Code Correction and Improvement for Shop Management Project

[isaiasgh]

Hi,

I've reviewed the code for your shop management project and identified some areas that could be improved to enhance efficiency and fix certain errors. Below, I outline the suggested changes:

Code Changes

1. Correct Errors in List Handling: In the Shop class, ensure to properly initialize the productList and operationsList in the constructor.
2. Method Implementation: Implement the enlistProduct() and addOperation() methods in the Shop class to correctly add products and operations to their respective lists.
3. Inheritance Hierarchy and Interface Usage: Clearly define the interfaces and their implementations (TransactionalOperation and ProductOperation).

Modified Code

TransactionalOperation Interface:

public interface TransactionalOperation {
    void execute();
}

ProductOperation Interface:

public interface ProductOperation {
    void apply(Product product);
}

Shop Class

import java.util.ArrayList;
import java.util.List;

public class Shop {
    private List<Product> productList;
    private List<TransactionalOperation> operationsList;

    public Shop() {
        this.productList = new ArrayList<>();
        this.operationsList = new ArrayList<>();
    }

    public void enlistProduct(Product product) {
        this.productList.add(product);
    }

    public void addOperation(TransactionalOperation operation) {
        this.operationsList.add(operation);
    }
}

Product Class

public class Product {
    private String name;
    private double price;
    private int quantity;

    public Product(String name, double price, int quantity) {
        this.name = name;
        this.price = price;
        this.quantity = quantity;
    }

    // Getters and Setters
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public double getPrice() { return price; }
    public void setPrice(double price) { this.price = price; }
    public int getQuantity() { return quantity; }
    public void setQuantity(int quantity) { this.quantity = quantity; }
}

Purchase Class

public class Purchase implements TransactionalOperation, ProductOperation {
    private Product product;
    private int quantity;

    public Purchase(Product product, int quantity) {
        this.product = product;
        this.quantity = quantity;
    }

    @Override
    public void execute() {
        apply(product);
    }

    @Override
    public void apply(Product product) {
        product.setQuantity(product.getQuantity() + quantity);
    }
}

Sale Class

public class Sale implements TransactionalOperation, ProductOperation {
    private Product product;
    private int quantity;

    public Sale(Product product, int quantity) {
        this.product = product;
        this.quantity = quantity;
    }

    @Override
    public void execute() {
        apply(product);
    }

    @Override
    public void apply(Product product) {
        product.setQuantity(product.getQuantity() - quantity);
    }
}

Damage Class

public class Damage implements TransactionalOperation, ProductOperation {
    private Product product;
    private int quantity;

    public Damage(Product product, int quantity) {
        this.product = product;
        this.quantity = quantity;
    }

    @Override
    public void execute() {
        apply(product);
    }

    @Override
    public void apply(Product product) {
        product.setQuantity(product.getQuantity() - quantity);
    }
}

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