Creating Behavior with Methods
Attributes are the way to keep track of information about a class of objects, but they don't take any action. For a class to actually do the things it was created to do, you must create behavior. Behavior describes all of the different sections of a class that accomplish specific tasks. Each of these sections is called a method.
You have been using methods throughout your programs up to this point without knowing it, including one in particular: println(). This method displays text onscreen. Like variables, methods are used in connection with an object or a class. The name of the object or class is followed by a period and the name of the method, as in screen2D.drawString() or Integer.parseInt().
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