AB-3 Developer Guide

---

Acknowledgements

{ list here sources of all reused/adapted ideas, code, documentation, and third-party libraries -- include links to the original source as well }

---

Setting up, getting started

Refer to the guide Setting up and getting started.

---

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, PersonListPanel, 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 ca 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 Person 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 a example.

How the Logic component works:

1. When Logic is called upon to execute a command, it is passed to a MapletParser 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, a object of one of its subclasses e.g., DeleteCommand) which is executed by the LogicManager.
3. The command ca communicate with the Model when it is executed (e.g. to delete a person).
   Note that although this is shown as a single step in the diagram above (for simplicity), in the code it ca 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 MapletParser class creates a 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 MapletParser returns back as a Command object.
• All XYZCommandParser classes (e.g., AddCommandParser, DeleteCommandParser, ...) inherit from the Parser interface so that they ca be treated similarly where possible e.g, during testing.

Model component

API : Model.java

The Model component,

• stores the Maplet data i.e., all Attraction, Itinerary, and Location objects.
• exposes unmodifiable ObservableLists for attractions, itineraries, and locations so that the UI automatically updates when the data changes.
• stores a UserPrefs object that represents the user’s preferences. This is exposed to the outside as a ReadOnlyUserPrefs object.
• 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,

• ca save both Maplet data and user preference data in JSON format, and read them back into corresponding objects.
• inherits from both MapletStorage and UserPrefStorage, which means it ca 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.

---

Implementation

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

Location management feature

The location management feature lets users group attractions under named locations so that related places stay together.

Current implementation

• AddLocationCommand, EditLocationCommand, and DeleteLocationCommand handle the respective commands. Their parsers enforce the ln/ prefix, the presence of at least one attraction index where needed, and a valid action/ value for edits.
• Location, LocationName, and UniqueLocationList represent the domain model. A Location wraps a LocationName and a set of attraction Names.
• Model#addLocation, Model#setLocation, Model#deleteLocation, and Model#hasLocationName delegate to Maplet, which maintains the UniqueLocationList. Model#deleteLocation, and Model#hasLocationName delegate to Maplet, which maintains the UniqueLocationList.
• Persistence is handled by JsonSerializableMaplet and JsonAdaptedLocation, which validate that every referenced attraction exists when reading from disk.
• LocationListPanel and LocationCard render the list of locations in the UI.

When a user executes addlocation ln/Singapore i/1 i/2:

1. MapletParser chooses AddLocationCommandParser, which tokenises the prefixes and converts each i/ value into an Index.
2. The command retrieves each attraction from Model#getFilteredAttractionList() and collects their Name values, rejecting out-of-range indexes or duplicates.
3. A new Location is created. Location enforces that at least one attraction is present and throws if the set is empty.
4. Model#hasLocationName prevents duplicate location names before calling Model#addLocation, which stores the entry in the UniqueLocationList.

When a user executes editlocation ln/Singapore action/ADD i/3:

1. MapletParser chooses EditLocationCommandParser, which tokenises the prefixes, checks that each is present exactly once, and converts i/ into an Index.
2. EditLocationCommand obtains the attraction at index 3 from Model#getFilteredAttractionList() to avoid editing attractions that are currently hidden from the user.
3. The command locates the existing Location by name, clones its attraction Name set, and either adds or removes the selected attraction depending on the requested action. Attempting to add a duplicate, remove a non-existent attraction, or leave the location empty raises a CommandException.
4. A new Location is constructed with the updated attraction set and persisted via Model#setLocation, ensuring that list observers are notified of the change.

The deletelocation command follows a similar flow but calls Model#deleteLocation(LocationName) to remove the entry while leaving the attractions untouched.

Design considerations

• By storing attraction Names instead of full attraction objects, locations stay synchronized with the attraction list without duplicating data.
• All persistence checks happen during deserialization (JsonAdaptedLocation#toModelType) so invalid data never reaches the model.
• Re-creating Location instances during edits keeps them immutable, which simplifies UI updates and equality checks while preventing shared mutable state between locations and attractions.

Itinerary management feature

The itinerary management feature allows users to create travel plans by grouping attractions into named itineraries.

Current implementation

• AddItineraryCommand and DeleteItineraryCommand handle the respective commands. Their parsers enforce the n/ prefix for itinerary names and ai/ prefix for the attraction indexes.
• Itinerary, ItineraryName, and UniqueItineraryList represent the domain model. An Itinerary wraps an ItineraryName, a creation timestamp (LocalDateTime), and a UniqueAttractionList of attractions.
• Model#addItinerary, Model#deleteItinerary, Model#hasItinerary, and Model#setItinerary delegate to Maplet, which maintains the UniqueItineraryList.
• Persistence is handled by JsonSerializableMaplet and JsonAdaptedItinerary, which store attractions as names and validate that every referenced attraction exists.
• ItineraryListPanel and ItineraryCard render the list of itineraries in the UI. When an itinerary is selected, its associated attractions are displayed in a separate panel managed by MainWindow#showItineraryDetails.

When a user executes additinerary n/Singapore Trip ai/1 ai/2:

1. MapletParser chooses AddItineraryCommandParser, which tokenizes the prefixes and converts each ai/ value into an Index.
2. The command retrieves each attraction from Model#getFilteredAttractionList() and collects the Name values, rejecting out-of-range indexes or duplicate references.
3. A new Itinerary is created with the current timestamp (LocalDateTime.now()). The Itinerary constructor validates that attractions are unique and stores them in a UniqueAttractionList.
4. Model#hasItinerary prevents duplicate itinerary names before calling Model#addItinerary, which stores the entry in the UniqueItineraryList.

The deleteitinerary command follows a similar flow but uses an index-based approach. It retrieves the itinerary from Model#getFilteredItineraryList() and calls Model#deleteItinerary(Itinerary) to remove it while leaving the referenced attractions intact.

Design considerations

• Itineraries reference actual Attraction objects rather than just names, allowing direct access to attraction details without additional lookups.
• Each itinerary maintains its own UniqueAttractionList, enforcing that an attraction can only appear once per itinerary.
• The UI selection handler pattern enables interactive itinerary exploration, where selecting an itinerary displays its attractions in a separate panel.

[Proposed] Undo/redo feature

Proposed Implementation

The proposed undo/redo mechanism is facilitated by VersionedMaplet. It extends Maplet with an undo/redo history, stored internally as a mapletStateList and currentStatePointer. Additionally, it implements the following operations:

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

These operations are exposed in the Model interface as Model#commitMaplet(), Model#undoMaplet() and Model#redoMaplet() respectively.

Given below is a 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 VersionedMaplet will be initialized with the initial Maplet state, and the currentStatePointer pointing to that single Maplet state.

Step 2. The user executes delete 5 command to delete the 5th person in the Maplet. The delete command calls Model#commitMaplet(), causing the modified state of the Maplet after the delete 5 command executes to be saved in the mapletStateList, and the currentStatePointer is shifted to the newly inserted Maplet state.

Step 3. The user executes add n/David …​ to add a new person. The add command also calls Model#commitMaplet(), causing another modified Maplet state to be saved into the mapletStateList.

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

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

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

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

Step 5. The user then decides to execute the command list. Commands that do not modify the Maplet, such as list, will usually not call Model#commitMaplet(), Model#undoMaplet() or Model#redoMaplet(). Thus, the mapletStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitMaplet(). Since the currentStatePointer is not pointing at the end of the mapletStateList, all Maplet 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 activities 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 Maplet.

  • 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 person being deleted).
  • Cons: We must ensure that the implementation of each individual command are correct.

{more aspects and alternatives to be added}

[Proposed] Data archiving

{Explain here how the data archiving feature will be implemented}

Planned Enhancements

1. Editing of itinerary Currently there is no way to conveniently edit an itinerary. The use will have to create a new itinerary using the additinerary command with the desired attractions and delete the old itinerary. This can become tedious especially when the itinerary contains many attractions. We plan to add an edititinerary command that takes in a ITINERARY_NAME, action/ACTION and ai/ATTRACTION_INDEX parameter. This works similarly to editlocation where you can add/remove attractions from a corresponding location.

2. Viewing comments Currently you can view comments by clicking on the "View Comments" button with a mouse, or using the tab key to select the button and pressing enter. This can be rather inconvenient especially when the attraction list gets very large. To resolve we plan to add a viewcomment command which takes in an INDEX parameter and opens the comment window for the attraction corresponding to INDEX.

3. Switch tabs Currently you can switch between attraction, location and itinerary tabs by either clicking on the tab buttons with a mouse, or using the tab key to select the buttons and navigating with arrows keys. This is inconvenient and unintuitive for users and can be improved on by adding a switch command which takes in a KEYWORD parameter. This KEYWORD parameter can take on three values: "attraction", "location" and "itinerary" and allow the user to switch between the different tabs through commands.

---

Documentation, logging, testing, configuration, dev-ops

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

---

Appendix: Requirements

Product scope

Target user profile:

This product is aimed at individuals planning to go overseas/frequent travellers.

• has a need to keep track of a large amount of relevant locations and attractions at the locations
• prefer desktop apps over other types
• ca type fast
• prefers typing to mouse interactions
• is reasonably comfortable using CLI apps
• needs to draft a suitable trip pla that stays within budget
• wants detailed information on locations of interest

Value proposition: manage locations of interest faster tha typical travel management sites

Maplet ca store useful information on locations and attractions:

For attractions (within the location):

1. Opening hours
2. Price
3. Rating

Attractions are grouped by locations and have activities associated with them.

User stories

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

{More to be added}

Use cases

(For all use cases below, the System is the Maplet and the Actor is the user, unless specified otherwise)

Use case: UC1 - List attractions

MSS

1. User chooses to list attractions at a location

2. Maplet shows a list of attractions at the location

   Use case ends.

Extensions

• 1a. User does not specify location

  • 1a1. Maplet shows a list of all attractions

    Use case ends.

• 2a. The list is empty.

  Use case ends.

Use case: UC2 - Add attraction

MSS

1. User chooses to add attraction

2. User enters the required attraction details

3. Maplet adds new attraction to list

   Use case ends.

Extensions

• 2a. Details are in the wrong format

  • 2a1. Maplet prompts the user for correct format

  • 2a2. User enters correct attraction details

    Steps 2a1-2a2 are repeated until the details entered are correct.
    Use case resumes at step 3.

Use case: UC3 - Delete attraction

MSS

1. User chooses to list attractions (UC1) to see index of attractions

2. User chooses to delete an attraction in the list

3. User enters index of attraction to delete

4. Maplet deletes the attraction

   Use case ends.

Extensions

• 3a. The given index is invalid.

  • 3a1. Maplet prompts the user for valid index

  • 3a2. User enters valid index

    Steps 3a1-3a2 are repeated until index entered is valid.
    Use case resumes at step 4.

Use case: UC4 - Find attraction

MSS

1. User chooses to find a attraction with a keyword

2. User enters keyword

3. Maplet shows a list of attractions related to keyword

   Use case ends.

Extensions

• 2a. No keyword is given.

  • 2a1. Maplet prompts the user for valid keyword

  • 2a2. User enters valid keyword

    Steps 2a1-2a2 are repeated until keyword entered is valid.
    Use case resumes at step 3.

• 3a. The list is empty

  Use case ends.

Use case: UC5 - Edit attraction

MSS

1. User chooses to list attractions (UC1) to see index of attractions

2. User chooses to edit an attraction in the list

3. User enters index and details of attraction to edit

4. Maplet updates the attraction details

   Use case ends.

Extensions

• 3a. The given index is invalid.

  • 3a1. Maplet prompts the user for valid index

  • 3a2. User enters valid index

    Steps 3a1-3a2 are repeated until index entered is valid.
    Use case resumes at step 4.

• 3b. Details are in the wrong format

  • 3b1. Maplet prompts the user for correct format

  • 3b2. User enters correct attraction details

    Steps 3b1-3b2 are repeated until the details entered are correct.
    Use case resumes at step 4.

Use case: UC6 - Sort attractions

MSS

1. User chooses to sort attractions by a criteria

2. User enters criteria

3. Maplet shows a list of attractions sorted by criteria

   Use case ends.

Extensions

• 2a. Wrong criteria format is given.

  • 2a1. Maplet prompts the user for valid criteria

  • 2a2. User enters valid criteria

    Steps 2a1-2a2 are repeated until criteria entered is valid.
    Use case resumes at step 3.

• 3a. The list is empty

  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 be able to hold up to 1000 attractions without a noticeable sluggishness in performance for typical usage.
3. 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 tha using the mouse.
4. When retrieving or saving location data, the system should respond within 2 seconds.
5. When the user filters locations based on a order (distance, rating, …), the system should take less than 3 seconds
6. The system must should be able to handle 100 simultaneous users query without degradation
7. All user data (travel plans, ratings, reviews, …) should be stored securely in the database
8. The system should require user authentication before retrieve personal data
9. The system should be able to handle up to 1000 locations and user-content
10. New user should take less than 5 minutes to set up account and start using application’s features
11. User with disabilities should have access to all features

{More to be added}

Glossary

• Mainstream OS: Windows, Linux, Unix, MacOS
• Attraction: A single place of interest
• Activity: A thing to be done at a attraction
• Location: A location can contain any number of attractions
• Itinerary: An itinerary refers to a list of attractions to be visited, as well as the time spent at each attraction

---

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 a empty folder

   2. Double-click the jar file Expected: Shows the GUI with a set of sample contacts. The window size may not be optimum.

2. Saving window preferences

   1. Resize the window to a 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.

3. { more test cases …​ }

Deleting a person

1. Deleting a person while all persons are being shown

   1. Prerequisites: List all persons using the list command. Multiple persons in the list.

   2. Test case: delete 1
      Expected: First contact is deleted from the list. Details of the deleted contact shown in the status message. Timestamp in the status bar is updated.

   3. Test case: delete 0
      Expected: No person is deleted. Error details shown in the status message. Status bar remains the same.

   4. Other incorrect delete commands to try: delete, delete x, ... (where x is larger tha the list size)
      Expected: Similar to previous.

2. { more test cases …​ }

Saving data

1. Dealing with missing/corrupted data files

   1. {explain how to simulate a missing/corrupted file, and the expected behavior}

2. { more test cases …​ }