Spring RestTemplate配置底层调用使用HttpClient

import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.ClientHttpRequestFactory;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;

@Configuration
public class RestTemplateConfig {

    // @Bean
    // public RestTemplate restTemplate(ClientHttpRequestFactory factory){
    //     return new RestTemplate(factory);
    // }
    //
    // @Bean
    // public ClientHttpRequestFactory simpleClientHttpRequestFactory(){
    //     SimpleClientHttpRequestFactory factory = new SimpleClientHttpRequestFactory();
    //     factory.setConnectTimeout(15000);
    //     factory.setReadTimeout(5000);
    //     return factory;
    // }

    @Bean
    public ClientHttpRequestFactory httpRequestFactory() {
        return new HttpComponentsClientHttpRequestFactory(httpClient());
    }

    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate(httpRequestFactory());
    }

    @Bean
    public HttpClient httpClient() {
        Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("http", PlainConnectionSocketFactory.getSocketFactory())
                .register("https", SSLConnectionSocketFactory.getSocketFactory())
                .build();
        PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager(registry);
        connectionManager.setMaxTotal(3000);
        connectionManager.setDefaultMaxPerRoute(1000);

        RequestConfig requestConfig = RequestConfig.custom()
                .setSocketTimeout(3000)
                .setConnectTimeout(3000)
                .setConnectionRequestTimeout(3000)
                .build();

        return HttpClientBuilder.create()
                .setDefaultRequestConfig(requestConfig)
                .setConnectionManager(connectionManager)
                .build();
    }
 
}