Shannon Wong - Project Portfolio

PROJECT: Part-Time Manager (PTMan)

Overview

PTMan is a desktop human resource application used for managing part-time employees.

PTMan aims to give part-time employees the freedom of choosing when they want to work by registering for the available shifts set by the manager. Thereby reducing the hassle of work scheduling for both employers and employees.

The user interacts with the application using a CLI, and it has a GUI created with JavaFX. It is written in Java, and has about 10 kLoC.

Summary of contributions

Major enhancement: Added the shift feature.
- What it does: Allows employers to create work shifts. Employees can then apply for the shifts that they want to work in.
- Justification: This feature allows for easy management of manpower while giving employees the freedom and flexibility to work whenever they want to.
- Highlights: This enhancement modifies the app’s model to store shifts. The storage component also had to be modified to save shifts to local storage. There were design considerations to integrate shifts into the existing model while minimizing coupling with the other components. To enable user interaction with this feature, various commands that manipulate shifts had to be implemented.
Minor enhancement: Added command aliases that are shorthands for the full commands.
Code contributed: [Functional code] [Test code]
Other contributions:
- Project management:
  - Managed milestones and issue-tracking on GitHub.
- Documentation:
  - Added cross-reference links to the User Guide and Developer Guide: [#154] [#159]
  - Ensured that the language and format of the documentation are correct and consistent: [#154]
- Tools:
  - Integrated TravisCI to the team repo.
  - Integrated Coveralls to the team repo.
  - Integrated Codacy to the team repo.

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.

Adding a shift: `addshift`

Adds a shift to the timetable to indicate that you require employees at that period.

Format: addshift d/DATE ts/START_TIME te/END_TIME c/EMPLOYEE_CAPACITY
Shorthand: as d/DATE ts/START_TIME te/END_TIME c/EMPLOYEE_CAPACITY

The DATE should be in DD-MM-YY format.
The START_TIME and END_TIME are in HHMM format.
The CAPACITY should be a positive integer.

Guided Example:

To add a shift on 13th April 2018 from 12pm to 6pm that requires 3 employees, execute the command
addshift d/13-04-18 ts/1200 te/1800 c/3 as shown in Figure 1.

Figure 1. PTMan Add Shift Command
You should see a confirmation message in the result display along with the shift you’ve added being displayed in the timetable. This is illustrated in Figure 2.

Figure 2. Successful Adding of a Shift in PTMan

Deleting a shift: `deleteshift`

Deletes a shift from the timetable.

Format: deleteshift SHIFT_INDEX
Shorthand: ds SHIFT_INDEX

The SHIFT_INDEX refers to the shift number in the timetable.
The SHIFT_INDEX must be a positive integer 1, 2, 3, …

Guided Example:

If you wish to delete shift 1, execute the command deleteshift 1 as shown in Figure 3 below.

Figure 3. PTMan Delete Shift 1 Command
Upon successful deletion, you will see a confirmation message in the result display and you can no longer see the shift in the timetable. Figure 4 illustrates the successful deletion of shift 1.

Figure 4. Successful Deletion of Shift 1 in PTMan

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.

Shifts Feature

Reason for implementation

PTMan is designed to give employees the freedom and flexibility to choose the shifts they want to work in. By allowing employers to add or delete shifts, employees can then apply for the shifts that are available.

How it is implemented

The Shift class represents a shift in PTMan.

It stores:

The Date of the shift. Date is a class that wraps Java’s LocalDate class.
The starting and ending Time of the shift. Time is a class that wraps Java’s LocalTime class.
The employee Capacity for the shift. Capacity is a class that wraps an integer.
The UniqueEmployeeList of employees working in the shift. UniqueEmployeeList is a list that stores the Employee objects of employees that have applied for the shift. It guarantees there are no duplicate employees in the shift.

Figure 5 is a class diagram that displays the association between Shift and other components in the Model.

Figure 5. Overview of the Shift Class in the Model Component

Date and Time use Java’s LocalDate and LocalTime classes for easy integration with the timetable. They also make formatting and parsing simple through the use of Java’s DateTimeFormatter.

To store a list of shifts in PartTimeManager, we use a UniqueShiftList to ensure there are no duplicate shifts.

Commands

The following are commands that directly interact with the Shift class:

AddShiftCommand: Creates a Shift and adds it to the UniqueShiftList in PartTimeManager.
DeleteShiftCommand: Deletes a Shift from the UniqueShiftList in PartTimeManager.
ApplyCommand: Adds an Employee to the UniqueEmployeeList in the Shift.
To adhere to defensive programming practices, instead of simply adding the Employee to the Shift, ApplyCommand does the following:
1. Create a copy of the specified Shift
2. Add the Employee to the copy.
3. Replace the original Shift with the copy.
UnapplyCommand: Removes an Employee from the UniqueEmployeeList in the Shift.
Similar to ApplyCommand, UnapplyCommand will:
1. Create a copy of the specified Shift.
2. Remove the Employee from the copy.
3. Replace the original with the copy.

Shift indexing

The commands DeleteShiftCommand, ApplyCommand and UnapplyCommand access the specified Shift via it’s index displayed on the timetable. The preferred behaviour for the indexes is to have the first shift of the week start from index 1, with subsequent shifts incrementing that index. However, having shifts that are earlier than the current timetable week will cause the first shift of the week to have an index that is greater than 1.
As seen in Figure 6 below, the shift on Monday has index 5 because there are 4 other shifts in the week(s) before the current week.

Figure 6. Example of Undesired Shift Indexing

To avoid this, we only want to index shifts that are visible in the current timetable view.
This can be achieved by setting the Predicate<Shift> for the FilteredList<Shift> in ModelManager to filter shifts in the current week as shown below:

// In Model
public static Predicate<Shift> PREDICATE_SHOW_WEEK_SHIFTS = shift ->
    getWeekFromDate(shift.getDate().getLocalDate()) == getWeekFromDate(LocalDate.now());

// In ModelManager
updateFilteredShiftList(PREDICATE_SHOW_WEEK_SHIFTS);

This results in the desired shift indexing as shown in Figure 7 below.

Figure 7. Example of Desired Shift Indexing