#中介者模式(Mediator)

class User {
  constructor(name, age) {
    this.name = name;
    this.age = age;
  }
  sendMessage(target, message) {
    target.addMessage(this.name, message);
  }
}

class ChatRoom {
  constructor(crname) {
    this.crname = crname;
    this.message = [];
  }
  addMessage(name, message) {
    this.message.unshift({ name, message });
  }
  showMessage() {
    return this.message;
  }
}
export { User, ChatRoom };

let user1 = new User("julong", "23");
let user2 = new User("dao", "32");
let devRoom = new ChatRoom("devroom");
user1.sendMessage(devRoom, "hello");
user1.sendMessage(devRoom, "hi~  what");
user2.sendMessage(devRoom, "halou ju long ");
devRoom.showMessage();