1.struts2初始化

private RestHighLevelClient client = getClient();

public RestHighLevelClient getClient() {
	int num = EsConfiguration.hostList.size();
	HttpHost[] hosts = new HttpHost[num];
	for (int i = 0; i < num; i++) {
		hosts[i] = EsConfiguration.hostList.get(i);
	}
	this.client = new RestHighLevelClient(RestClient.builder(hosts));
	return client;
}

EsConfiguration.java

private static String hosts = "127.0.0.1,192.168.0.111"; // 测试地址，多个用,隔开
private static int port = 9200;
private static String schema = "http"; // 使用的协议
static ArrayList<HttpHost> hostList = null;
static {
    hostList = new ArrayList<>();
    String[] hostStrs = hosts.split(",");
    for (String host : hostStrs) {
        hostList.add(new HttpHost(host, port, schema));
    }
}

public static ArrayList<HttpHost> getHostList() {
	return hostList;
}

public static void setHostList(ArrayList<HttpHost> hostList) {
	EsConfiguration.hostList = hostList;
}

public RestHighLevelClient client() {
	RestClientBuilder builder = RestClient.builder(hostList.toArray(new HttpHost[0]));
	// 异步httpclient连接延时配置
//        builder.setRequestConfigCallback(new RequestConfigCallback() {
//            @Override
//            public Builder customizeRequestConfig(Builder requestConfigBuilder) {
//                requestConfigBuilder.setConnectTimeout(connectTimeOut);
//                requestConfigBuilder.setSocketTimeout(socketTimeOut);
//                requestConfigBuilder.setConnectionRequestTimeout(connectionRequestTimeOut);
//                return requestConfigBuilder;
//            }
//        });
//         //异步httpclient连接数配置
//        builder.setHttpClientConfigCallback(new HttpClientConfigCallback() {
//            @Override
//            public HttpAsyncClientBuilder customizeHttpClient(HttpAsyncClientBuilder httpClientBuilder) {
//                httpClientBuilder.setMaxConnTotal(maxConnectNum);
//                httpClientBuilder.setMaxConnPerRoute(maxConnectPerRoute);
//                return httpClientBuilder;
//            }
//        });
	RestHighLevelClient client = new RestHighLevelClient(builder);
	return client;
}

2.SpringMvc初始化

@Autowired
private RestHighLevelClient client;

3.需要的jar包

3.1 Maven项目

<dependency>
	<groupId>org.elasticsearch</groupId>
	<artifactId>elasticsearch</artifactId>
	<version>7.2.0</version>
</dependency>
<dependency>
	<groupId>org.elasticsearch.client</groupId>
	<artifactId>elasticsearch-rest-high-level-client</artifactId>
	<version>7.2.0</version>
	<exclusions>
		<exclusion>
			<groupId>org.elasticsearch</groupId>
			<artifactId>elasticsearch</artifactId>
		</exclusion>
	</exclusions>
</dependency>

3.2 具体jar包列表

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