@Override public String toString(){
  return "[" + this.hour + ","+ getDayOfMonth()+ "/"+ getMonth()+ "/"+ getYear()+ "]";
}

@ Override public String toString ( ) { return "[" + this . hour + "," + getDayOfMonth ( ) + "/" + getMonth ( ) + "/" + getYear ( ) + "]" ; }
returns a string representation of this instance , for debugging purposes .
