How do I know if I can convert a String value to an int value or not?

Question

Hi,
I want to know how to make the judgment that if I can convert a String value to an int value or not? Assume that I don't know the String is number or letters
Thank you

Answer 1

Encephalopathic wrote
Again, why?One of the problems (have been dued) in my codelab asks us to write a class as follow
Write a class definition of a class named 'Value' with the following:
a constructor accepting a single integer paramter
a constructor with no parameters
a method 'setVal' that accepts a single parameter,
a boolean method, 'wasModified' that returns true if setVal was ever called for the object.
a method 'getVal' that returns an integer value as follows: if setVal has ever been called, it getVal returns the last value passed to setVal. Otherwise if the "single int parameter" constructor was used to create the object, getVal returns the value passed to that constructor. Otherwise getVal returns 0.
The setVal(int y) returns nothing, so how do I know whether it has been called or not?
Thank you