Cast a Null String into Integer

Question

Is there any way to cast a null to Integer. The null is actually a String, which i am passing in my service layer that accepts it as an Integer. So, whenever i try to cast a null String to Integer, it throws me an exception. But i have to cast the null into Integer.

Answer 1

You cannot cast from String to Integer. However, if you are trying to convert string into integer and if you have to provide an implementation for handling null Strings, take a look at this code snippet:

String str = "...";
// suppose str becomes null after some operation(s).
int number = 0;
try
{
    if(str != null)
      number = Integer.parseInt(str);
}
catch (NumberFormatException e)
{
    number = 0;
}

Answer 2

If you're using apache commons, there is an helper method that does the trick:

NumberUtils.createInteger(myString)

As said in the documentation:

"convert a String to a Integer, handling hex and octal notations; returns null if the string is null; throws NumberFormatException if the value cannot be converted.