elk7.7.1【系列二】集成 Java High Level REST Client，并查询es中所有索引，索引的所有字段

1、pom.xml中集成rest-high-level-client

<dependency>
			<groupId>org.elasticsearch.client</groupId>
			<artifactId>elasticsearch-rest-high-level-client</artifactId>
			<version>7.7.1</version>
			<exclusions>
				<exclusion>
					<groupId>org.elasticsearch</groupId>
					<artifactId>elasticsearch</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<dependency>
			<groupId>org.elasticsearch</groupId>
			<artifactId>elasticsearch</artifactId>
			<version>7.7.1</version>
		</dependency>
		<dependency>
			<groupId>org.elasticsearch.client</groupId>
			<artifactId>elasticsearch-rest-client</artifactId>
			<version>7.7.1</version>
		</dependency>

2、java代码

package com.ruoyi.project.log.controller;

import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.alias.get.GetAliasesRequest;
import org.elasticsearch.client.GetAliasesResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.cluster.metadata.AliasMetaData;

import java.io.IOException;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class t {

    RestHighLevelClient client = null;

    /**
     * 获取api操作客户端
     *
     * @return
     */
    public void getClient() {
        client = new RestHighLevelClient(RestClient.builder(
                new HttpHost("192.168.81.129", 9200, "http")
        ));
    }

    /**
     * 关闭客户端
     */
    public void closeClient() {
        try {
            if (client != null) {
                client.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取所有es索引
     */
    public Set<String> getAllIndices() {
        try {
            getClient();
            GetAliasesRequest request = new GetAliasesRequest();
            GetAliasesResponse getAliasesResponse = client.indices().getAlias(request, RequestOptions.DEFAULT);
            Map<String, Set<AliasMetaData>> map = getAliasesResponse.getAliases();
            Set<String> indices = map.keySet();
            return indices;
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            closeClient();
        }
        return new HashSet<>();
    }
    // 查询所有下所有字段
    public void test() {
        try {
            //指定索引
        GetMappingsRequest getMappings = new GetMappingsRequest().indices("wxjc2-logstash-2020.08.21");
        //调用获取
        getClient();
        GetMappingsResponse getMappingResponse = client.indices().getMapping(getMappings, RequestOptions.DEFAULT);
        //处理数据
        Map<String, MappingMetaData> allMappings = getMappingResponse.mappings();
        List<Map<String, Object>> mapList = new ArrayList<>();
        for (Map.Entry<String, MappingMetaData> indexValue : allMappings.entrySet()) {
            Map<String, Object> mapping = indexValue.getValue().sourceAsMap();
            Iterator<Map.Entry<String, Object>> entries = mapping.entrySet().iterator();
            entries.forEachRemaining(stringObjectEntry -> {
                if (stringObjectEntry.getKey().equals("properties")) {
                    Map<String, Object> value = (Map<String, Object>) stringObjectEntry.getValue();
                    for (Map.Entry<String, Object> ObjectEntry : value.entrySet()) {
                        Map<String, Object> map = new HashMap<>();
                        String key = ObjectEntry.getKey();
                        Map<String, Object> value1 = (Map<String, Object>) ObjectEntry.getValue();
                        map.put(key, value1.get("type"));
                        mapList.add(map);
                    }
                }
            });
        }
        ObjectMapper objectMapper = new ObjectMapper();
        System.out.println(objectMapper.writeValueAsString(mapList));
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            closeClient();
        }
    }

    public static void main(String[] args) {
        t t = new t();
        System.out.println(t.getAllIndices());
    }
}

附Java High Level REST Client文档地址：https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high.html