The very first BlueJ lab. Draw the house of your dreams.
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Project "picture"
Authors: Michael Kölling and David J. Barnes

This project is part of the material for the book

Objects First with Java - A Practical Introduction using BlueJ
David J. Barnes and Michael Kolling
Pearson Education, 2002

It is discussed in chapter 1.

This is a very simple project to demonstrate some characteristics of

You can create various shapes, and you will see, if you do, that those
shapes are drawn on screen (in a window that we call the "canvas").

You can then manipulate these objects: change their position, size and
colour. Try it out: create a few different squares, triangles and circles.

This project is designed as a first example of object-oriented programming.
It illustrates a number of concepts:

- a Java project (application) is a collection of classes
- objects can be created from classes
- from any one class, many objects may be created
- objects have operations (methods)
- operations can have parameters
- parameters have types (at least String and int)
- objects hold data (fields)
- the operations and fields are common to all objects
- the values stored in the fields can be different for each object

The project also demonstrates

- BlueJ object creation
- interactive method invocation
- parameter passing

A good second project to look at after this is "picture", which adds a class
to those ones in this project. That class (named "Picture") uses the shapes
to draw a picture. It can be used to experiment with coding.

Michael Kölling, July 2000