JavaScript Design Patterns for Coding Interviews/

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Challenge: Solution Review

Challenge: Solution Review

This lesson will explain the solution to the problem from the previous coding challenge.

We'll cover the following...

Solution #

Node.js
class Auctioneer
{
    constructor(){
        this.bidderList = []
    }
    
    announceNewBidderPrice()
    {
        this.notifyBidders();
    }
     
    registerBidder(bidder)
    {
        this.bidderList.push(bidder);
    }
    
    notifyBidders()
    {
        this.bidderList.forEach(bidder => bidder.update())
    }
}
class Bidder 
{
    constructor(name){
        this.name = name
        this.bidPrice = null
    }
    
    update()
    {
        console.log(`${this.name} is offering ${this.bidPrice} dollars`);
        if (this.bidPrice > 500)
        {
            console.log(`Sold to ${this.name}`);
        }
    }
        
    giveNewPrice(price)
    {
        this.bidPrice = price;
    }
}
auctioner = new Auctioneer();
bidder1 = new Bidder("Ross");
auctioner.registerBidder(bidder1);
bidder2 = new Bidder("Joey");
auctioner.registerBidder(bidder2);
bidder1.giveNewPrice(200);
bidder2.giveNewPrice(350);
auctioner.announceNewBidderPrice()
bidder1.giveNewPrice(400);
bidder2.giveNewPrice(550);
auctioner.announceNewBidderPrice()

Explanation

In this example, we have the subject class Auctioneer that stores the list of all bidders to whom it announces the bidding prices.

class Auctioneer
{
    constructor(){
        this.bidderList = []
    }
    //code...
}

The constructor initializes the list bidderList that stores all the bidders participating in the auction. ...