การสร้าง category mapping

public class ElectronicsCategoryExample {
	// Create an enum called ProductCategory
    public ____ ____ {
        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);
        
        System.out.println("Electronics category:");
        System.out.println(categoryMap.get("Electronics"));
        
        // Look up an unknown category
        ProductCategory unknownCategory = ____.____(
    			"Mystery category", ProductCategory.UNCATEGORIZED);
                
        System.out.println("\nMystery category:");
        System.out.println(unknownCategory);
        
        // Create an unmodifiable map
        Map immutableMap = ____.____(categoryMap);
        
        System.out.println("\nAttempting to modify immutable map:");
        try {
            immutableMap.put("new", ProductCategory.ELECTRONICS);
        } catch (UnsupportedOperationException e) {
            System.out.println("Cannot modify immutable map");
        }
    }
}