Getting NumberFormatException using Integer.parseInt()

Question

Why am i getting NumberFormatException here? I entered code value as 1. Unable to understand why i got this exception

I used InputMismatchException because earlier i had used nextInt() method of Scanner class, instead of Integer.parseInt().Also earlier i had taken code of type Int instead of String, but now modified it.

I think it has to do with sc.nextLine() , but not using it skips the user input during runtime.

  public void searchItem() {

    String code = "";
    NewItem foundItem;
    String searchdisString = "";
    int finalCode = 0;

    if (ItemList != null && ItemList.size() > 0) {
        System.out.println("Enter Item code:");
        try {
            code = sc.nextLine();
            sc.nextLine();

            // Line 142 below
            finalCode = Integer.parseInt(code);
        } catch (InputMismatchException e) {
            System.out.println("Please enter a valid code.");
            return;
        }
        foundItem = search(code);
        if (foundItem == null) {
            System.out.println("Item not found");
            return;
        }

        else {
            System.out.println(foundItem.toString());
        }
    } else {
        System.out.println("No items to search. Please go to #3 to add items first.\nThank you.");
    }
}

Output :

  New Shop for Items created.
-----ITEM------
1. Display all items
2. Search items
3. Add items to list
4. Add items to cart
5. Display cart
6. Issue item
7. Exit
Choice:
3
Enter Item code:
1
Item name : 
apple
apple 
Rate : 
20
Quantity : 
30
1. Display all items
2. Search items
3. Add items to list
4. Add items to cart
5. Display cart
6. Issue item
7. Exit
Choice:
2
Enter Item code:
1

Error:

Exception in thread "main" java.lang.NumberFormatException: For input string: "" at
java.lang.NumberFormatException.forInputString(NumberFormatException.java:65) at java.lang.Integer.parseInt(Integer.java:504) at java.lang.Integer.parseInt(Integer.java:527) at NewShop.searchItem(NewShop.java:142) at NewShoppingCart.main(NewShoppingCart.java:45)

EDIT :

if(ItemList!=null&&ItemList.size()>0)
      {
        System.out.println("Enter Item code:");
        try{
            code = sc.nextLine();

            finalCode = Integer.parseInt(code.trim());
           }
        catch(InputMismatchException e){
         System.out.println("Please enter a valid code.");
         return;
        }

Output :

New Shop for Items created.
-----ITEM------
1. Display all items
2. Search items
3. Add items to list
4. Add items to cart
5. Display cart
6. Issue item
7. Exit
Choice:
3   
Enter Item code:
1
Item name : 
APPLE
20
APPLE 
Rate : 
30
Quantity : 
20
1. Display all items
2. Search items
3. Add items to list
4. Add items to cart
5. Display cart
6. Issue item
7. Exit
Choice:
2
Enter Item code:
Exception in thread "main" java.lang.NumberFormatException: For input   string: ""
 at    java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:504)
at java.lang.Integer.parseInt(Integer.java:527)
at NewShop.searchItem(NewShop.java:141)
at NewShoppingCart.main(NewShoppingCart.java:45)

Answer 1

code = sc.nextLine();
sc.nextLine(); // reading extra line

// Line 142 below
finalCode = Integer.parseInt(code);

You are reading an extra line which is empty. Just remove it and it should work.

sc.nextLine(); // reading extra line
code = sc.nextLine();
// Line 142 below
finalCode = Integer.parseInt(code);

Answer 2

Might be, it having some blank space.

try this: finalCode = Integer.parseInt(code.trim());