In my code, I have 2 methods. In my first method, I completely rely on StringBuilder and it's reverse() method. This seems to work. However, in my second method, I don't get anything returned. Why is this?
I guess you meant i-- rather than i++ at for update.
Why do you think you need to String variables? You don't need two String variables, only one is enough.
I think you don't need to declare String variables as static unless there is a valid reason it be static, either declare it as an instance ( non-static ) variable may be with private modifier? then you can initialize it using constructor or you can declare and initialise String variable as local variable in main method.