Here is the class definition, again:
class CheckingAccount
{
  // instance variables
  String accountNumber;
  String accountHolder;
  int    balance;
  //constructors
  . . . .
  // methods
}
Let us work on a method that will return the current balance. When it is called, it will not alter any data in a checking account object, but merely return the current balance.
Write the first line (the header) of the definition for this method. The method will not use any parameters. You will have to think of a name for the method.