Assignment 2

Be sure to type up your answers so you can submit them electronically on the BlackBoard Connect system. You may complete this assignment individually. Make sure all your files have your full name and student number on it.

Type up your answers using Eclipse. The file format of the Java program you are to submit must be .java.

This assignment is marked out of 33 points.

Due Date

February 15, 2014, 11:59AM (just before noon).

24 Hour Silence Policy

Due to the large class size and the potential volume of questions, we are implementing a 24-hour silence policy. This means that any questions posted on the discussion forum in the 24 hours immediately preceding the assignment deadline may not get answered in time. This does not mean that we will stop answering questions the moment the day before the deadline arrives, it just means that we cannot promise all the questions will be answered in time, due to our prior engagements, such as other classes and meetings we have.

For this reason, please be sure to attempt the assignment early, and try to complete it as if it were due two days prior to the real deadline.

In any case, we will try to answer all the questions that show up on the discussion forum. Note that questions sent to emails will not be answered, as we want all course related material to be viewed for everyone's benefit.

What You Are Given

There are 2 questions in this assignment. The first question is to practice polymorphism, and the second is on files.

Question 1 [20 points]

You are going to write a program that calculates the price of clothing with the appropriate provincial tax. The store will manage clothing from British Columbia, which has a PST of 7%, and Manitoba, which as a PST of 8%. Moreover, we will have two types of clothing: children and adult. Note that children clothing does not get taxed in any province.

In this question, complete the following:

4 points: Define an abstract class called Clothing that contains information about the clothing's brand and price (before tax). This class should have a constructor that initializes the attributes. This class should also have an abstract method called total() that returns the price of the clothing item after taxes have been applied.
3 points: Define a class called Children that inherits from Clothing. This class needs to have a constructor that initializes the brand and price. As well, this class will define the total() method. Finally, this class will define the toString() method to printing out all the attributes and final price after taxes of the item.
4 points: Define a class called Adult that inherits from Clothing. This class needs to have a constructor that initializes the brand and price. In addition, this class will define a constant GST at 0.05 to denote 5% of GST will be applied to the item. Then, the class will define the total() method which calculates the clothing price with GST (but not PST) on it. Finally, this class will define the toString() method to printing out all the attributes and final price after taxes of the item.
5 points: Define a class called BCAdult that inherits from Adult. This class needs to have a constructor that initializes the brand and price. In addition, this class will define a constant PST at 0.07 to denote 7% of PST will be applied to the item. Then, the class will define the total() method which calculates the clothing price with GST and PST on it. Note: You need to use the parent definition of total() for this part. Finally, this class will define the toString() method to printing out all the attributes and final price after both taxes of the item.
Define a class called MBAdult in the exact same way as you did for BCAdult. Follow the steps above. The only thing you should change is the class constant for MB tax, where the constant PST in this class is defined as 0.08 to denote 8% of PST.
4 points: Define a test class called Purchases that creates a polymorphic array of five Clothing references. Initialize the array with a variety of clothing objects, but be sure to include at least one of: Children, BCAdult, and MBAdult. Write a loop to print out the items by calling each array item's toString() method (implicitly or explicitly).

See sample output from the test class. Save your output into a file called Clothing-Output.txt.

Question 2 [13 points]

Write a simple HTML parser called TagParser that takes an input HTML file, extracts all the words between the an opening and closing pair of "tt" tags, and output those words (without the tags) into a plain text file.

An HTML file is a type of file used for websites. Unlike word, there is no function like boldface or italicize. To specify when a word should be displayed in a different way, tags are used. For example, to make a phrase bold, you would type "< b >a bold phrase< / b >" where "b" stands for bold and the angle brackets denote the tag. (There are no spaces inside the tags when you use them, they are just here for clarity.) In order for a computer to understand the difference between when it should start to bold and when it should stop, an opening tag and a closing tag are used. The closing tag just has an extra "/" in it. In this question, we will work with the HTML tag for "teletype text" (tt for short).

In this question, complete the following:

3 points: In the TagParser class, define a constructor that reads from a file. You should download the file at:
https://people.ok.ubc.ca/bowenhui/121/a2.html
and store it in your Eclipse project folder. Your program will read this file as input and extract information from it. In addition, your constructor will create a new file called a2-tagsOnly.txt which will store all the output later. Finally, your class will have a String array which will also be initialized in your constructor. You should initialize all your array elements to the following default string: "-1".
4 points: Add a method called parseTT() that detects when a line has an opening tt tag. Recall various String methods you can use here. When you have such a line, find the index position where the opening tag ends and the index position where the closing tag starts so you can extract the words in between. Once you extract the words in between, store that substring into your String array. When you are done, your array will have 33 extracted phrases.
4 points: Add a method called storeTT() that goes through each element in your String array via a loop and outputs it onto a separate line in the file you created earlier. Don't put any of the default values "-1" into the file. Be sure to close your file when you are done, otherwise it will seem like you have not written anything to the file.
2 points: Create a test class that gives the a2.html file to a TagParser object. Call the two methods you've created to test your program. Be sure to check your a2-tagsOnly.txt file to see if it has the information you expect.

Note: Be sure to handle your file I/O exceptions in one way or another. If you choose to let it propagate, you must still make sure that one of the caller methods handle it properly, without expecting someone else to handle it for you, and without letting it crash unexpectedly.

See sample file from the test class. There is no output from this class.

What to Submit

Be sure to comment all the methods and attributes for clarity. For this assignment, submit the following:

Clothing.java
Children.java
Adult.java
BCAdult.java
MBAdult.java
Purchases.java
Clothing-Output.txt
TagParser.java
TestParser.java (or test class file you used)
a2-tagsOnly.txt
Include your full name and student ID.
List the full names of the people who helped you in this assignment (include students and TAs if applicable), and mention what they helped you with -- failure to do so honestly will result in a lower mark and may be reported for academic discipline