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Grouping by standardized categories

Now that you have standardized the categories of your electronics inventory, you would like to compute the quantity of each category. Merge the quantities into category sums.

Deze oefening maakt deel uit van de cursus

Cleaning Data in Java

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Oefeninstructies

  • Define an enum map to store the quantity of each ProductCategory in stockByCategory.
  • Merge the quantities into category sums in stockByCategory.

Praktische interactieve oefening

Probeer deze oefening eens door deze voorbeeldcode in te vullen.

public class ElectronicsCategoryExample {
    public enum ProductCategory {
        ELECTRONICS,
        HOME_APPLIANCES,
        UNCATEGORIZED;
    }

    public static void main(String[] args) {
    	Map categoryMap = new HashMap<>();
        categoryMap.put("Home Appliances", ProductCategory.HOME_APPLIANCES);
        categoryMap.put("home appliances", ProductCategory.HOME_APPLIANCES);
        categoryMap.put("HomeAppliances", ProductCategory.HOME_APPLIANCES);
        categoryMap.put("Electronics", ProductCategory.ELECTRONICS);
        categoryMap.put("electronics", ProductCategory.ELECTRONICS);
        categoryMap.put("Electronic", ProductCategory.ELECTRONICS);
        
        Map rawData = Map.of(
                "Home Appliances", 50,
                "home appliances", 25,
                "HomeAppliances", 15,
                "Electronics", 30,
                "electronics", 20,
                "Electronic", 10);

        // Define an enum map to store the quantity of each ProductCategory
        Map stockByCategory = new ____<>(____.class);

        // Merge the quantities into category sums
        rawData.forEach((raw, quantity) -> ____.____(categoryMap.get(raw), quantity, Integer::sum));

		System.out.println("Stock by category:");
        System.out.println(stockByCategory);
    }
}
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