You never declare "a" as a variable that could possibly be visible to the length method. It's only incarnation is as a parameter to the myString constructor and as such is visible within that and only that constructor. Please read up on variable scope and visibility in an introductory Java text or tutorial. This will explain all.
hello, i need to increase the length of my character array.i tred using ArrayUtils class which supports setSize method to set the size of a previously declared character array.But,i have no idea of how to import that class.i meant 'which package to use' for it. plz help me out of this thanks