Request

import java.io.*;
import java.net.HttpURLConnection;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.URL;
import java.util.*;

public class Request implements Runnable{
    private String url;
    private String host;
    private int port;
    public static volatile boolean result = false;

    public static ArrayList<ProxyService> worked = new ArrayList<>();

    public Request(String host , int port , String url) {
        this.host = host;
        this.port = port;
        this.url = url;
    }

    @Override
    public void run() {
        Proxy proxy = new Proxy(Proxy.Type.HTTP , new InetSocketAddress(host ,port));
        try {
            HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection(proxy);
            connection.setReadTimeout(2000);
            connection.setConnectTimeout(2000);
            connection.setRequestMethod("GET");
            connection.connect();

            if (HttpURLConnection.HTTP_OK == connection.getResponseCode()) {
                System.out.println("Соединение установлено , прокси работает ");
                result = true;
            }
        }

        catch (IOException e) {
            System.out.println("Соединение не установлено , прокси не работает");
            result = false;
        }

        if (result) {
            worked.add(new ProxyService(host , port));
            try {
                PrintStream ps = new PrintStream("C:\\Users\\samsung\\Desktop\\a.txt");
                for (ProxyService p : worked) {
                    String host = p.getHost();
                    int port = p.getPort();
                    ps.println(p.getHost() + ":" + p.getPort());
                }
                ps.close();
            }

            catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}