import java.io.*;

public class WindowsUtils {
  private static final String REGQUERY_UTIL = "reg query ";
  private static final String REGSTR_TOKEN = "REG_SZ";
  private static final String DESKTOP_FOLDER_CMD = REGQUERY_UTIL +
  "\"HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\"
   + "Explorer\\Shell Folders\" /v DESKTOP";

  private WindowsUtils() {}

  public static String getCurrentUserDesktopPath() {
    try {
      Process process = Runtime.getRuntime().exec(DESKTOP_FOLDER_CMD);
      StreamReader reader = new StreamReader(process.getInputStream());

      reader.start();
      process.waitFor();
      reader.join();

      String result = reader.getResult();
      int p = result.indexOf(REGSTR_TOKEN);

      if (p == -1)
         return null;

      return result.substring(p + REGSTR_TOKEN.length()).trim();
    }
    catch (Exception e) {
      return null;
    }
  }


  /**
   * @param args
   */
  public static void main(String[] args) {
    System.out.println("Desktop directory : "
       + getCurrentUserDesktopPath());

  }

  static class StreamReader extends Thread {
    private InputStream is;
    private StringWriter sw;

    StreamReader(InputStream is) {
      this.is = is;
      sw = new StringWriter();
    }

    public void run() {
      try {
        int c;
        while ((c = is.read()) != -1)
          sw.write(c);
        }
        catch (IOException e) { ; }
      }

    String getResult() {
      return sw.toString();
    }
  }
}