PROJECT: ClassRepo

Overview

ClassRepO is a desktop address book application written in Java that targets secondary schools for usage by their students, tutors and administrative staff. This portfolio is meant to document the contributions that I made to the project.

Roles

In this project, I serve mainly as a Code Quality checker. Aside from the code quality, I also ensure that the language used in the documentation is up to standard.

Summary of contributions

  • Code Contributions: here

  • Major enhancement: added a new field Attendance which comes with a few commands

    • What it does: Enables the ClassRepO to keep track of the students' attendance.

    • Justification: This feature improves the product significantly as a school already needs to take the students' attendance. A digitalized storage and management of the attendance will make data analysis faster and also reduces the usage of paper (eco-friendly).

    • Highlights: This feature uses different forms of software tricks (storage type) to make searching and editing of data more efficient.

    • Credits: Victor Hernandez for the base valid date checker method

  • Other contributions:

    • Project management:

      • Added config.json file to fix repoSense issue: #210

    • Enhancements to existing features:

      • Continuously updated the feature introduced by me (attendance): #214 | #209 | #126 | #68

      • Wrote additional tests for existing features to increase coverage: #214 | #209 | #126 | #68

    • Documentation:

      • Reviewed grammar and spelling for UG and DG: #270| #209

    • Community:

      • PRs reviewed (with non-trivial review comments): #221

Contributions to the User Guide

Given below are sections I contributed to the User Guide. They showcase my ability to write documentation targeting end-users.

Attendance Section

Attendance Commands

Below are the commands that deal with attendance data:

Updates the attendance of a person: attendance 16

Updates the attendance of the target person.
Format: attendance INDEX d/DATE att/ATTENDANCE

Updates the attendance of the person with INDEX as specified by the last shown list.
*If the input date is 0 (e.g. d/0), the current date will be used

Example(s):

  • list
    attendance 1 d/29-09-2018 att/1
    Marks the attendance of the first person in the list as present for the date 29th September 2018.

  • list
    attendance 1 d/0 att/0
    Marks the attendance of the first person on the list as absent for today’s date.

Replaces the attendance of a person: replaceAtten 16

Replaces the current attendance of the target person.
Format: replaceAtten INDEX d/DATE att/ATTENDANCE

Replaces the attendance of the person with INDEX as specified by the last shown list.

Example(s):

  • list
    replaceAtten 1 d/29-09-2018 att/1
    Replaces the attendance of the first person in the list as present for the date 29th September 2018.

View the attendance of a person: viewAttenPerson 16

View the attendance of the target person.
Format: viewAttenPerson INDEX

View the attendance of the person with INDEX as specified by the last shown list.

Example(s):

  • list
    viewAttenPerson 1
    Views the attendance of the first person on the list.

View the attendance of a date: viewAttenDate 16

View the attendance of the given date.
Format: viewAttenDate DATE

Shows a list of people who were present and absent on a particular date.
If a person’s attendance has yet to be taken, the person’s name will default be under absent.
*If the input date is 0 (e.g. d/0), the current date will be used

Example(s):

  • viewAttenDate d/28-10-2018
    Shows a list of people who were present on a particular date.

  • viewAttenDate d/0
    Shows a list of people who were present today.

Replaces the attendance of a person: replaceAtten 16

Replaces the current attendance of the target person.
Format: replaceAtten INDEX d/DATE att/ATTENDANCE

Replaces the attendance of the person with INDEX as specified by the last shown list according to the DATE.

Example(s):

  • list
    replaceAtten 1 d/29-09-2018 att/1
    Replaces the attendance of the first person in the list as present for the date 29th September 2018.

Coming in v2.0:

Update multiple people attendance: multiAtten 16

Updates the attendance of multiple people based on the list of index.
Format: multiAtten i/MULTIPLE_INDEX d/DATE att/ATTENDANCE

Updates the attendance of muultiple people with a list of INDEX as specified by the last shown list.
*If the input date is 0 (e.g. d/0), the current date will be used
*If the input index is 0 (e.g. i/0), all people in the addressbook will be updated

Example(s):

  • list
    multiAtten i/1 2 4 5 d/29-09-2018 att/1
    Marks the attendance of the people with index 1, 2, 4 and 5 in the list as present for the date 29th September 2018.

  • list
    attendance i/0 d/0 att/0
    Marks the attendance of everybody on the list as absent for today’s date.

Contributions to the Developer Guide

Given below are sections I contributed to the Developer Guide. They showcase my ability to write technical documentation and the technical depth of my contributions to the project.

Implementation of Attendance

Attendance Feature

ClassDiagram Attendance
Figure 1. Class Diagram of the Attendance feature
ClassDiagram Attendance with Methods
Figure 2. Class Diagram that links from UniquePersonList to Attendance object, including methods

The attendance field is an additional field to every Person object:

  1. Each Person will have an Attendance object

  2. Each Attendance object will contain a Hashmap, which will store the attendance of each person by keying each String date to a boolean isPresent.

  3. UniquePersonList will contain 2 lists, containing a list of people who are present or absent for each particular date.

  4. Users can thus check the attendance of a particular person, or for a particular date.

Current Implementation

The AddressBook contains the attendance of each person for each date that his/her attendance is taken. The current set of commands include:

  1. Updating a person’s attendance

  2. Replacing a person’s attendance

  3. Viewing of a person’s attendance

  4. Viewing of present people on a particular date

An example of how feature 1 - Updating a person’s attendance works:

  1. The user (teacher/ admin) will be able to use the 'attendance' command to update the attendance of a particular person (student).

  2. The specific person is extracted from the AddressBook.

  3. A check is performed to check if the person already has his/her attendance taken.

  4. If the attendance has already been taken, the user will be prompted to use another command replaceAtten to replace the attendance.

  5. If the attendance has yet to be taken, the attendance of the specified person for the specified date will be taken as either 'present' or 'absent'.

Design Considerations

Aspect: How to store attendance for each person

  • Alternative 1 (Current choice): Each person has a hashmap that stores the date to the attendance.

    • Pros: Hashmaps allows more efficient checking of duplicate attendance (get() method has a complexity of O(1).

    • Cons: Values and Keys in hashmap are not sorted.

  • Alternative 2: Each person has a list of strings containing the date and attendance.

    • Pros: A list of strings will allow easier storage and viewing of the data

    • Cons: List or ArrayList will require O(n) time to check for duplicates

    • Cons: A single string will not allow handling of data separately

  • Alternative 3: Each person has a list of pairs containing date and attendance.

    • Pros: Pairing of date to attendance ensures that the checking of attendance requires at most O(n) time, but minimally O(1)

    • Cons: Usage of pairs in java will require an extra class or an external library, which is unnecessary

Aspect: How to check if attendance has duplicate

  • Alternative 1 (Current choice): Use a boolean to check if there is a duplicate date in the hashmap.

    • Pros: Booleans only have 2 value, and thus there is no need to define a string with a proper variable name

    • Cons: Booleans are fixed as true and false, thus needed additional code to translate the result into a string so that the user can understand the results easily.

  • Alternative 2: Use a separate class, 'hasDuplicate' to check for duplicate date

    • Pros: An additional class means that the code will be more encapsulated, fulfilling the purpose of OOP.

    • Cons: Additional code will be required to create the additional class

Aspect: How to differentiate between updating and replacing a person’s attendance

  • Alternative 1 (Current choice): Using an additional parameter (Boolean overWrite) that is fixed in the command.

    • Pros: No confusion for the user since the parameter to overwrite is fixed.

    • Pros: THere is no need to have 2 separate methods in the Attendance object as both updating and replacing of attendance has very similar functions.

    • Cons: There is a need to check for an additional parameter in the same method, which may lengthen the code and cause minor 'arrowhead' coding.

  • Alternative 2: Treat the 2 commands as 2 completely separate commands and execute them individually.

    • Pros: The 2 commands will each be short, simple and easy to understand.

    • Cons: There will be 2 methods with extremely similar functions, which is redundant.

  • Alternative 3: Have the user input an additional parameter (Boolean overWrite) if they want to overwrite the current data

    • Pros: Similar to alternative 1, having the user input an additional parameter and only having 1 method in the Attendance object can reduce the need to have unnecessary duplicates in the code.

    • Cons: An additional parameter will require a change in the parser.

Aspect: How to store data in XML, addressbook.txt

  • Alternative 1 (Current choice): Use 2 list to store a list of dates and a list of absent/present

    • Pros: Simple implementation, and utilizes the fact that each date can only have either present/absent. Iterating through the map to generate the 2 lists will thus ensure that the data is in order

    • Cons: In the XML format, data will be stored as 2 separate lists, which may not be as user-friendly to edit directly.

  • Alternative 2: Use a list of pairs, Pair <String Date, Boolean isPresent>

    • Pros: Only requires 1 single list to store the data of the entire map.

    • Cons: Such implementation will require a Pair object, which will require additional methods and classes, thus requiring longer code.

  • Alternative 3: Convert Hashmap to XML directly

    • Pros: Direct transfer of data will thus require less memory space to store the same data.

    • Cons: A Hashmap to XML converter will require either a very long code (unnecessary for only 1 map), or requires the import of an external library.

Coming in v2.0

Aspect: : How to implement multiAtten Command

  • Alternative 1 (Most likely choice): multiAtten command calls the attendance command multiple times

    • Pros: Reduce the need for repeated code since the multiAtten command is very similar to attendance command.

    • Pros: Simpler to implement when the input is 0 as there is no need to catch index 0 since index 0 will not exist in the UniquePersonList.

    • Cons: Increase in coupling as a change in attendance command will cause multiAtten command to change.

  • Alternative 2 (Unlikely choice): Reimplement the command as a brand new command

    • Pros: Cleaner codes

    • Pros: A brand new implementation would allow for future upgrades

    • Cons: Lengthier and repeated code