Task(Mailbox mailbox, Flag flag) { this.mailbox = mailbox; this.flag    = flag; }
Task(Mailbox mailbox, Flag flag, int id) { this.mailbox = mailbox; this.flag    = flag; this.taskId = id; }
   Task(Mailbox mailbox, Flag flag)      {      this.mailbox = mailbox;      this.flag    = flag;      }