import com.qiniu.android.dns.DnsManager; //导入依赖的package包/类
private static DnsManager initDns(Builder builder) {
    DnsManager d = builder.dns;
    builder.up.addIpToDns(d);
    if (builder.upBackup != null) {
        builder.upBackup.addIpToDns(d);
    }
    return d;
}
 

import com.qiniu.android.dns.DnsManager; //导入依赖的package包/类
public void addIpToDns(DnsManager d) {
    for (String ip : this.backupIps) {
        d.putHosts(this.address.getHost(), ip);
    }
}
 

import com.qiniu.android.dns.DnsManager; //导入依赖的package包/类
public CommonImageDownloader(Context context, int connectTimeout, int readTimeout, DnsManager dns) {
    super(context, connectTimeout, readTimeout);
    this.dns = dns;
}