SpringBoot整合ElasticSearch

齐先生，我没有对这个世界失望，我只是对自己很失望。

1. 引入对应的pom依赖（使用es-rest-high-level-client来调用es)

<!-- es -->
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>${elasticsearch.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.elasticsearch.client</groupId>
                    <artifactId>elasticsearch-rest-client</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.elasticsearch</groupId>
                    <artifactId>elasticsearch</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch</groupId>
            <artifactId>elasticsearch</artifactId>
            <version>7.17.6</version>
        </dependency>
        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-client</artifactId>
            <version>7.17.6</version>
        </dependency>

注意：这里需要观察里面对应es的版本，如果与你服务器上安装的es版本不一样的话，会报找不到包的异常。

如：

Java ElasticsearchException.toXContent

查看版本对不对应看引入elasticsearch-rest-high-level-client，如果不对应排除掉，重新引入对应的。

2. 设置配置类

/**
 * @Description es请求配置类
 * es添加了安全访问规则，访问es需要添加一个安全头，就可以通过requestOptions设置
 * @Author lh
 * @Date 2022/9/21 21:16
 */
@Configuration
public class GuliESConfig {
​
    @Value("${es.host}")
    private String ES_HOST;
​
    public static final RequestOptions COMMON_OPTIONS;
​
    static {
        RequestOptions.Builder builder = RequestOptions.DEFAULT.toBuilder();
        COMMON_OPTIONS = builder.build();
    }
​
    @Bean
    @SuppressWarnings(value = "all")
    public RestHighLevelClient esRestClient() {
        RestClientBuilder builder = null;
        // 可以指定多个es
        builder = RestClient.builder(new HttpHost(ES_HOST, 9200, "http"));
​
        return new RestHighLevelClient(builder);
    }
}

3. 测试保存数据

@SpringBootTest
public class GulimallSearchTest {
​
    @Autowired
    @SuppressWarnings(value = "all")
    private RestHighLevelClient esRestClient;
​
    @Test
    public void indexData() throws IOException {
        // 设置索引
        IndexRequest indexRequest = new IndexRequest("user");
        indexRequest.id("1");
​
        User user = new User();
        user.setUserName("李嘉图");
        user.setAge(18);
        user.setGender("男");
        String jsonString = JSON.toJSONString(user);
​
        // 设置要保存的内容，指定数据和类型
        indexRequest.source(jsonString, XContentType.JSON);
​
        // 执行创建索引和保存数据
        IndexResponse index = esRestClient.index(indexRequest, GuliESConfig.COMMON_OPTIONS);
        System.out.println(index);
    }
}

结果：

IndexResponse[index=user,type=_doc,id=1,version=3,result=updated,seqNo=2,primaryTerm=1,shards={"total":2,"successful":1,"failed":0}]

4. 测试获取数据

   @Test
    public void find() throws IOException {
        // 创建索引请求
        SearchRequest searchRequest = new SearchRequest();
        searchRequest.indices("user");
​
        // 设置检索条件
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
//        sourceBuilder.query();
//        sourceBuilder.from();
//        sourceBuilder.size();
//        sourceBuilder.aggregation();
        sourceBuilder.query(QueryBuilders.matchQuery("userName", "李嘉图"));
        System.out.println(sourceBuilder.toString());
        searchRequest.source(sourceBuilder);
​
        // 执行检索
        SearchResponse searchResponse = esRestClient.search(searchRequest, GuliESConfig.COMMON_OPTIONS);
        System.out.println(searchResponse);
    }

结果：

{"took":24,"timed_out":false,"_shards":{"total":1,"successful":1,"skipped":0,"failed":0},"hits":{"total":{"value":1,"relation":"eq"},"max_score":0.8630463,"hits":[{"_index":"user","_type":"_doc","_id":"1","_score":0.8630463,"_source":{"age":18,"gender":"男","userName":"李嘉图"}}]}}