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nchDev-js/chain-of-responsibility.js

Created February 20, 2021 19:05
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Design Patterns / BEHAVIORAL
Raw
chain-of-responsibility.js
class Account {
pay(orderPrice) {
if (this.canPay(orderPrice)) {
console.log(`Paid ${orderPrice} using ${this.name}`);
} else if (this.incomer) {
console.log(`Cannot pay using ${this.name}`);
this.incomer.pay(orderPrice);
} else {
console.log("Unfortunately, not enough money");
}
}
canPay(amount) {
return this.balance >= amount;
}
setNext(account) {
this.incomer = account;
}
}
class Master extends Account {
constructor(balance) {
super();
this.name = "Master Card";
this.balance = balance;
}
}
class Paypal extends Account {
constructor(balance) {
super();
this.name = "Paypal";
this.balance = balance;
}
}
class Qiwi extends Account {
constructor(balance) {
super();
this.name = "Qiwi";
this.balance = balance;
}
}
Raw
command.js
class Driver {
constructor(command) {
this.command = command;
}
execute() {
this.command.execute();
}
}
class Engine {
constructor() {
this.state = false;
}
on() {
this.state = true;
}
off() {
this.state = false;
}
}
class OnStartCommand {
constructor(engine) {
this.engine = engine;
}
execute() {
this.engine.on();
}
}
class onSwitchOffCommand {
constructor(engine) {
this.engine = engine;
}
execute() {
this.engine.off();
}
}
Raw
iterator.js
class ArrayIterator {
constructor(el) {
this.index = 0;
this.elements = el;
}
next() {
return this.elements[this.index++];
}
hasNext() {
return this.index < this.elements.length;
}
}
class ObjectIterator {
constructor(el) {
this.index = 0;
(this.keys = Object.keys(el)), (this.elements = el);
}
next() {
return this.elements[this.keys[this.index++]];
}
hasNext() {
return this.index < this.keys.length;
}
}
Raw
mediator.js
class OfficialDealer {
constructor() {
this.customers = [];
}
orderAuto(customer, auto, info) {
const name = customer.getName();
console.log(`Order name: ${name}. Order auto is ${auto}`);
console.log(`Additional info: ${info}`);
this.addToCustomersList(name);
}
addToCustomersList(name) {
this.customers.push(name);
}
getCustomerList() {
return this.customers;
}
};
class Customer {
constructor(name, dealerMediator) {
this.name = name;
this.dealerMediator = dealerMediator;
}
getName() {
return this.name;
}
makeOrder(auto, info) {
this.dealerMediator.orderAuto(this, auto, info)
}
};
Raw
memento.js
class Memento {
constructor(value) {
this.value = value;
}
}
const creator = {
save: (val) => new Memento(val),
restore: (memento) => memento.value,
};
class Caretaker {
constructor() {
this.values = [];
}
addMemento(memento) {
this.values.push(memento);
}
getMemento(index) {
return this.values[index];
}
}
Raw
observer.js
class AutoNews {
constructor() {
this.news = "";
this.actions = [];
}
setNews(text) {
this.news = text;
this.notifyAll();
}
notifyAll() {
return this.actions.forEach((subs) => subs.inform(this));
}
register(observer) {
this.actions.push(observer);
}
unregister(observer) {
this.actions = this.actions.filter((el) => !(el instanceof observer));
}
}
class Jack {
inform(message) {
console.log(`Jack has been informed about: ${message.news}`);
}
}
class Max {
inform(message) {
console.log(`Max has been informed about: ${message.news}`);
}
}
Raw
state.js
class OrderStatus {
constructor(name, nextStatus) {
this.name = name;
this.nextStatus = nextStatus;
}
next() {
return new this.nextStatus();
}
}
class WaitingForPayment extends OrderStatus {
constructor() {
super("waitingForPayment", Shipping);
}
}
class Shipping extends OrderStatus {
constructor() {
super("shipping", Delivered);
}
}
class Delivered extends OrderStatus {
constructor() {
super("delivered", Delivered);
}
}
class Order {
constructor() {
this.state = new WaitingForPayment();
}
nextState() {
this.state = this.state.next();
}
}
Raw
strategy.js
function baseStrategy(amount) {
return amount;
};
function premiumStrategy(amount) {
return amount * 0.85;
};
function platinumStrategy(amount) {
return amount * 0.65;
};
class AutoCart {
constructor(discount) {
this.discount = discount;
this.amount = 0;
}
checkout() {
return this.discount(this.amount);
}
setAmount(amount) {
this.amount = amount;
}
};
Raw
template.js
class Builder {
build() {
this.addEngine();
this.installChassis();
this.addElectronic();
this.collectAccessories();
}
};
class TeslaBuilder extends Builder {
addEngine() {
console.log('Add Electronic Engine');
}
installChassis() {
console.log('Install Tesla chassis');
}
addElectronic() {
console.log('Add special electronic');
}
collectAccessories() {
console.log('Collect Accessories');
}
}
class BmwBuilder extends Builder {
addEngine() {
console.log('Add BMW Engine');
}
installChassis() {
console.log('Install BMW chassis');
}
addElectronic() {
console.log('Add electronic');
}
collectAccessories() {
console.log('Collect Accessories');
}
}
Raw
visitor.js
class Auto {
accept(visitor) {
visitor(this);
}
}
class Tesla extends Auto {
info() {
return "It is a Tesla car!";
}
}
class Bmw extends Auto {
info() {
return "It is a BMW car!";
}
}
class Audi extends Auto {
info() {
return "It is an Audi car!";
}
}
function exportVisitor(auto) {
if (auto instanceof Tesla)
auto.export = console.log(`Exported data: ${auto.info()}`);
if (auto instanceof Bmw)
auto.export = console.log(`Exported data: ${auto.info()}`);
if (auto instanceof Audi)
auto.export = console.log(`Exported data: ${auto.info()}`);
}
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