Change border color from blue to green of JFrame

[altu57]

How to change border color of JFRame

[Webuser]

Move in this field :)

import javax.swing.*;   
import java.awt.*;   
class Testing   
{   
  public void buildGUI()   
  {   
    JFrame f = new JFrame("JFrame");   
    f.setUndecorated(true);   
    f.getRootPane().setWindowDecorationStyle(JRootPane.WARNING_DIALOG);   
    f.setSize(400,300);   
    f.setLocationRelativeTo(null);   
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);   
    f.setVisible(true);   
  }   
  public static void main(String[] args)   
  {   
    SwingUtilities.invokeLater(new Runnable(){   
      public void run(){   
        new Testing().buildGUI();   
      }   
    });   
  }   
}