Adapter

// Third-party code. We cannot rewrite it — it has run in production for years.class LegacyGateway {  sendPaymentXml(xml) {    return '<response><status>OK</status></response>';  }} // The interface the client knows how to use.class Payment {  pay(amount) { throw new Error('abstraktná metóda'); }} class GatewayAdapter extends Payment {  constructor(gateway) {    super();    this.gateway = gateway;  }   pay(amount) {    const xml = '<payment><amount>' + amount + '</amount></payment>';    const response = this.gateway.sendPaymentXml(xml);    return { status: response.includes('<status>OK</status>') ? 'ok' : 'error' };  }} const payment = new GatewayAdapter(new LegacyGateway());payment.pay(25);   // { status: 'ok' }