TalentNexus Developer Guide

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Acknowledgements

This project is based on the AddressBook-Level3 (AB-3) project created by the SE-EDU initiative

As a result, both the User Guide and the Developer Guide were directly adapted from that of the original AAB-3 project:

• AB-3 User guide
• AB-3 Developer guide

Furthermore, the implementation of features listed below are adapted from and/or inspired by AddressBook-Level4 (AB-4):

• Undo and redo

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Setting up, getting started

Refer to the guide Setting up and getting started.

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Design

Architecture

The Architecture Diagram given above explains the high-level design of the App.

Given below is a quick overview of main components and how they interact with each other.

Main components of the architecture

Main (consisting of classes Main and MainApp) is in charge of the app launch and shut down.

• At app launch, it initializes the other components in the correct sequence, and connects them up with each other.
• At shut down, it shuts down the other components and invokes cleanup methods where necessary.

The bulk of the app's work is done by the following four components:

• UI: The UI of the App.
• Logic: The command executor.
• Model: Holds the data of the App in memory.
• Storage: Reads data from, and writes data to, the hard disk.

Commons represents a collection of classes used by multiple other components.

How the architecture components interact with each other

The Sequence Diagram below shows how the components interact with each other for the scenario where the user issues the command delete 1.

Each of the four main components (also shown in the diagram above),

• defines its API in an interface with the same name as the Component.
• implements its functionality using a concrete {Component Name}Manager class (which follows the corresponding API interface mentioned in the previous point.

For example, the Logic component defines its API in the Logic.java interface and implements its functionality using the LogicManager.java class which follows the Logic interface. Other components interact with a given component through its interface rather than the concrete class (reason: to prevent outside component's being coupled to the implementation of a component), as illustrated in the (partial) class diagram below.

The sections below give more details of each component.

UI component

The API of this component is specified in Ui.java

The UI consists of a MainWindow that is made up of parts e.g.CommandBox, ResultDisplay, RecruitListPanel, StatusBarFooter etc. All these, including the MainWindow, inherit from the abstract UiPart class which captures the commonalities between classes that represent parts of the visible GUI.

The UI component uses the JavaFx UI framework. The layout of these UI parts are defined in matching .fxml files that are in the src/main/resources/view folder. For example, the layout of the MainWindow is specified in MainWindow.fxml

The UI component,

• executes user commands using the Logic component.
• listens for changes to Model data so that the UI can be updated with the modified data.
• keeps a reference to the Logic component, because the UI relies on the Logic to execute commands.
• depends on some classes in the Model component, as it displays Recruit object residing in the Model.

Logic component

API : Logic.java

Here's a (partial) class diagram of the Logic component:

The sequence diagram below illustrates the interactions within the Logic component, taking execute("delete 1") API call as an example.

How the Logic component works:

1. When Logic is called upon to execute a command, it is passed to an AddressBookParser object which in turn creates a parser that matches the command (e.g., DeleteCommandParser) and uses it to parse the command.
2. This results in a Command object (more precisely, an object of one of its subclasses e.g., DeleteCommand) which is executed by the LogicManager.
3. The command can communicate with the Model when it is executed (e.g. to delete a recruit).
   Note that although this is shown as a single step in the diagram above (for simplicity), in the code it can take several interactions (between the command object and the Model) to achieve.
4. The result of the command execution is encapsulated as a CommandResult object which is returned back from Logic.

Here are the other classes in Logic (omitted from the class diagram above) that are used for parsing a user command:

How the parsing works:

• When called upon to parse a user command, the AddressBookParser class creates an XYZCommandParser (XYZ is a placeholder for the specific command name e.g., AddCommandParser) which uses the other classes shown above to parse the user command and create a XYZCommand object (e.g., AddCommand) which the AddressBookParser returns back as a Command object.
• All XYZCommandParser classes (e.g., AddCommandParser, DeleteCommandParser, ...) inherit from the Parser interface so that they can be treated similarly where possible e.g, during testing.

Model component

API : Model.java

The Model component,

• stores the address book data i.e., all Recruit objects (which are contained in a UniqueRecruitList object).
• stores the currently 'selected' Recruit objects (e.g., results of a search query) as a separate filtered list which is exposed to outsiders as an unmodifiable ObservableList<Recruit> that can be 'observed' e.g. the UI can be bound to this list so that the UI automatically updates when the data in the list change.
• stores a UserPref object that represents the user’s preferences. This is exposed to the outside as a ReadOnlyUserPref objects.
• does not depend on any of the other three components (as the Model represents data entities of the domain, they should make sense on their own without depending on other components)

Storage component

API : Storage.java

The Storage component,

• can save both address book data and user preference data in JSON format, and read them back into corresponding objects.
• inherits from both AddressBookStorage and UserPrefStorage, which means it can be treated as either one (if only the functionality of only one is needed).
• depends on some classes in the Model component (because the Storage component's job is to save/retrieve objects that belong to the Model)

Common classes

Classes used by multiple components are in the seedu.address.commons package.

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Implementation

This section describes some noteworthy details on how certain features are implemented.

Undo/redo feature

Implementation

The undo/redo mechanism is facilitated by VersionedAddressBook. It extends AddressBook with an undo/redo history, stored internally as an addressBookStateList and currentStatePointer. Additionally, it implements the following operations:

• VersionedAddressBook#commit() — Saves the current address book state in its history.
• VersionedAddressBook#undo() — Restores the previous address book state from its history.
• VersionedAddressBook#redo() — Restores a previously undone address book state from its history.

These operations are exposed in the Model interface as Model#commitAddressBook(), Model#undoAddressBook() and Model#redoAddressBook() respectively.

Given below is an example usage scenario and how the undo/redo mechanism behaves at each step.

Step 1. The user launches the application for the first time. The VersionedAddressBook will be initialized with the initial address book state, and the currentStatePointer pointing to that single address book state.

Step 2. The user executes delete 5 command to delete the 5th recruit in the address book. The delete command calls Model#commitAddressBook(), causing the modified state of the address book after the delete 5 command executes to be saved in the addressBookStateList, and the currentStatePointer is shifted to the newly inserted address book state.

Step 3. The user executes add n/David …​ to add a new recruit. The add command also calls Model#commitAddressBook(), causing another modified address book state to be saved into the addressBookStateList.

Step 4. The user now decides that adding the recruit was a mistake, and decides to undo that action by executing the undo command. The undo command will call Model#undoAddressBook(), which will shift the currentStatePointer once to the left, pointing it to the previous address book state, and restores the address book to that state.

The following sequence diagram shows how an undo operation goes through the Logic component:

Similarly, how an undo operation goes through the Model component is shown below:

The redo command does the opposite — it calls Model#redoAddressBook(), which shifts the currentStatePointer once to the right, pointing to the previously undone state, and restores the address book to that state.

Step 5. The user then decides to execute the command list. Commands that do not modify the address book, such as list, will usually not call Model#commitAddressBook(), Model#undoAddressBook() or Model#redoAddressBook(). Thus, the addressBookStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitAddressBook(). Since the currentStatePointer is not pointing at the end of the addressBookStateList, all address book states after the currentStatePointer will be purged. Reason: It no longer makes sense to redo the add n/David …​ command. This is the behavior that most modern desktop applications follow.

The following activity diagram summarizes what happens when a user executes a new command:

Design considerations:

Aspect: How undo & redo executes:

• Alternative 1 (current choice): Saves the entire address book.

  • Pros: Easy to implement.
  • Cons: May have performance issues in terms of memory usage.

• Alternative 2: Individual command knows how to undo/redo by itself.

  • Pros: Will use less memory (e.g. for delete, just save the recruit being deleted).
  • Cons: We must ensure that the implementation of each individual command are correct.

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Documentation, logging, testing, configuration, dev-ops

• Documentation guide
• Testing guide
• Logging guide
• Configuration guide
• DevOps guide

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Appendix: Requirements

Product scope

Target user profile:

• recruiters who manage a large number of applicants
• prefer desktop apps over other types
• prefers typing to mouse interactions
• is reasonably comfortable using CLI apps
• familiar with managing candidates across different countries

Value proposition: Provide a lightweight and flexible solution for recruiters to efficiently manage a network of global talents, optimised for both CLI and GUI usage.

User stories

Priorities: High (must have) - * * *, Medium (nice to have) - * *, Low (unlikely to have) - *

Use cases

For all use cases below, the System is TalentNexus and the Actor is the user, unless specified otherwise.

UC01 - Create a Recruit

MSS

1. User creates a recruit with the required parameters.

2. System shows success message and the details of the newly created recruit.

   Use case ends.

Extensions

• 1a. TalentNexus detects an invalid parameter.

  • 1a1. TalentNexus shows an error message informing which parameter is invalid.

  Use case ends.

• 1b. TalentNexus detects missing required parameter(s).

  • 1b1. TalentNexus shows an error message informing which parameter is required.

  Use case ends.
  

UC02 - View a Recruit

MSS

1. User views a recruit of a given UUID.
2. System shows the details of a the recruit with the given UUID.

Use case ends.

Extensions

• 1a. TalentNexus finds no recruit with the given UUID.

  • 1a1. TalentNexus shows an error message.

  Use case ends.

• 1b. TalentNexus detects that an invalid UUID is given.

  • 1b1. TalentNexus shows an error message.

  Use case ends.
  

UC03 - Search Recruit

MSS

1. User searches for recruits with the given parameters
2. System shows the list of recruits matching the criteria and their details.

Use case ends.

Extensions

• 1a. TalentNexus finds no recruit matching the search parameter.

  • 1a1. TalentNexus lists an empty list (i.e. 0 recruits are shown).

  Use case ends.

• 1b. TalentNexus detects that an invalid search parameter.

  • 1b1. TalentNexus shows an error message.

  Use case ends.
  

UC04 - Edit a Recruit

MSS

1. User edits a recruit of a given UUID by supplying the modified parameters.
2. System shows success message and the updated details of the modified recruit.

Use case ends.

Extensions

• 1a. TalentNexus finds no recruit with the given UUID.

  • 1a1. TalentNexus shows an error message.

  Use case ends.

• 1b. TalentNexus detects that the modification removes all contact parameters.

  • 1b1. TalentNexus shows an error message.

  Use case ends.

• 1c. TalentNexus detects illegal parameter combinations.

  • 1c1. TalentNexus shows an error message.

  Use case ends.
  

UC05 - Delete a Recruit

MSS

1. User deletes a recruit of a given UUID.
2. System shows success message and details of the deleted recruit.

Use case ends.

UC06 - Undo the Last Performed Operation

MSS

1. User undoes the last create, edit, or delete operations.
2. System shows success message and details of the recruit involved.

Use case ends.

Extensions

• 1a. TalentNexus finds no last performed operation.

  • 1a1. TalentNexus shows an error message.

  Use case ends.
  

UC07 - List All Available Commands

MSS

1. User requests for the list of available commands
2. System shows the list of all available commands and example usages.

Use case ends.

UC08 - Sort the Recruit List

MSS

1. User requests to sort the recruit list by one or more specified fields with sort order (ascending or descending).
2. System sorts the recruit list according to the specified fields and order, applying sort criteria in priority from left to right.
3. System displays the sorted list with a success message showing the field names and sort order.

Use case ends.

Extensions

• 1a. TalentNexus detects an invalid sort field.

  • 1a1. TalentNexus shows an error message informing that the sort field is invalid, and displays the correct format with valid fields.

  Use case ends.

• 1b. TalentNexus detects an invalid sort order.

  • 1b1. TalentNexus shows an error message informing that the sort order must be either "asc" or "desc".

  Use case ends.

• 1c. User does not specify any sort field.

  • 1c1. TalentNexus sorts by name in ascending order by default.
  • 1c2. System displays the sorted list with a success message.

  Use case resumes from step 3.
  

UC09 - Archive/Unarchive a Recruit

MSS

1. User requests to archive/unarchive a recruit by its UUID or its index in the list order.
2. System archives recruit and hides them from the main list (list)

Use case ends.

Extensions

• 1a. The Recruit with the provided UUID/Index is already archived

  • 1a1. TalentNexus shows an error message.

  Use case ends.

• 1b. TalentNexus detects that an invalid UUID/Index is given.

  • 1a1. TalentNexus shows an error message.

  Use case ends.
  

Non-Functional Requirements

1. Should work on any mainstream OS as long as it has Java 17 or above installed.
2. Should work regardless of the user's operating system languages and locale.
3. Should be able to hold up to 1000 recruits without a noticeable sluggishness in performance for typical usage.
4. A user with above average typing speed for regular English text (i.e. not code, not system admin commands) should be able to accomplish most of the tasks faster using commands than using the mouse.
5. Should be immediately usable without any installation process required.
6. Should work well on machines with screen resolutions of at least 1920 x 1080, and remain usable on lower screen resolutions.
7. Should not be more than 100MB of size.
8. Should search across 1000 recruits at under 1 second.

Glossary

• PDPA (Personal Data Protection Act): Regulations governing the handling of Personal data
• Recruit: A recruit being considered for a job role
• Mainstream OS: Windows, Linux, Unix, MacOS
• UUID: Universally Unique Identifier is a unique identifier generated by the java.util.UUID library which allows us to assign a unique identifying ID to each recruit.

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Appendix: Instructions for manual testing

Given below are instructions to test the app manually.

Launch and shutdown

1. Initial launch

   1. Download the jar file and copy into an empty folder

   2. Double-click the jar file. If you are unable to run the jar file by double-clicking it, open your terminal, cd into the folder where TalentNexus.jar is saved in, and then run the command java -jar TalentNexus.json.
      Expected: Shows the GUI with a set of sample contacts.

2. Saving window preferences

   1. Resize the window to an optimum size. Move the window to a different location. Close the window.

   2. Re-launch the app by double-clicking the jar file.
      Expected: The most recent window size and location is retained.

Deleting a recruit

1. Deleting a recruit while all recruits are being shown

   1. Prerequisites: Ensure you start the application with fresh sample data. List all recruits using the list command. There exists multiple recruits in the list. Perform the following test cases sequentially.

   2. Test case: delete 0
      Expected: No recruit is deleted. Error details shown in the status message.

   3. Test case: delete 1
      Expected: First recruit named "Alex Yeoh" is deleted from the list. Details of the deleted contact shown in the status message.

   4. Test case: Copy the UUID of the recruit "Bernice Yu" by clicking on the copy button besides this recruit's UUID. Execute delete <BERNICE_UUID>, replacing <BERNICE_UUID> with the actual UUID of this recruit by pasting it.
      Expected: Recruit "Bernice Yu" with UUID <BERNICE_UUID> is deleted from the list. Details of the deleted contact shown in the status message.

   5. Test case: delete
      Expected: error message stating that command format is invalid, together with information about the usage of the delete command is shown.

Exporting recruits

1. Exporting recruits using the default path

   1. Prerequisites: Ensure the default export path is set in preferences.json.

   2. Test case: export
      Expected: A .csv file containing all recruits is created in the default export path.

2. Exporting recruits to a specified path

   1. Ensure the target directory exists and is writable.

   2. Test case: export C:\data\recruits.csv
      Expected: A file recruits.csv created at C:\data\recruits.csv.

Sorting recruits

1. Sorting recruits by a single field

   1. Prerequisites: List all recruits using the list command. Multiple recruits exist in the list with varying names, phones, emails, and addresses.

   2. Test case: sort
      Expected: All recruits are sorted by name in ascending order (A-Z). Success message shows "Recruits sorted by: name (ascending)".

   3. Test case: sort -n asc
      Expected: All recruits are sorted by name in ascending order. Same result as sort.

   4. Test case: sort -n
      Expected: All recruits are sorted by name in ascending order. When sort order is omitted, it defaults to ascending. Same result as sort -n asc.

   5. Test case: sort -n desc
      Expected: All recruits are sorted by name in descending order (Z-A). Success message shows "Recruits sorted by: name (descending)".

   6. Test case: sort -p asc
      Expected: All recruits are sorted by phone number in ascending order. Recruits with missing phone numbers appear first.

   7. Test case: sort -e desc
      Expected: All recruits are sorted by email in descending order.

   8. Test case: sort -a asc
      Expected: All recruits are sorted by address in ascending order.

2. Sorting recruits by multiple fields

   1. Prerequisites: Multiple recruits exist with some sharing the same name but different phone numbers.

   2. Test case: sort -n asc -p desc
      Expected: Recruits are first sorted by name in ascending order. For recruits with identical names, they are further sorted by phone number in descending order. Success message shows "Recruits sorted by: name (ascending), phone (descending)".

   3. Test case: sort -n -p desc
      Expected: Same as above. When sort order is omitted for -n, it defaults to ascending.

   4. Test case: sort -n -p -e
      Expected: Recruits are sorted with three levels of priority: first by name, then by phone, then by email (all ascending, since order is omitted for all fields).

3. Handling identical values during sorting

   1. Prerequisites: Create multiple recruits with the exact same name (e.g., "John Doe").

   2. Test case: sort -n asc
      Expected: When all names are identical, the relative order of recruits is preserved from their state before sorting (stable sort behavior). The order is deterministic.

   3. Note: If recruits have identical values for the primary sort field, their order is maintained unless a secondary sort criterion is specified.

4. Invalid sort commands

   1. Test case: sort -x asc
      Expected: Error message indicating invalid command format. No sorting occurs.

   2. Test case: sort -n invalid
      Expected: Error message indicating invalid command format. No sorting occurs.

   3. Test case: sort -n -n asc
      Expected: Error message indicating duplicate prefix. No sorting occurs.

Undoing and redoing operations

1. Prerequisites: Ensure you start the application with fresh sample data. Then perform the following test cases sequentially.

2. Test case: `undo`<br>
   Expected: an error message stating that there are no operations that can be undone.

3. Test case: `clear -confirm`<br>
   Expected: all recruits are deleted.

4. Test case: `undo`<br>
   Expected: deletion of all recruits are undone.

5. Test case: `redo`<br>
   Expected: deletion of all recruits is performed again, all recruits are deleted.

6. Test case: `redo`<br>
   Expected:  an error message stating that there are no operations that can be redone.

Editing a recruit

1. Overwriting, appending to, deleting from and updating of primary attributes of a recruit

   1. Prerequisites: Ensure you start the application with fresh sample data. Then perform the following test cases sequentially.

   2. Test case: edit 1 n/Aylex Yo
      Expected: success message stating that the name of the first recruit in the list has been changed from "Alex Yeoh" to "Aylex Yo".

   3. Test case: edit 1 -ap p/99999999 e/alex@alex.com
      Expected: success message stating that the phone number 99999999 and the email address alex@alex.com have been added to the first recruit's phone number and email address list respectively.

   4. Test case: edit 1 -primary p/
      Expected: error message stating that all specified attributes must not be empty

   5. Test case: edit 1 -primary p/99999999
      Expected: success message stating that the first recruit's primary phone number has been changed from 87438807 to 99999999.

   6. Test case: edit 1 -rm p/99999999
      Expected: success message stating that the number 99999999 has been removed from the first recruit's phone number.