Trouble implementing Shoe Inventory program in Java

Question

I am trying to implement an Inventory program for shoes. What I am trying to do is give each shoe an id (productId) and a quantity of shoes that are in stock (ammountToPick). I want to be able to ask the user running the program to enter a shoe id to get the amount of that type of shoe that are left in stock (ammountToPick). My current problem with my program is that it is not returning anything and just keeps printing "invalid product id".

I have provided my code below:

public class Product {
  private String productId = "";
  private int ammountToPick = 0;
  private int ammountToRestock = 0;

  public Product (String productId, int ammountToPick){

   this.productId = productId;
   this.ammountToPick = ammountToPick;

  }

  public String getProductId() {
    return productId;
  }

  public int getAmmountToPick() {
    return ammountToPick;
  }

}

public class Shoes extends Product{
  public Shoes(String productId, int ammountToPick){
   super(productId, ammountToPick); 

  }


}

import java.util.Scanner;  
public class Inventory
{
    private static String productId = "";
  private int ammountToPick = 0;
  private int ammountToRestock = 0;
  public static final int MAX_ITEMS = 999999;
  private static Product product [] = new Shoes[MAX_ITEMS];

  public static void main (String args[]){

  buildInventory();
  getInventory();
}

public static void buildInventory(){

product[1] = new Shoes("shoe101", 19);
product[2] = new Shoes("shoe200", 1);
product[3] = new Shoes("shoe420", 9);
}

public static void getInventory() {
  Scanner input = new Scanner(System.in);
  System.out.println("Enter the product id of the product you would like to pick: ");
  String userinput = input.nextLine();
  if(userinput.equals(productId)) {
    System.out.println("there are" + product[1].getAmmountToPick() +"left");
  }
  else {

   System.out.println("invalid product id ");
  }
}
}

You never initialize productId to anything but an empty string, so it's always an empty string. — Malphrush
– Malphrush, Commented Jul 18, 2017 at 17:42

ControlAltDel · Accepted Answer · 2017-07-18 18:40:24Z

1

if(userinput.equals(productId)) {
    System.out.println("there are" + product[1].getAmmountToPick() +"left");
  }
else {

On the first line, you problem is that productId is set to an empty string at the top of the class. It should actually work if you just hit enter without entering an actual productId and userinput is "". But to make this work the way you want, get rid of your productId variable and check if userinput matches a productId of one of the items in your array

you need to do

userinput = ...; //this part is fine
for (Product p : products) {
  if (userinput.equals(p.getProductId())) {
    System.out.println('there are ' + p.getAmmountToPick() + " left");
  }
}

edited Jul 18, 2017 at 18:40

answered Jul 18, 2017 at 17:43

ControlAltDel

35.3k10 gold badges60 silver badges86 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

chris2656 Over a year ago

awesome Thank you so much !

user6629913 · Accepted Answer · 2017-07-18 18:48:56Z

0

Both the Product and Inventory classes have productId member variables. You're comparing userInput to the private static productIdin the Inventory class, which is an empty string.

I think you should be iterating through your inventory array looking for a match to the productId of a Product.

Here's one way to do it with an enhanced loop and no new methods:

boolean found = false;
for (final Product aProduct: product) {
    if(userInput.equals(aProduct.getProductId())) {
        System.out.println("there are" + aProduct.getAmmountToPick() +"left");
        found = true;
        break;
    }
}
if(!found) {
    System.out.println("invalid product id ");
}

I'd rename the product member variable to products so its intent is clearer. It would make the code above clearer as well.

Inventory, in the way you're using it, needs no productId. It should be deleted.

edited Jul 18, 2017 at 18:48

answered Jul 18, 2017 at 17:48

user6629913

1822 silver badges14 bronze badges

3 Comments

chris2656 Over a year ago

How would I go about iterating through the inventory array?

chris2656 Over a year ago

Something like this ? public static void getInventory() { Scanner input = new Scanner(System.in); for(int i = 0; i < product.length; i++) { System.out.println("Enter the product id of the product you would like to pick: "); String userinput = input.nextLine(); if(userinput.equals(product)) { System.out.println("there are" + product[i].getAmmountToPick() +"left"); } } }

user6629913 Over a year ago

Your solution doesn't take into account the negative outcome, where no match is found.

Collectives™ on Stack Overflow

Trouble implementing Shoe Inventory program in Java

2 Answers 2

1 Comment

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related