RandomCharacter

import javax.swing.JFrame;

public class RandomCharactersTest {

    public static void main(String[] args)
    {
        RandomCharacters randomCharacters = new RandomCharacters();

        randomCharacters.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        randomCharacters.setSize(200,200);
        randomCharacters.setVisible(true);
    }
}
/////////////////////

import java.awt.Color;
import java.awt.FlowLayout;
import java.security.SecureRandom;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;

public class RandomCharacters extends JFrame
{

    private JLabel randChar;
    private JTextField tf;

    private final JButton button;

    public RandomCharacters()
    {
        super("Random Characters");
        setLayout(new FlowLayout());

        tf = new JTextField(15);

        randChar = new JLabel("fire");
        add(randChar);

        button = new JButton("hi");
        add(button);

        while(true)
        {
            paintComponent();
        }
    }

    public void paintComponent()
    {
        SecureRandom r = new SecureRandom();

        switch(r.nextInt(7))
        {
        case 0: randChar.setForeground(Color.RED);
        break; //RED
        case 1: randChar.setForeground(Color.YELLOW);
        break; //YELLOW
        case 2: randChar.setForeground(Color.BLUE);
        break; //BLUE
        case 3: randChar.setForeground(Color.GREEN);
        break; //GREEN
        case 4: randChar.setForeground(Color.CYAN);
        break; //CYAN
        case 5: randChar.setForeground(Color.PINK);
        break; //PINK
        case 6: randChar.setForeground(Color.BLACK);
        //BLACK
        }
    }
}