HttpClient

 <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
        </dependency>

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.junit.Test;

import java.io.IOException;

public class HttpClientTest {
    @Test
    public void test(){
        HttpClient httpClient = HttpClients.createDefault ();
        HttpGet httpGet = new HttpGet ("http://115.28.108.130:8080/DemoController/getUserById?id=1");
        try {
            HttpResponse response = httpClient.execute (httpGet);
            HttpEntity entity = response.getEntity ();
            String s = EntityUtils.toString (entity);
            System.out.println (s);
        } catch (IOException e) {
            e.printStackTrace ();
        }
    }
}

15:39:52.888 [main] DEBUG org.apache.http.impl.conn.PoolingHttpClientConnectionManager - Connection released: [id: 0][route: {}->http://115.28.108.130:8080][total kept alive: 1; route allocated: 1 of 2; total allocated: 1 of 20]
{"code":200,"object":{"age":0,"email":"test@jd.com","id":0,"username":"小强"},"success":true}