Java: Inventory Management

Java OOP: Exercise-13 with Solution

Write a Java program to create a class called "Inventory" with a collection of products and methods to add and remove products, and to check for low inventory.

Sample Solution:

Java Code:

// Product.java
// Define the Product class
public class Product {
  // Private field to store the name of the product
  private String name;
  // Private field to store the quantity of the product
  private int quantity;

  // Constructor to initialize the name and quantity of the product
  public Product(String name, int quantity) {
    // Assign the name parameter to the name field
    this.name = name;
    // Assign the quantity parameter to the quantity field
    this.quantity = quantity;
  }

  // Getter method for the name field
  public String getName() {
    // Return the value of the name field
    return name;
  }

  // Setter method for the name field
  public void setName(String name) {
    // Assign the name parameter to the name field
    this.name = name;
  }

  // Getter method for the quantity field
  public int getQuantity() {
    // Return the value of the quantity field
    return quantity;
  }

  // Setter method for the quantity field
  public void setQuantity(int quantity) {
    // Assign the quantity parameter to the quantity field
    this.quantity = quantity;
  }
}

In the above code, we create a class called "Product" with two private attributes, "name" and "quantity". We also create a constructor to initialize these attributes and getter and setter methods to access and modify them.

// Inventory.java
// Import the ArrayList class from the java.util package
import java.util.ArrayList;

// Define the Inventory class
public class Inventory {
  // Private field to store a list of Product objects
  private ArrayList<Product> products;

  // Constructor to initialize the products field
  public Inventory() {
    // Create a new ArrayList to hold Product objects
    products = new ArrayList<Product>();
  }

  // Method to add a Product to the products list
  public void addProduct(Product product) {
    // Add the specified product to the products list
    products.add(product);
  }

  // Method to remove a Product from the products list
  public void removeProduct(Product product) {
    // Remove the specified product from the products list
    products.remove(product);
  }

  // Method to check for low inventory products
  public void checkLowInventory() {
    // Iterate through the list of products
    for (Product product : products) {
      // Check if the product quantity is less than or equal to 100
      if (product.getQuantity() <= 100) {
        // Print a message indicating the product is running low on inventory
        System.out.println(product.getName() + " is running low on inventory. Current quantity: " + product.getQuantity());
      }
    }
  }
}

Here we create a class called "Inventory" with a private attribute "products", which is an ArrayList of Product objects. We also create a constructor to initialize this attribute as an empty list and methods to add and remove products from the list. Additionally, we create a method called "checkLowInventory()" to check for low inventory levels in the products list.

// Main.java
// Define the Main class
public class Main {
  // Main method, entry point of the program
  public static void main(String[] args) {
    // Create a new instance of the Inventory class
    Inventory inventory = new Inventory();
    
    // Create new Product objects with name and quantity
    Product product1 = new Product("LED TV", 200);
    Product product2 = new Product("Mobile", 80);
    Product product3 = new Product("Tablet", 50);
    
    // Print a message indicating products are being added to the inventory
    System.out.println("Add three products in inventory:");
    
    // Add the products to the inventory
    inventory.addProduct(product1);
    inventory.addProduct(product2);
    inventory.addProduct(product3);
    
    // Print a message indicating low inventory check
    System.out.println("\nCheck low inventory:");
    
    // Check and print products with low inventory
    inventory.checkLowInventory();
    
    // Print a message indicating a product is being removed from the inventory
    System.out.println("\nRemove Tablet from the inventory!");
    
    // Remove the Tablet product from the inventory
    inventory.removeProduct(product3);
    
    // Print a message indicating another low inventory check
    System.out.println("\nAgain check low inventory:");
    
    // Check and print products with low inventory again
    inventory.checkLowInventory();
  }
}

In the "Main" class, we create an instance of the Inventory class and add three Product objects to the list. We then call the "checkLowInventory()" method to check for low inventory levels. Next, we remove one of the products from the list and call the "checkLowInventory()" method again to see if there are any other low inventory levels.

Sample Output:

Add three products in inventory:

Check low inventory:
Mobile is running low on inventory. Current quantity: 80
Tablet is running low on inventory. Current quantity: 50

Remove Tablet from the inventory!

Again check low inventory:
Mobile is running low on inventory. Current quantity: 80

Flowchart:

Java Code Editor:

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