HomeWork9(Работа с сетью)(3)(Вариант c регулярными выражениями)

Main.java

import java.io.BufferedReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {

    private static final Pattern urlPattern = Pattern.compile(
            "(?:^|[\\W])((ht|f)tp(s?):\\/\\/|www\\.)"
            + "(([\\w\\-]+\\.){1,}?([\\w\\-.~]+\\/?)*"
            + "[\\p{Alnum}.,%_=?&#\\-+()\\[\\]\\*$~@!:/{};']*)",
            Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);

    public static void main(String[] args) {

        String urlAdress = "https://prog.kiev.ua/forum/index.php/board,2.0.html";
        String text = getStringFromUrl(urlAdress);

        StringBuilder urlOut = new StringBuilder();
        Matcher matcher = urlPattern.matcher(text);
        while (matcher.find()) {
            int matchStart = matcher.start(1);
            int matchEnd = matcher.end();
            // now you have the offsets of a URL match
            String source, delete;
            source = matcher.group();
            delete = "\"";
            source = source.replace(delete, "");
            delete = "'";
            source = source.replace(delete, "");
//            System.out.println(source);
            urlOut.append(source).append(System.lineSeparator());
        }

        try (FileWriter writer = new FileWriter("text.txt")) {
            writer.write(urlOut.toString());
            writer.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static String getStringFromUrl(String urlAdress) { //получения HTML разметки страницы
        StringBuilder sb = new StringBuilder();
        try {
            URL url = new URL(urlAdress);
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream())); //InputStreamReader() -> может принимать второй параметр - это кодировка текста, если сервер передает информацию по другой кодировке и текст не читабельный
            String text = null;
            for (; (text = br.readLine()) != null;) {
                sb.append(text).append(System.lineSeparator());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return sb.toString();
    }

}