[JAVA] 클래스/메서드 호출 코드 리팩토링

📋 기존 코드

package class1.ex;

public class ProductOrderMain {

    public static void main(String[] args) {
        ProductOrder[] orders = new ProductOrder[3];

        ProductOrder order1 = new ProductOrder();
        order1.productName = "두부";
        order1.price = 2000;
        order1.quantity = 2;
        orders[0] = order1;

        ProductOrder order2 = new ProductOrder();
        order2.productName = "김치";
        order2.price = 5000;
        order2.quantity = 1;
        orders[1] = order2;

        ProductOrder order3 = new ProductOrder();
        order3.productName = "계란";
        order3.price = 4000;
        order3.quantity = 30;
        orders[2] = order3;

        int totalAmount = 0;
        for (ProductOrder order : orders) {
            System.out.println("상품명: "+order.productName + "가격: "+order.price+"수량: " + order.quantity);
            totalAmount += order.price * order.quantity;
        }

        System.out.println("총 결제 금액: " + totalAmount);
    }
}

 

이런식으로 생성자를 만들어가며 객체를 생성하는 코드가 있다고 하자.

불필요하게 반복되는 부분이 많다. 

이걸 메서드를 활용하여 리팩토링 해보자.

 

 

📋 코드 리팩토링 

package ref.ex;
public class ProductOrderMain2 {
    public static void main(String[] args) {
        ProductOrder[] orders = new ProductOrder[3];

        orders[0] = createOrder("두부",2000,2);
        orders[1] = createOrder("김치",5000,1);
        orders[2] = createOrder("계란",4000,3);

        printOrders(orders);
        int totalAmount = getTotalAmount(orders);
        System.out.println("총 결제 금액: " + totalAmount);
    }

    static ProductOrder createOrder(String productName, int price,int quantity){
        ProductOrder order = new ProductOrder();
        order.productName = productName;
        order.price = price;
        order.quantity = quantity;
        return order; // order반환
    }

    static void printOrders(ProductOrder[] orders){
        for (ProductOrder order : orders) {
            System.out.println("상품명: "+order.productName + "가격: "+order.price+"수량: " + order.quantity);

        }
    }

    static int getTotalAmount(ProductOrder[] orders){
        int totalAmount = 0;
        for (ProductOrder order : orders) {
            totalAmount += order.price * order.quantity;
        }
        return totalAmount;
    }
}

 

- createOrder(String productName,int price,int quantity)를 생성

- printOrders(ProductOrder[] orders) 생성

- getTotalAmount(ProductOrder[] orders) 생성 

 

📋 입력값을 받도록 수정된 코드

package ref.ex;

import java.util.Scanner;

public class ProductOrderMain3 {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("입력할 주문의 개수를 입력하세요: ");
        int n = scanner.nextInt();
        scanner.nextLine();

        ProductOrder[] orders = new ProductOrder[n];
        for(int i=0; i<orders.length;i++){
            System.out.println((i+1)+"번째 주문 정보를 입력하세요.");

            System.out.println("상품명: ");
            String productName = scanner.nextLine();

            System.out.println("가격: ");
            int price = scanner.nextInt();

            System.out.println("수량: ");
            int quantity = scanner.nextInt();
            scanner.nextLine();

            orders[i] = createOrder(productName,price,quantity);

        }

        printOrders(orders);
        int totalAmount = getTotalAmount(orders);
        System.out.println("총 결제 금액: " + totalAmount);
    }

    static ProductOrder createOrder(String productName, int price,int quantity){
        ProductOrder order = new ProductOrder();
        order.productName = productName;
        order.price = price;
        order.quantity = quantity;
        return order; // order반환
    }

    static void printOrders(ProductOrder[] orders){
        for (ProductOrder order : orders) {
            System.out.println("상품명: "+order.productName + "가격: "+order.price+"수량: " + order.quantity);

        }
    }

    static int getTotalAmount(ProductOrder[] orders){
        int totalAmount = 0;
        for (ProductOrder order : orders) {
            totalAmount += order.price * order.quantity;
        }
        return totalAmount;
    }
}

 

Scanner를 사용하여 입력받는 값을 저장하여 메서드를 활용해서 프로그램에 입출력 할 수 있도록 하는 코드이다.