Lesson 1:

Three big concepts:

An object is an entity that contains  data and its own methods for manipulating that data.  
A class is a collection of objects.  The class  definition provides a prototype for all of its objects. 
A class can inherit all or most of its  definition from another class.   In Java we say that a class  extends another and objects in the extended class will inherit the data and methods from the original class plus will probably have additional data and/or methods. 

1. Creating an Object 
   The constructor for a class has the same name as the class.  We create an object as follows:
   ClassName objectName = new ClassName(argument list);
   
2. Using an Object
    We use the methods of an object as follows:
   objectName.methodName(actual arguments);

Try this:

1. Look up the Frame class.  Construct a Frame object called  myFrame with a title "My first frame". 
   The frame class inherits the method   setSize(int width, int height) from the Component class which can be used to change the size of the Frame.  Use this method to change the size of  myFrame to a width of 100 and a height of 200.
   The Frame class inherits the method  setVisible(boolean b) from the Component class which allows us to make the Frame visible or not depending on whether we set  b to true or false.  Use this method to make  myFrame visible.
   Look up the method  setLocation and use this method to move the Frame on the screen to position (10,20).
2. Look up the Color class.  Construct a Color object called  myColor with a red value of 10, a green value of 100, and a blue value of 50.  How would you make a brighter or darker version of this color?
3. Look up the Button class.  Construct a Button object called  myButton with a label "Push me".  How would you change the label on myButton to "Push me, again" ?
4. Look up the Graphics class.  Construct a Graphics object called g.  How would you draw a line that starts at point (10,20) and ends at point (50,60) in the graphics object?