©2010 Felleisen, Proulx, et. al.
In this lab we will focus on understanding data definitions, the distinction between information and data, how information can be represented as data, how to interpret the information that some instance of data represents, and learn to encode the data definitions, as well as construct instances of data in a class based language (like Java).
We will work in a professional Integrated Development Environment (IDE) Eclipse using the language FunJava.
In the first part of this lab you will learn how to work in a commercial level integrated development environment IDE Eclipse, using the standard Java programming language. The environment provides an editor, allows you to organize your work into several files that together comprise a project, and has a compiler so you can run your programs. Several projects form a workspace. You can probably keep all the work till the end of the semester in one workspace, with one project for each programming problem or a lab problem.
There are several step in getting started:
Learn to set up your workspace and launch an Eclipse project.
Learn to manage your files and save your work.
Learn how to edit FunJava programs and run them, using the tester library.
Start working on two adjacent computers, so that you can use one for
looking at the documentation and the other one to do the work. Find
the web page on the documentation computer:
http://www.ccs.neu.edu/howto/howto-windows-n-unix-homedirs.html
and follow the instructions to log into your Windows/Unix account on
the work computer.
Next, set up a workspace folder in your home directory where you will
keep all your Java files. This should be in
z:\\...\EclipseWorkspace
Note that z: is the drive that Windows binds your UNIX home directory.
Next, set up another folder in your home directory where you will
keep all your Java library files. This should be in
z:\\...\EclipseJars
We will refer to these two folders as EclipseWorkspace and EclipseJars. Make sure the two folders EclipseWorkspace and EclipseJars are in the same folder.
Start the Eclipse application.
DO NOT check the box that
asks if you want to make this the default workspace for Eclipse
if you are working on the lab computer. If you are working at home or
using your laptop, you may want to make the selected workspace to be
your default.
Working at home: If your home computer does not have Java compiler installed, please, consult the wiki, or ask one of the TAs or tutors to help you.
Download the libraries we will use. The libraries you will need are available at a public web site at:
http://www.ccs.neu.edu/javalib/
Go to the Downloads folder and download the following libraries into your EclipseJars folder:
tester.jar
draw.jar
geometry.jar
colors.jar
When saving the downloaded file, the dialog asks you Do you want to open or save this file. Choose save. It then comes up with a Save as window. Browse to find your EclipseJars folder and on the bottom where it says Save as type instead of WINRAR archive choose All Files. Do this for all Java libraries, otherwise Windows messes up the file.
You will also need the library funjava.jar that handles the FunJava language. The link is
http://www.ccs.neu.edu/home/vkp/2510-sp10/Labs/Lab2/funjava.jar
Create a project.
In the File menu select New then Java Project. In the window that appears in the Project layout section select Create separate folders for sources and class files and select Next. We assume you have named it MyProject.
In the Java Settings pane select the Libraries tab.
On the right click on Add External JARs...
You will get a chooser window. Navigate to your EclipseJars folder and select all jar files you have downloaded.
Hit Finish.
Add the Shapes.java file to your project.
Download the file Shapes.java to a temporary directory or the desktop.
In Eclipse highlight the src box under the MyProject in the Package Explorer pane.
Note: If the pane is not visible, go to Window menu, select Show View... then Package Explorer. You should also select Show View... Outline.
In the File menu select Import....
Choose the General tab, within that File System and click on Next.
Browse to the temporary directory that contains your Shapes.java file.
Click on the directory on the left, then select the Shapes.java file in the right pane and hit Finish.
View and edit a FunJava file Shapes.java.
Click on the src block under MyProject in the Pacakage Explorer pane. It will reveal default package block.
Click on the default package block. It will reveal Shapes.java.
Double click on Shapes.java. The file should open in the main pane of Eclipse. You can now edit it in the usual way. Notice that the Outline pane lists all classes defined in this file as well as all fields and methods. It is almost as if someone was building our templates for us.
The TAs will guide you through setting that will convert all tabs into spaces, and will show you how to set the editor to show you the line numbers for all lines in the code.
Add one new example of data for each class: Circle, Rect, and Combo.
Set up the run configuration and run the program.
Highlight MyProject in the Package Explorer pane.
In the Run menu select Run Configurations....
In the top left corner of the inner pane click on the leftmost item. When you mouse over it should show New launch configuration.
Select the name for this configuration - usually the same as the name of your project.
In the Main class: click on Search....
Among Matching items select FunJava (default package) and hit OK.
Click on the tab (x)= Arguments. In the Program arguments text field enter "src\Shapes.java" (if you are running Mac/OS or Linux, use "src/Shapes.java").
Later, when you define your own program, you will use your file name instead of Shapes.java. Make sure your file name does not have spaces in it.
At the bottom of the Run Configurations select Apply then Run.
Next time you want to run the same project, make sure Shapes.java is shown in the main pane, then hit the green circle with the white triangle on the top left side of the main menu.
Look at the following data definitions in the Beginner Student HtDP language:
;; Sample data definitions -- simple classes of data ;; to represent a pet ;; A Pet is (make-pet String Num String) (define-struct pet (name weight owner)) ;; Examples of pets: (define kitty (make-pet "Kitty" 15 "Pete")) (define spot (make-pet "Spot" 20 "Jane"))
Draw the class diagram for this data definition.
Create a new project in Eclipse, create a file Pet.java and convert the data definition to the FunJava language — including the examples of data.
Create a new Configuration and run the examples.
If you are comfortable with this material, you may omit the next two questions.
Convert the following class diagram into FunJava language:
+--------------+ | Restaurant | +--------------+ | String name | | String kind | | int avgPrice | +--------------+
Convert the following information to data examples for your Restaurant class.
Chinese restaurant Blue Moon with average price per dinner $15
Japanese restaurant Kaimo with average price per dinner $20
Mexican restaurant Cordita with average price per dinner $12
Look at the following data definitions in the Beginner Student HtDP language:
;; to represent a pet ;; A Pet2 is (make-pet String Num Person) (define-struct pet2 (name weight owner)) ;; to represent a person - a pet's owner ;; A Person is (make-person String Num Boolean) (define-struct person (name age male?)) ;; Examples of person data: (define pete (make-person "Pete" 15 true)) (define jane (make-person "Jane" 19 false)) ;; Examples of pet2 data: (define kitty2 (make-pet "Kitty" 15 pete)) (define spot2 (make-pet "Spot" 20 jane))
Draw the class diagram for this data definition.
Convert the data definition to the FunJava language — including the examples of data.
If you are comfortable with this material, you may omit the next two questions.
Convert the following class diagram into FunJava language:
+--------------+
| Restaurant2 |
+--------------+
| String name |
| String kind |
| int avgPrice |
| CartPt loc |--+
+--------------+ |
v
+--------+
| CartPt |
+--------+
| int x |
| int y |
+--------+
Make new examples for your Restaurant2 class.