private void setRandomColor() {
    Random estrattore = new Random();
    int estratto = estrattore.nextInt(7);
    switch (estratto) {
        case 0:
            jLabel4.setForeground(Color.BLACK);
            break;
        case 1:
            jLabel4.setForeground(Color.BLUE);
            break;        
        case 2:
            jLabel4.setForeground(Color.GRAY);
            break;        
        case 3:
            jLabel4.setForeground(Color.MAGENTA);
            break;
        case 4:
            jLabel4.setForeground(Color.ORANGE);
            break;
        case 5:
            jLabel4.setForeground(Color.PINK);
            break;
        case 6:
            jLabel4.setForeground(Color.RED);
            break;        
    }
}