Homework Assignment 8

Adding a GUI Front End to AssociationLists

810:062
Computer Science II
Object-Oriented Programming

Due: Friday, April 8, at 4:00 PM

Introduction

Back in Homeworks 3 and 4, you wrote AssociationList, which defines a class of a simple key/value databases. We can add entries to an AssociationList, remove and update entries, and retrieves by key and full-text search. We can also clear the list, read associations from a file, and save them to a file.

Now that we have begun to learn how to implement graphical interfaces in Java, we can take the next natural step and design a graphical note-taking program. We will call our program a Notebook.

Programming Advice

Use your solution to Homework 4 as the code for your AssociationList. Use the ideas you've studied in Sessions 15 through 22 to implement your GUI interface.

As always, write your program in the style we have been using all semester. Take small steps. We can't write tests very easily for graphical programs, but we can choose to implement our program in small steps. Before you write a new bit of code, you should know just what you would like that code to do, and how you will be able to tell if your code does it. Only then should you write the code. Refactor your code after each step, to ensure that your program is as easy to extend with the next functionality as possible.

Tasks

Write the following three files:

1. Notebook.java

   Notebook consists only of a main() method. This method creates an AssociationList, creates a NotebookFrame, and displays the frame on the screen.

   Notebook takes one optional command-line argument, the name of a file of Associations. If the user does not give a command-line argument, then the AssociationList starts empty. If the user does give a command-line argument, then the corresponding file of associations is loaded into the AssociationList.

   (Remember: AssociationLists know how to load Associations from a file!)

2. NotebookFrame.java

   A NotebookFrame is a window with at least these components:

   • a TextField for entering and displaying keys
   • a set of Buttons for sending messages to the AssociationList
   • a TextArea for entering and displaying values
   • a region for displaying miscellaneous messages to the user

   You should have buttons for sending the following messages to the AssociationList:

   • add a new key/value pair
   • lookup all associations having the key in the key field, displaying all corresponding values in the value area
   • findAll all associations that contain the string in the key field, displaying all corresponding values in the value area
   • remove the association specified by the strings in the key field and value area
   • update all associations having the key in the key field, by appending the string in the value area to their values
   • clear the AssociationList
   • save all associations ToFile, using the string in the key field as the name of the output file
   • load associations FromFile, using the string in the key field as the name of the input file (adds loaded associations to the existing set)
   • load associations into an empty AssociationList FromFile whose name is specified in the key field, in Sorted order

   Some further instructions:

   • Notice that the AssociationList class provides all of the database services that your Notebook needs. You should not have to change or even peek inside the AssociationList.

   • Use the 'miscellaneous messages' area to display status information to your user. For example, you should display messages such as "file not found", "file loaded successfully", and "no matching notes found".

   • You might want to use separate panels for the different areas in your frame, and GridLayouts for the button panel and the NotebookFrame itself.

   • You should, of course, make separate Java files for all non-trivial classes.

   You may lay out your frame it in whatever way you wish. Feel free to add graphical flourishes to your interface -- so long as you have the required functionality done first!

3. readme.txt

   This text file explains the design of your program and lists all of its Java files, in the order they appear in your print-out

Deliverables

By the due date and time, submit the files

• readme.txt
• Notebook.java
• NotebookFrame.java
• any other *.java files you create, in an order that makes sense to the reader

Be sure that your submission follows all homework submission requirements.