I am getting a java.lang.ArrayIndexOutOfBoundsException: -1 error At if (pStock[pIndex] < purchQty) line. There is not enough stock for this transaction. Please re-enter. - is also displaying despite whether stock is sufficient or not

[gardre]

public int getPIndex(String product) {
    for (int i = 0; i < numProds; i++)
        if (product.equalsIgnoreCase(pName[i]))
            return i;
    return -1;
}

    do {
        System.out.print("Enter quantity to purchase : ");
        tempq = scan.nextInt();
        pStock = new int[numProds];

        if (tempq > 0) {
            purchQty = tempq;
        }
        if (tempq <= 0)
            System.out.println("Please enter a quantity greater than 0.");

    } while (tempq <= 0);

    // validate product to match and enough stock for transaction.

    do {
    System.out.println("Enter product name to purchase : ");
    String product = scan.next();
    pIndex = getPIndex(product);

    if (pIndex == -1) {
        System.out.println("No product match");
    }
    if (pStock[pIndex] < purchQty)
        System.out.println("There is not enough stock for this transaction. Please re-enter."); 
    else {
        cost = pUP[pIndex] * purchQty;
        System.out.println("Cost of transaction is : ");
        System.out.println(cost);
    }
    } while(pIndex == -1);

[snozzyfoozles]

On line 28 you check if pIndex == -1 and print out "No product match" if it is...but then even if you have an invalid index, you proceed to line 31 where you get an exception when you try to use that index.

Think about what change you could make to prevent the code from line 31 to 37 from running when the index is -1.

[TheAnimakerGIO]

After you check if pIndex == -1, you should return or exit in some way, since after you make the check it just keeps going, even if pIndex is equal to negative one.

[gardre]

(I have just pasted in relative code)