ES6.6.2 使用小结

1.以下是封装了ES常用的基本方法，可以用来做一些简单的测试。

  如：获取ES的TransportClient/IndicesAdminClient、判定索引是否存在、创建索引、设置mapping、删除索引、插入文档。

package com.bas.util;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexResponse;
import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.IndicesAdminClient;
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.XContentType;
import org.elasticsearch.transport.client.PreBuiltTransportClient;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * ES工具类
 */
public class ESUtil {
    //集群名,默认值elasticsearch
    private static final String CLUSTER_NAME = "TestCluster";
    //ES集群中某个节点
    private static final String HOSTNAME = "localhost";
    //连接端口号
    private static final int TCP_PORT = 9300;
    //构建Settings对象
    private static Settings settings = Settings.builder().put("cluster.name", CLUSTER_NAME).build();
    //TransportClient对象，用于连接ES集群
    private static volatile TransportClient client;

    /**
     * 同步synchronized(*.class)代码块的作用和synchronized static方法作用一样,
     * 对当前对应的*.class进行持锁,static方法和.class一样都是锁的该类本身,同一个监听器
     * @return
     * @throws UnknownHostException
     */
    public static TransportClient getClient(){
        if(client==null){
            synchronized (TransportClient.class){
                try {
                    client=new PreBuiltTransportClient(settings)
                            .addTransportAddress(new TransportAddress(InetAddress.getByName(HOSTNAME), TCP_PORT));
                } catch (UnknownHostException e) {
                    e.printStackTrace();
                }
            }
        }
        return client;
    }

    /**
     * 获取索引管理的IndicesAdminClient
     */
    public static IndicesAdminClient getAdminClient() {
        return getClient().admin().indices();
    }

    /**
     * 判定索引是否存在
     * @param indexName
     * @return
     */
    public static boolean isExists(String indexName){
        IndicesExistsResponse response=getAdminClient().prepareExists(indexName).get();
        return response.isExists()?true:false;
    }
    /**
     * 创建索引
     * @param indexName
     * @return
     */
    public static boolean createIndex(String indexName){
        CreateIndexResponse createIndexResponse = getAdminClient()
                .prepareCreate(indexName.toLowerCase())
                .get();
        return createIndexResponse.isAcknowledged()?true:false;
    }

    /**
     * 创建索引
     * @param indexName 索引名
     * @param shards   分片数
     * @param replicas  副本数
     * @return
     */
    public static boolean createIndex(String indexName, int shards, int replicas) {
        Settings settings = Settings.builder()
                .put("index.number_of_shards", shards)
                .put("index.number_of_replicas", replicas)
                .build();
        CreateIndexResponse createIndexResponse = getAdminClient()
                .prepareCreate(indexName.toLowerCase())
                .setSettings(settings)
                .execute().actionGet();
        return createIndexResponse.isAcknowledged()?true:false;
    }

    /**
     * 为索引indexName设置mapping
     * @param indexName
     * @param typeName
     * @param mapping
     */
    public static void setMapping(String indexName, String typeName, String mapping) {
        getAdminClient().preparePutMapping(indexName)
                .setType(typeName)
                .setSource(mapping, XContentType.JSON)
                .get();
    }

    /**
     * 删除索引
     * @param indexName
     * @return
     */
    public static boolean deleteIndex(String indexName) {
        DeleteIndexResponse deleteResponse = getAdminClient()
                .prepareDelete(indexName.toLowerCase())
                .execute()
                .actionGet();
        return deleteResponse.isAcknowledged()?true:false;
    }

    /**
     * 插入文档
     * @param indexName 索引名
     * @param type 类型
     * @param doc XContentBuilder
     */
    public static void insertDocument(String indexName, String type, XContentBuilder doc) {
        IndexResponse response = getClient().prepareIndex(indexName, type)
                .setSource(doc)
                .get();
        System.out.println(response.status());
    }
    /**
     * 插入文档
     * @param indexName 索引名
     * @param type 类型
     * @param json Json格式串
     */
    public static void insertDocument(String indexName, String type, String json) {
        IndexResponse response = getClient().prepareIndex(indexName, type)
                .setSource(json, XContentType.JSON)
                .get();
        System.out.println(response.status());
    }
}

2.结合ESUtil.java ，来做一些测试。首先是创建type为"blog"的Mapping，运行CreateDemo.test()：

package com.bas.demo;

import com.bas.util.ESUtil;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.client.IndicesAdminClient;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.transport.client.PreBuiltTransportClient;
import org.junit.jupiter.api.Test;

import java.net.InetAddress;
import java.net.UnknownHostException;

import org.elasticsearch.common.xcontent.XContentBuilder;
import java.io.IOException;

import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;

public class CreateDemo {

    /**
     * 创建Index
     * @param args
     * @throws UnknownHostException
     */
    public static void main(String[] args) throws UnknownHostException {
        //1.设置集群名称
        Settings settings = Settings.builder().put("cluster.name", "TestCluster").build();
        //2.创建client
        TransportClient client = new PreBuiltTransportClient(settings)
                .addTransportAddress(new TransportAddress(InetAddress.getByName("localhost"), 9300));
        //3.获取IndicesAdminClient对象
        IndicesAdminClient indicesAdminClient = client.admin().indices();
        //4.创建索引
        CreateIndexResponse ciReponse=indicesAdminClient.prepareCreate("app_account").get();
        System.out.println(ciReponse.isAcknowledged());
    }

    /**
     * 创建Mapping
     */
    @Test
    public void test(){
        try {
            XContentBuilder builder = jsonBuilder()
                    .startObject()
                    .startObject("properties")
                    .startObject("id")
                    .field("type", "long")
                    .endObject()
                    .startObject("title")
                    .field("type", "text")
                    .field("analyzer", "ik_max_word")
                    .field("search_analyzer", "ik_max_word")
                    .field("boost", 2)
                    .endObject()
                    .startObject("content")
                    .field("type", "text")
                    .field("analyzer", "ik_max_word")
                    .field("search_analyzer", "ik_max_word")
                    .endObject()
                    .startObject("postdate")
                    .field("type", "date")
                    .field("format", "yyyy-MM-dd HH:mm:ss")
                    .endObject()
                    .startObject("url")
                    .field("type", "keyword")
                    .endObject()
                    .endObject()
                    .endObject();
            System.out.println(builder.string());
            ESUtil.setMapping("app_account", "blog", builder.string());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

3.接下来，以两种方式插入文档到blog：

package com.bas.demo;

import com.bas.util.ESUtil;
import org.elasticsearch.common.xcontent.XContentBuilder;

import java.io.IOException;

import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;

public class InsertDemo {
    public static void main(String[] args) throws IOException {
        // 方式一
        String json = "{" +
                ""id":"1"," +
                ""title":"Java連接ES"," +
                ""content":"abcdefg。"," +
                ""postdate":"2019-03-24 14:38:00"," +
                ""url":"bas.com"" +
                "}";
        System.out.println(json);

        ESUtil.insertDocument("app_account", "blog", json);

        // 方式二
        XContentBuilder doc = jsonBuilder()
                .startObject()
                .field("id","2")
                .field("title","Java插入数据到ES")
                .field("content","abcedfasdasd")
                .field("postdate","2019-03-24 14:38:00")
                .field("url","bas.com")
                .endObject();
        ESUtil.insertDocument("app_account", "blog", doc);

    }
}