequest;
    import org.elasticsearch.action.index.IndexResponse;
    import org.elasticsearch.action.update.UpdateRequest;
    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.common.xcontent.XContentType;
    import org.elasticsearch.transport.client.PreBuiltTransportClient;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    
    import java.io.IOException;
    import java.net.InetAddress;
    import java.net.UnknownHostException;
    import java.util.Date;
    import java.util.HashMap;
    import java.util.Map;
    
    /**
     * @author YDAlex
     * @version 1.0
     * @description 用javaAPI操作ES集群练习
     * @data 2019/11/20.
     */
    public class EsJavaClient
    {
        
    
        private static final String INDEX = "javaindex";
        private static final String TYPE = "javatype";
        private static  TransportClient client;
    
        @Before
        public void init() throws UnknownHostException {
        
            Settings settings = Settings.builder()
                    .put("cluster.name","MyES")
                    .put("client.transport.sniff", "true")//增加自动嗅探配置
                    .build();
    
            client = new PreBuiltTransportClient(settings);
            client.addTransportAddress(new TransportAddress(InetAddress.getByName("hadoop"), 9300));
    
            System.out.println(client.toString());
        }
        @Test
        public void createIndex() {
        
            client.admin().indices().prepareCreate(INDEX).get();
            System.out.println("创建Index成功");
        }
    
        @Test
        public void deleteIndex() {
        
            client.admin().indices().prepareDelete(INDEX).get();
            System.out.println("删除Index成功");
        }
    
        //不推荐使用
        @Test
        public void createDoc() {
        
            String json = "{\"name\":\"GPY\"}";
    
            IndexResponse response = client.prepareIndex(INDEX, TYPE, "100")
                    .setSource(json, XContentType.JSON)
                    .get();
            System.out.println("返回的结果是："+response);
        }
    
        //推荐使用
        @Test
        public void createDoc01() {
        
            Map<String, Object> json = new HashMap<>();
            json.put("name", "GPY");
            json.put("message", "trying out Elasticsearch");
    
            IndexResponse response = client.prepareIndex(INDEX, TYPE, "101").setSource(json).get();
            System.out.println(response.getVersion());
        }
    
    
        //推荐使用
        @Test
        public void createDoc02() throws IOException {
        
    
            XContentBuilder builder = XContentFactory.jsonBuilder()
                    .startObject()
                    .field("user", "GPY")
                    .field("postDate", new Date())
                    .field("message", "trying out Elasticsearch")
                    .endObject();
    
            IndexResponse response = client.prepareIndex(INDEX, TYPE, "102").setSource(builder).get();
            System.out.println(response.getVersion());
        }
    
        @Test
        public void getDoc() {
        
            GetResponse response = client.prepareGet(INDEX, TYPE, "100").get();
            System.out.println(response.getSourceAsString());
        }
    
        @Test
        public void getDocsByIds() {
        
    
            MultiGetResponse responses = client.prepareMultiGet()
                    .add(INDEX, TYPE,"100")
                    .add(INDEX, TYPE, "101", "102", "1000")
                    .get();
    
            for (MultiGetItemResponse response : responses) {
        
                GetResponse res = response.getResponse();
                if (res.isExists()) {
        
                    System.out.println(res);
                } else {
        
                    System.out.println("没有这条数据");
                }
    
            }
        }
    
        @Test
        public void testBatchDealWith(){
        
            //需求使用批处理技术，操作es索引之javaindex
            //新增索引name：beam，author：haha，version：4.4.4
            //删除索引id：100
            //修改索引id为102的信息，message：has changed
    
            BulkItemResponse []itms =  client.prepareBulk()
                    .add(new IndexRequest(INDEX,TYPE).source("name","beam","author","haha","version","4.4.4"))
                    .add(new DeleteRequest(INDEX,TYPE,"100"))
                    .add(new UpdateRequest(INDEX,TYPE,"102").doc("message","has changed"))
                    .get().getItems();
    
            for (BulkItemResponse itm: itms) {
        
                itm.isFailed();
            }
    
    
        }
    
    
        @After
        public void close(){
        
            client.close();
        }
    }

[https_blog.csdn.net_achuo_article_details_87865141]: https://blog.csdn.net/achuo/article/details/87865141