Elasticsearch Java 从入门到出家教程 Demo (一)1. 安装Elasticsearch 2. 新

Elasticsearch 是一个开源的搜索引擎，建立在一个全文搜索引擎库 Apache Lucene™ 基础之上。 Lucene 可以说是当下最先进、高性能、全功能的搜索引擎库—无论是开源还是私有。

Elasticsearch 也是使用 Java 编写的，它的内部使用 Lucene 做索引与搜索，但是它的目的是使全文检索变得简单，通过隐藏 Lucene 的复杂性，取而代之的提供一套简单一致的 RESTful API。

——Elasticsearch: 权威指南

本教程系列目录：

1. 安装Elasticsearch

官方文档

从官网 elastic.co/downloads/elasticsearch 下载所需版本（本教程使用7.9.2版本）的 Elasticsearch
解压安装Elasticsearch，安装说明

运行Elasticsearch：

cd elasticsearch安装目录
./bin/elasticsearch

验证Elasticsearch 是否启动成功：浏览器访问 http://localhost:9200/
推荐使用Chrome插件ElasticSearch Head，进行ES数据的管理、查看与查询等常用操作

2. 新建Spring Boot Maven项目

Github源码：github.com/Mengzuozhu/…

本项目Postman RESTful请求示例（可导入到Postman）

本教程的项目结构：

3. Maven引用

elasticsearch关键引用：

        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>${elasticsearch.version}</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>${elasticsearch.version}</version>
        </dependency>

pom文件内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.mzz</groupId>
    <artifactId>es-demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>es-demo</name>
    <description>ES Demo</description>

    <properties>
        <java.version>1.8</java.version>
        <elasticsearch.version>7.9.2</elasticsearch.version>
        <commons-collections4.version>4.4</commons-collections4.version>
        <fastjson.version>1.2.68</fastjson.version>
        <guava.version>30.1-jre</guava.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <artifactId>assertj-core</artifactId>
                    <groupId>org.assertj</groupId>
                </exclusion>
                <exclusion>
                    <artifactId>junit-vintage-engine</artifactId>
                    <groupId>org.junit.vintage</groupId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>${elasticsearch.version}</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>${elasticsearch.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>${fastjson.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>${commons-collections4.version}</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>${guava.version}</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

4. 配置elasticsearch

application.properties文件内容

server.port=8080

# your es http url
es.http.url=http://localhost:9200

新建ElasticsearchConfig.java类文件

package com.mzz.esdemo.config;

import com.mzz.esdemo.common.util.EsClientUtil;
import org.elasticsearch.client.IndicesClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * The type Elasticsearch config.
 *
 * @author Zero
 */
@Configuration
public class ElasticsearchConfig {
    @Value("${es.http.url}")
    private String esUrl;

    @Bean
    RestHighLevelClient restHighLevelClient() {
        return EsClientUtil.createRestHighLevelClient(esUrl);
    }

    @Bean
    IndicesClient indicesClient() {
        return restHighLevelClient().indices();
    }
}

EsClientUtil.java工具类

package com.mzz.esdemo.common.util;

import org.apache.commons.lang3.StringUtils;
import org.apache.http.HttpHost;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import org.elasticsearch.client.RestHighLevelClient;

import java.net.URI;
import java.net.URISyntaxException;

/**
 * The type Es client util.
 *
 * @author Zero
 */
public class EsClientUtil {

    /**
     * Create rest high level client.
     *
     * @param esUrl the es url
     * @return the rest high level client
     */
    public static RestHighLevelClient createRestHighLevelClient(String esUrl) {
        return new RestHighLevelClient(getRestClientBuilder(esUrl));
    }

    /**
     * Create rest high level client.
     *
     * @param esIp   the es ip
     * @param esPort the es port
     * @return the rest high level client
     */
    public static RestHighLevelClient createRestHighLevelClient(String esIp, Integer esPort) {
        return new RestHighLevelClient(RestClient.builder(new HttpHost(esIp, esPort, "http")));
    }

    /**
     * Create rest high level client.
     *
     * @param esUrl    the es url
     * @param userName the user name
     * @param password the password
     * @return the rest high level client
     */
    public static RestHighLevelClient createRestHighLevelClient(String esUrl, String userName, String password) {
        CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(userName, password));
        RestClientBuilder restClientBuilder = getRestClientBuilder(esUrl)
                .setHttpClientConfigCallback(httpClientBuilder -> {
                    httpClientBuilder.disableAuthCaching();
                    return httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider);
                });
        return new RestHighLevelClient(restClientBuilder);
    }

    /**
     * Create rest high level client with keep alive.
     *
     * @param esUrl     the es url
     * @param keepAlive the keep alive
     * @return the rest high level client
     */
    public static RestHighLevelClient createRestHighLevelClientWithKeepAlive(String esUrl, Long keepAlive) {
        RestClientBuilder clientBuilder = getRestClientBuilder(esUrl)
                .setHttpClientConfigCallback(requestConfig ->
                        requestConfig.setKeepAliveStrategy((response, context) -> keepAlive));
        return new RestHighLevelClient(clientBuilder);
    }

    /**
     * Gets rest client builder.
     *
     * @param esUrl the es url
     * @return the rest client builder
     */
    public static RestClientBuilder getRestClientBuilder(String esUrl) {
        return RestClient.builder(createHttpHost(URI.create(esUrl)));
    }

    /**
     * Create http host.
     *
     * @param uri the uri
     * @return the http host
     */
    public static HttpHost createHttpHost(URI uri) {
        if (StringUtils.isEmpty(uri.getUserInfo())) {
            return HttpHost.create(uri.toString());
        }
        try {
            return HttpHost.create(new URI(uri.getScheme(), null, uri.getHost(), uri.getPort(), uri.getPath(),
                    uri.getQuery(), uri.getFragment()).toString());
        } catch (URISyntaxException ex) {
            throw new IllegalStateException(ex);
        }
    }
}

Elasticsearch Java 从入门到出家 教程 Demo (一)

1. 安装Elasticsearch

2. 新建Spring Boot Maven项目

3. Maven引用

4. 配置elasticsearch

Elasticsearch Java 从入门到出家教程 Demo (一)