This is a simple Java-based Shopping Cart Price Calculator that allows you to calculate the total price of items in a shopping cart. It can handle different pricing rules for each item, including discounts for buying in bulk.
Create a PriceRegistry:
Map<String, BigDecimal> prices = new HashMap<>();
prices.put("Apple", new BigDecimal("0.35"));
prices.put("Banana", new BigDecimal("0.20"));
prices.put("Melon", new BigDecimal("0.50"));
prices.put("Lime", new BigDecimal("0.15"));
PriceRegistry priceRegistry = new MapPriceRegistry(prices);Create a CalculationRuleRegistry:
Map<String, CalculationRule> rules = new HashMap<>();
rules.put("Melon", new BulkDiscount(2,1)); // buy 2 pay for 1
rules.put("Lime", new BulkDiscount(3,2)); // buy 3 pay for 2
CalculationRuleRegistry calculationRuleRegistry = new MapCalculationRuleRegistry(rules);Create a ShoppingCartCalculator and calculate the total price:
ShoppingCartCalculator calculator = new DefaultShoppingCartCalculator(priceRegistry,ruleRegistry);
ShoppingCart cart = ShoppingCart.of("Apple", "Banana", "Apple", "Melon", "Melon", "Lime", "Lime", "Lime");
BigDecimal totalPrice = calculator.calculateTotalPrice(cart);./gradlew build