1. CSC 222: Object-Oriented Programming
Fall 2015
Object-oriented design
OO design review
objects, cohesion, loose coupling, polymorphism, …
Model-View-Controller (MVC) pattern
netBeans IDE
create/edit/run a project, advanced features
GUIBuilder, Swing GUI toolkit

2. Object-oriented development
OO design is the dominant approach to large-scale software development
developing cohesive (& loosely coupled) software objects allows for
independent teams to contribute
independent testing & debugging
easier code reuse
polymorphism via interfaces allows for
independent development (interface serves as contract)
generic code that can work on entire hierarchies of classes
polymorphism via inheritance allows for
code reuse (can extend existing code without direct access)

3. BlueJ  netBeans
BlueJ is an Interactive Development Environment (IDE) designed for novice programmers
simple to use
visual interface makes class vs. object distinction clear
can directly manipulate objects & call methods using mouse clicks
can also write and execute statements in the Code Pad
however, it is somewhat limiting to experienced programmers
netBeans is a popular, industry-strength IDE for developing software
free & open-source
multi-platform (Mac, Windows, Linux)
multi-language (Java, PHP, C/C++, …)
has an integrated GUI builder
download from netbeans.org

4. Create a project

5. Select location & project name

6. Adding a file to the project

7. Select location & file/class name

8. Can then edit the default file

9. Completing a project each class in the project is its own file
one class must have a public static void main method
when you run the project, this main method is executed

10. Editor features
code completion when type OBJECT., see list of method options
Source menu
Format will try to indent selected lines consistently
Shift Left / Shift Right will manually indent selected lines
Toggle Comment comments/uncomments selected lines
Refactor
Rename can change a class/variable/method name
throughout the project
Run
Build Main Project compile all classes in the project
Run Main Project execute the main method
note: can also right-click on a file and select Run File

11. example: Magic 8-ball create a new project named Magic
use the default option to create a default main class named TerminalUI
download the Die.java class into the src folder of this project
define a new class named Magic8Ball
has a 3-sided Die object as a field
has a getAnswer method that takes a String as input (a question) and returns one of 3 possible answers at random: "Definitely", "No way", or "Outlook hazy"
define a new class named TerminalUI, in the main method
prompt the user for a question
call getAnswer and display the answer

12. MVC pattern
model-view-controller is a software pattern used to develop reusable, modular software
goal: isolate the application-specific logic from the user interface
allows for independent testing & development, easy updates
for this example:
the model consists of the logic of the application – Die & Magic8Ball
the view is the Java terminal window
the controller is the TerminalUI class with its text-based input/output
by separating the logic from the interface, it makes it possible to plug in a different interface, e.g., a Graphical User Interface (GUI)

13. GUIBuilder netBeans has an integrated GUI builder built-in
can create a (Swing) GUI using a drag-and-drop interface

14. Naming the GUI class

15. GUI design view

16. Build interface
drag GUI elements from the Palette onto the Design Frame
can arrange, resize, alter Properties of the elements
in particular, right click and change names of elements to be meaningful
(e.g., questionArea, answerButton, answerBox)

17. Associate events with elements
right click on element, select the event you want to handle

18. Source view
click on the Source button to see the generated code

19. Completing the GUI add the Controller code to the GUI class
here, Magic8Ball object is a field, initialized in constructor
code for I/O & method call are entered into the event-handler method

20. Wumpus GUI we could similarly define a GUI for Hunt the Wumpus
Model: CaveContents + Cave + CaveMaze (note: no I/O in these classes)
View: window with text area (for output) and buttons (for input)
Controller: JFrame that connects GUI elements with CaveMaze model