Exercise 06: Club Membership

Reform Club, Wikimedia Commons

This week’s lab work is intended give you more practice using collections.

Prelab

What to Bring to Lab

Please prepare these exercise before coming to the lab.

P1. How do you write the import statement for using an ArrayList?

P2. How do you define a field that will take a collection of objects of type Student? How does it get initialized?

P3. Write a method that returns true if the parameter month is valid, i.e. between 1 and 12.

P4. How can you compare two names, stored as Strings, to see if they are the same?

Post-Lab, AKA What To Turn In

Your completed assignment, should be submitted to Moodle in two files: The lab report as a pdf, and the sources as zip. The lab report should include:

• The names of all people in your group and mentions of any other collaborators in any parts of the exercise, if applicable.
• A description of what you did during the lab, including a record of what worked, what problems you encountered, and answers to the questions as asked.
• A screenshot or two demonstrating that your code works.
• A record of how long you needed for this lab and what you learned.

Lab assignments are due before your next lab at 23.00. They may, of course, be turned in earlier.

As always, you may work on the assignment in groups; but each of you has to upload the (same!) report & source files from his or her own account!

Assignment

Club Membership

1. Use the club project at https://github.com/htw-imi-info1/exercise06-archived-club-membership/ to complete the following exercises. There is an outline in the project, but it doesn’t do anything useful. The club class is intended to store Membership objects in a collection. Define a field for an ArrayList for keeping track of club members. Make sure this compiles before moving on.
2. Complete the numberOfMembers method to return the current size of the collection. Since you can’t add anyone yet, this will, of course, at the moment always return 0.
3. A complete version of Membership is supplied for you. It stores members names and the month and year that they joined the club. Complete the join method. Add some members and see if the numberOfMembers still works. What do you have to do in order to test this?
4. Implement a method numberJoinedInMonth that takes a month number and a year number as parameters and returns the number of persons who joined in that particular month of that year.
5. Implement a method listJoinedInMonth that takes a month number and a year number as parameters and prints out the names of those who joined in this month. The bored can sort the list by name.
6. Implement a method search that looks for members with a particular name. It should return the Membership object if a member with that name was found, null otherwise.
7. Implement a method remove that removes the member with a particular name, using an iterator.
8. Adapt the join method so that no two people with the same name can join the club. We don’t care about capitalization, so “John” is the same as “john”. Output an appropriate error message containing “Duplicate name”.
9. (For the bored) Define a method to remove all members in the club’s collection who joined in a particular month and year, returning the ones removed in a separate collection object.
10. (For the bored) Define a method to list all members of the club sorted first by year joined, then by month joined, and finally by name.
11. (For the really bored) Extend the Membership object to include further information such as birthday. Make search methods for finding all the members who have a birthday in a particular month, and finding people who will be having “round” birthdays in the current year. There can be three meanings of “round”, regular, prime and computing. Regular is 20, 30, 40, 50, 60, 65, 70, 75, 80, 85, 90, 95, 100. Prime is prime number ages. Computing is 16, 25, 26, 32, 36, 42, 49, 64, 81. Explain the computing numbers.