13. Functional Programming with Lambda Expressions

Activity 1: Modifying Immutable Lists

Solution

1. Write an application which modifies the ShoppingCart class found in Exercise 2 to allow for removing items from the cart.

           public ShoppingCart removeItem(ShoppingItem item) {
              Map<String, Integer> newList = new HashMap<>(mShoppingList);
               int value = 0;
               if (newList.containsKey(item.name)) {
                   value = newList.get(item.name);
               }
               if (value > 0) {
         ...