Android部分手机4G网第一次请求很慢（wifi正常）解决方案

try {
   InetAddress[] mInetAddresses= InetAddress.getAllByName("xxxx.cn");
   for(InetAddress address: mInetAddresses){
     System.out.println(address.getHostAddress());
   }
} catch (UnknownHostException e) {
   e.printStackTrace();
}

package okhttp3;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Arrays;
import java.util.List;
/**
 * A domain name service that resolves IP addresses for host names. Most applications will use the
 * {@linkplain #SYSTEM system DNS service}, which is the default. Some applications may provide
 * their own implementation to use a different DNS server, to prefer IPv6 addresses, to prefer IPv4
 * addresses, or to force a specific known IP address.
 *
 * <p>Implementations of this interface must be safe for concurrent use.
 */
public interface Dns {
  /**
   * A DNS that uses {@link InetAddress#getAllByName} to ask the underlying operating system to
   * lookup IP addresses. Most custom {@link Dns} implementations should delegate to this instance.
   */
  Dns SYSTEM = new Dns() {
    @Override public List<InetAddress> lookup(String hostname) throws UnknownHostException {
      if (hostname == null) throw new UnknownHostException("hostname == null");
      try {
        return Arrays.asList(InetAddress.getAllByName(hostname));
      } catch (NullPointerException e) {
        UnknownHostException unknownHostException =
            new UnknownHostException("Broken system behaviour for dns lookup of " + hostname);
        unknownHostException.initCause(e);
        throw unknownHostException;
      }
    }
  };
  /**
   * Returns the IP addresses of {@code hostname}, in the order they will be attempted by OkHttp. If
   * a connection to an address fails, OkHttp will retry the connection with the next address until
   * either a connection is made, the set of IP addresses is exhausted, or a limit is exceeded.
   */
  List<InetAddress> lookup(String hostname) throws UnknownHostException;
}

import okhttp3.Dns;
/**
 * File descripition:
 *
 * @author lp
 * @date 2019/4/16
 */
public class ApiDns implements Dns {
    @Override
    public List<InetAddress> lookup(String hostname) throws UnknownHostException {
        if (hostname == null) {
            throw new UnknownHostException("hostname == null");
        } else {
            try {
                List<InetAddress> mInetAddressesList = new ArrayList<>();
                InetAddress[] mInetAddresses = InetAddress.getAllByName(hostname);
                for (InetAddress address : mInetAddresses) {
                    if (address instanceof Inet4Address) {
                        mInetAddressesList.add(0, address);
                    } else {
                        mInetAddressesList.add(address);
                    }
                }
                return mInetAddressesList;
            } catch (NullPointerException var4) {
                UnknownHostException unknownHostException = new UnknownHostException("Broken system behaviour");
                unknownHostException.initCause(var4);
                throw unknownHostException;
            }
        }
    }
}

OkHttpClient.Builder httpClientBuilder = new OkHttpClient.Builder();
        ClearableCookieJar cookieJar =
                new PersistentCookieJar(new SetCookieCache(), new SharedPrefsCookiePersistor(AppUMS.mContent));
        httpClientBuilder
                .cookieJar(cookieJar)
                .addInterceptor(interceptor)
                .addInterceptor(new HeadUrlInterceptor())
                //设置请求超时时长
                .connectTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
                .writeTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
                .readTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS)
                .retryOnConnectionFailure(true)//错误重联
                .dns(new ApiDns());