DeveloperGuide.adoc

CLIndar - Developer Guide

By: CS2103JAN2018-W13-B3      Since: Mar 2018      Licence: MIT

• 1. Introduction
• 2. Computer Setup
  • 2.1. Prerequisites
  • 2.2. Setup Procedure
  • 2.3. Setup Verification
  • 2.4. Configurations to Do Before Writing Code
• 3. Design
  • 3.1. Architecture
  • 3.2. UI Component
  • 3.3. Logic Component
  • 3.4. Model Component
  • 3.5. Storage Component
  • 3.6. Commons Classes
• 4. Implementation
  • 4.1. Activity
  • 4.2. GUI
  • 4.3. Undo/Redo feature
  • 4.4. Storage for Task and Event
  • 4.5. Logging
  • 4.6. Configuration
• 5. Documentation
  • 5.1. Editing Documentation
  • 5.2. Publishing Documentation
  • 5.3. Converting Documentation to PDF format
• 6. Testing Procedures
  • 6.1. Methods for Running Tests
  • 6.2. Test Types
  • 6.3. Troubleshooting Test
• 7. Dev Ops
  • 7.1. Build Automation
  • 7.2. Continuous Integration
  • 7.3. Coverage Reporting
  • 7.4. Documentation Previews
  • 7.5. Release Creation
  • 7.6. Dependencies Management
• Appendix A: Suggested Programming Tasks to Get Started
  • A.1. Improving each component
  • A.2. Creating a new command: remark
• Appendix B: Product Scope
  • B.1. Feature contribution
• Appendix C: User Stories

1. Introduction

CLIndar is a desktop application that helps university computing students to manage their schedules. CLIndar is Common-Line Interface (CLI) based and uses Linux-style commands, which computing students are familiar with.

This guide provides information on the core functionalities of CLIndar and their implementation, so that a developer can get started customising and contributing to the application.

Below is an overview of this guide:

• Computer Setup

• Design

• Implementation

• Documentation

• Testing Procedures

• Dev Ops

• Appendices

2. Computer Setup

This section describes the steps needed to set up your computer before you can start developing this application further with your own code.

2.1. Prerequisites

The following must be installed in your computer before you can begin using the application:

1. JDK 1.8.0_60 or later

   ℹ️	Having any Java 8 version is not enough. This app will not work with earlier versions of Java 8.

2. IntelliJ IDE

   ℹ️	IntelliJ by default has Gradle and JavaFx plugins installed. Do not disable them. If you have disabled them, go to File > Settings > Plugins to re-enable them.

2.2. Setup Procedure

Do the following steps to set up the project in your computer.

Step 1: Fork this repo, and clone the fork to your computer.

To fork the repo, click the button circled below.

Figure 1. Forking this repo

Then, open Git Bash. Change the current working directory to the location where you want the cloned directory to be made. Type the following:

git clone https://github.com/YOUR-USERNAME/main.git

If the clone was successful, a new sub-directory titled 'main' appears on your local drive. This directory contains the files and metadata that Git requires to maintain the changes you make to the source files.

The following should appear if git clone https://github.com/YOUR-USERNAME/main.git at C:/Users/temp folder is executed.

Figure 2. Finding cloned directory

Step 2: Open IntelliJ. If you are not in the welcome screen, click File > Close Project to close the existing project dialog first, as shown in the picture below.

Figure 3. Closing current project in IntelliJ

Step 3: Set up the correct JDK version for Gradle using the following steps, as illustrated by the pictures.

Step 3a: Click Configure > Project Defaults > Project Structure.

Figure 4. Configuring IntelliJ settings

Step 3b: Go to the Project tab and under Project SDK section, click New…​. Find the directory of the JDK, and then click OK.

Figure 5. Setting up JDK

Step 4: Click Import Project.

Figure 6. Importing project to IntelliJ

Step 5: Locate the build.gradle file in the main folder that you have cloned and select it. Click OK.

Figure 7. Locating build.gradle file

Step 6: In the Import Project from Gradle that appears, click OK again.

Step 7: Open the Terminal and run the command gradlew processResources (Mac/Linux: ./gradlew processResources). It should finish with the BUILD SUCCESSFUL message.

This will generate all resources required by the application and tests.

2.3. Setup Verification

Do the following steps to verify that the project has been successfully set up in your computer:

1. Run the seedu.address.MainApp and try a few commands.

2. Run the tests to ensure that they all pass.
   
   

2.4. Configurations to Do Before Writing Code

After you set up the project in your own computer, you still need to do the the configurations described in the following sections before you can start developing this application further with your own code.

2.4.1. Coding Style Configuration

This project follows oss-generic coding standards. IntelliJ’s default style is mostly compliant with ours but it uses a different import order from ours. To rectify, do the following steps:

1. Go to File > Settings…​ (Windows/Linux), or IntelliJ IDEA > Preferences…​ (macOS).

2. Select Editor > Code Style > Java.

3. Click on the Imports tab.

   • For Class count to use import with '*' and Names count to use static import with '*': Set to 999 to prevent IntelliJ from contracting the import statements.

   • For Import Layout: Set the order to be import static all other imports, import java.*, import javax.*, import org.*, import com.*, import all other imports. Add a <blank line> between each import.

After you do the steps above, the Settings window should appear as shown in the picture below.

Figure 8. Configuring IntelliJ settings for import order

Optionally, you can follow the UsingCheckstyle.adoc document to configure Intellij to check style-compliance as you write the code.

2.4.2. Documentation Updating

After forking the repo, links in the documentation will still point to the CS2103JAN2018-W13-B3/main repo. If you plan to develop this as a separate product, you should replace the URL in the variable repoURL in DeveloperGuide.adoc and UserGuide.adoc with the URL of your fork.

2.4.3. CI Setup

Travis needs to be set up to perform Continuous Integration (CI) for your fork. See UsingTravis.adoc to learn how to set it up.

After setting up Travis, you can optionally set up coverage reporting for your team fork (see UsingCoveralls.adoc).

ℹ️	Coverage reporting could be useful for a team repository that hosts the final version but it is not that useful for your personal fork.

Optionally, you can set up AppVeyor as a second CI (see UsingAppVeyor.adoc).

ℹ️	Having both Travis and AppVeyor ensures your App works on both Unix-based platforms and Windows-based platforms (Travis is Unix-based and AppVeyor is Windows-based).

2.4.4. Steps to Get Started with Coding

Follow the steps below when you are ready to start coding:

1. Get some sense of the overall design by reading Section 3.1, “Architecture”.

2. Take a look at Appendix A, Suggested Programming Tasks to Get Started.
   
   

3. Design

This section describes how the features in this application are implemented internally.

3.1. Architecture

The high-level design of this application is illustrated in Figure 9 below.

Figure 9. Architecture diagram

Given below is a quick overview of each component.

💡	The .pptx files used to create diagrams in this document can be found in the diagrams folder. To update a diagram, modify the diagram in the pptx file, select the objects of the diagram, and choose Save as picture.

Main has only one class called MainApp. It is responsible for:

• at app launch: initializing other components in the correct sequence and connecting them up with each other; and

• at shut down: shutting down other components and invoking cleanup method where necessary.

Commons represents a collection of classes used by multiple other components. Two of those classes play important roles at the architecture level:

• EventsCenter: This class (written using Google’s Event Bus library) is used by components to communicate with other components using events (i.e. a form of Event Driven design).

• LogsCenter: This class is used by many classes to write log messages to the App’s log file.

The rest of the application consists of four components:

• UI: This component controls the UI of the application.

• Logic: This is the command executor.

• Model: This component holds the data of the App in-memory.

• Storage: This component reads data from, and writes data to, the hard disk.

Each of the four components:

• defines its API in an interface with the same name as the component; and

• exposes its functionality using a {Component Name}Manager class.

For example, the Logic component defines its API in the Logic.java interface and exposes its functionality using the LogicManager.java class. Figure 10 below is an overview of the Logic component.

Figure 10. The API of the Logic component

Events-Driven Nature of the Design

Figure 11 below shows how the components interact in a scenario where the user issues the command delete 1.

Figure 11. Component interactions for delete 1 command (part 1)

ℹ️	Note how the Model simply raises a DeskBoardChangedEvent when the Desk Board data are changed, instead of asking the Storage to save the updates into the hard disk.

Figure 12 below shows how the EventsCenter reacts to that event, which eventually results in the updates being saved to the hard disk and the status bar of the UI being updated to reflect the 'Last Updated' time.

Figure 12. Component interactions for delete 1 command (part 2)

ℹ️	Note how the event is propagated through the EventsCenter to the Storage and UI without Model having to be coupled to either of them. This is an example of how this Event Driven approach helps us reduce direct coupling between components.

The sections below give more details of each component.

3.2. UI Component

Figure 13 below shows the architecture diagram of the UI component.

Figure 13. Structure of the UI component

API : Ui.java

The UI consists of a MainWindow that is made up of parts e.g.CommandBox, ResultDisplay, TaskListPanel, EventListPanel, StatusBarFooter, BrowserPanel etc. All these, including the MainWindow, inherit from the abstract UiPart class.

The UI component uses 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;

• binds itself to some data in the Model so that the UI can auto-update when data in the Model change; and

• responds to events raised from various parts of the App and updates the UI accordingly.

3.3. Logic Component

Figure 14 below shows the architecture diagram of the Logic component.

Figure 14. Structure of the Logic Component

Finer details concerning XYZCommand and Command in Figure 14, “Structure of the Logic Component” in Figure 15 below.

Figure 15. Structure of commands in the Logic component

API : Logic.java

The following describes the sequence of events executed by the Logic component:

• Logic uses the DeskBoardParser class to parse the user command.

• This results in a Command object which is executed by the LogicManager.

• The command execution can affect the Model (e.g. adding a activity) and/or raise events.

• The result of the command execution is encapsulated as a CommandResult object which is passed back to the Ui.

Given below is the Sequence Diagram for interactions within the Logic component for the execute("rm task 1") API call.

Figure 16. Interactions inside the Logic component for the rm task 1 command

3.4. Model Component

Figure 17 below shows the architecture diagram of the Model component.

Figure 17. Structure of the Model component

API : Model.java

The Model component:

• stores a UserPref object that represents the user’s preferences,

• stores the Desk Board data;

• uses two classes to store information about Event and Task separately;

• exposes an unmodifiable ObservableList<Activity> 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; and

• does not depend on any of the other three components.

3.5. Storage Component

Figure 18 below shows the structure of the Storage component.

Figure 18. Structure of the Storage component

API : Storage.java

The Storage component saves and reads back:

• UserPref objects in json format, and

• desk board data in xml format.

3.6. Commons Classes

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

4. Implementation

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

4.1. Activity

Activity resides in the Model component of the application. It is an important class in this application as it represents each entry in the desk board. In CLIndar, an entry in the desk board can be either a Task or an Event.

4.1.1. Current implementation

Figure 19 below shows the relationship between Activity and its relevant components.

Figure 19. Class diagram for Activity

As shown above, Activity is a superclass for Task and Event. Activity is made abstract so that it cannot be instantiated. This is because an entry in the desk board must be either a Task or an Event and cannot simply be an Activity.

Adding a task

Task is one of the two types of entries in the desk board in CLIndar. Task represents a piece of work to be done by a certain deadline. Once the Task has been done by user, it can be mark as completed in the application.

Figure 20 below shows how Task is represented in the application.

Figure 20. UML class diagram for Task

A brief description of each of the attributes of Task is given below:

• name: name of the task. This attribute is compulsory.

• dueDateTime: deadline of the task which includes date and time. This attribute is compulsory.

• remark: a short description or any other comments pertaining to the task. This attribute is optional.

• tags: groupings for the task. This attribute is optional and a Task object can have multiple tags.

A Task object can be added to the desk board through the use of the TaskCommand. A TaskCommand is associated with a Task object to be added. When a TaskCommand object calls the method executeUndoableCommand(), the Task object is added into UniqueActivityList in the DeskBoard. Note that the Task object will not be added if an equivalent Task is found in the desk board or the name or dueDateTime field is left empty.

The following is a snippet of code for TaskCommand 's executeUndoableCommand() method.

    public CommandResult executeUndoableCommand() throws CommandException {
        requireNonNull(model);
        try {
            model.addActivity(toAdd);
            return new CommandResult(String.format(MESSAGE_SUCCESS, toAdd));
        } catch (DuplicateActivityException e) {
            throw new CommandException(MESSAGE_DUPLICATE_TASK);
        }
    }

Once the task is successfully added, it will be reflected in the CLIndar GUI itself.

Adding an event

Event is the second and last type of entries in the desk board in CLIndar. Event represents an activity with fixed start and end times, such as a test, doctor appointment etc.

Figure 19 below shows how Event is implemented in the application.

Figure 21. UML Class Diagram for Event

A brief description of each of the attributes of Event is given below:

• name: name of the event. This attribute is compulsory.

• startDateTime: start date and time of the event. This attribute is compulsory.

• endDateTime: end date and time of the event. This attribute is compulsory.

• location: location of the event. This attribute is optional.

• remark: a short description or any other comments pertaining to the event. This attribute is optional.

• tags: groupings for the event. This attribute is optional and an Event object can have multiple tags.

An Event object can be added to the desk board through the use of the EventCommand. The way Event objects are added to UniqueActivityList is the same as Task objects. Note that the Event object will not be added if an equivalent Event is found in the desk board or the name, startDateTime or endDateTime field is left empty.

Once the Event is successfully added, it will be reflected in the CLIndar GUI itself.

Autosorting feature

In the GUI, the Task and Event objects will always be shown sorted in terms of their dueDateTime and startDateTime respectively. This is achieved through the UniqueActivityList which contains a list of unique activities which is either a Task or an Event stored in an internalList. Each time an Activity is added to or edited in the UniqueActivityList, internalList will be sorted according to its dateTime attribute. Note dateTime refers to dueDateTime for Task and startDateTime for Event.

Following is a snippet which illustrates the function of UniqueActivityList:

    private final ObservableList<Activity> internalList = FXCollections.observableArrayList();

    /...some code.../

    public void add(Activity toAdd) throws DuplicateActivityException {
        requireNonNull(toAdd);
        if (contains(toAdd)) {
            throw new DuplicateActivityException();
        }
        internalList.add(toAdd);
        Collections.sort(internalList, dateTimeComparator);
    }

Removing a task or an event

Task and Event objects can be removed through the use of the RemoveCommand by specifying the Task or Event and the index of the task/event reflected in the GUI.

The following snippet shows the executeUndoableCommand() of the RemoveCommand class. UniqueActivityList resides in the Model will be updated by having activityToDelete deleted from it. If the index of an activity is not found, an ActivityNotFoundException will be thrown.

    public CommandResult executeUndoableCommand() {
        requireNonNull(activityToDelete);
        try {
            model.deleteActivity(activityToDelete);
        } catch (ActivityNotFoundException pnfe) {
            throw new AssertionError("The target activity cannot be missing");
        }

        /...some code.../
    }

If RemoveCommand is successful, the relevant Task or Event at the specified index will be removed which will be reflected in the GUI.

Completing a task

Task objects can be completed through the use of the CompleteCommand by specifying the Task’s index reflected in the GUI. Note that `CompleteCommand can only be applied to Task objects.

Below is a snippet of how the executeUndoableCommand() of CompleteCommand updates the respective task to completed.

    public CommandResult executeUndoableCommand() {
        requireNonNull(activityToComplete);
        try {
            Activity completedActivity = activityToComplete.getCompletedCopy();
            model.updateActivity(activityToComplete, completedActivity);
        } catch (ActivityNotFoundException pnfe) {
            throw new AssertionError("The target activity cannot be missing");
        } catch (DuplicateActivityException dae) {
            throw new AssertionError("The completed activity cannot be duplicated");
        }
        return new CommandResult(String.format(MESSAGE_COMPLETE_TASK_SUCCESS, activityToComplete));
    }

If CompleteCommand is successful, 'Uncompleted' will be replaced by 'Completed' in the GUI.

4.1.2. Design considerations

There are two ways to represent tasks and events in the application. The following shows the pros and cons for each alternative:

• Alternative 1 (Current Choice): Use a single class Activity as a superclass for Task and Event.
  

  • Pros: As both Task and Event can be treated equally in most contexts other than their creation, this can simplify the code significantly.

  • Cons: It might be a harder to retrieve information as Event contains extra attributes that Task does not have. Extra accessor methods will also be required for Event.

• Alternative 2 : Simply have two different class Task and Event.

  • Pros: There is a clear distinction between the two classes.

  • Cons: We will need to write codes for classes and methods related to Task and Event separately, when these could have been simplified by having classes and methods related to the superclass only.
    
    

4.2. GUI

This section describes implementation of features related to the GUI.

4.2.1. Current implementation

There are two types of commands related to the GUI: list and overdue. The following sections will describe the implementation for each comman.

Listing of tasks and events

A single Task or Event is displayed using a TaskListCard or EventListCard respectively. The list of all the Task objects added by the user is then displayed using the TaskListPanel, while Event objects added by user are displayed using EventListPanel. Below are examples of a TaskListCard and an EventListCard.

Figure 22. TaskListCard example

Figure 23. EventListCard example

ListCommand allows the user to only view Task only, Event only or both in the GUI.

The following snippet shows how execute() of ListCommand displays Task and/or Event objects in the GUI. If an invalid request for ListCommand happens, a CommandException will be thrown.

    public CommandResult execute() throws CommandException {

        switch(commandRequest)  {
        case "task":
            EventsCenter.getInstance().post(new ShowTaskOnlyRequestEvent());
            return new CommandResult(MESSAGE_SUCCESS_TASK);
        case "event":
            EventsCenter.getInstance().post(new ShowEventOnlyRequestEvent());
            return new CommandResult(MESSAGE_SUCCESS_EVENT);
        /..some code../

        default:
            throw new CommandException(String.format(Messages.MESSAGE_INVALID_LIST_REQUEST, commandRequest));
        }
    }

If ListCommand is successful:

• list will show only Task objects;

• list event will show only Event objects; and

• list will show both Task and Event objects.
  
  

Overdue

Overdue tasks can be viewed through the use of the OverdueCommand. Note that the OverdueCommand only lists down overdue tasks; overdue events are marked as completed automatically.

OverdueCommand makes use of the LocalDateTime class in Java to check if an ongoing task becomes overdue or not.

There will be a class in the Model component, which has access to the UniqueActivityList class in that component. The class will go through the UniqueActivityList and obtain the dueDateTime of Task, and the end DateTime of Event. It will then perform a check of the DateTime with LocalDateTime.now(). If a Task is overdue, it will be marked so in the GUI. If the current date and time is past an Event s `endDateTime, the Event will be marked as completed.

4.2.2. Design considerations

This section describes various design considerations related to the GUI features. For each aspect, we will discuss the 2 alternatives considered and the pros and cons for each alternative.

Aspect: Implementation of ListCommand

• Alternative 1: Have 1 panel which will display the 2 classes.

  • Pros: The coding required for this approach is much lesser.

  • Cons: The UI will be messier and less appealing.

• Alternative 2 (current choice): Have 2 panels which will display the 2 classes separately.

  • Pros: The backend coding will be neater as the 2 classes do not have the same number of compulsory information tags. The design of the UI will be much more intuitive too.

  • Cons: A lot more coding is required to create the 2 separate panel.
    
    

We preferred the second alternative as it adheres more closely with fundamental design principles. The GUI has to be made as intuitive as possible to bring convenience and comfort to the user. As such, the second alternative is definitely the preferred approach here.

Aspect: Implementation of OverdueCommand

• Alternative 1: Put the checking method in the UniqueActivityList class.

  • Pros: There will be one fewer classes and it will be easier for the developer to understand the code.

  • Cons: This violates Single Responsibility Principle (SRP). The UniqueAcitivtyList class should not perform the checking.

• Alternative 2: Use Google Maps API to obtain current time.

  • Pros: LocalDateTime.now() is reliant on system clock. Thus, if the system clock is in error, tasks that are overdue will not be marked correctly.

  • Cons: Reliant on Google Maps API, and might be difficult for the developer to understand.
    
    

4.3. Undo/Redo feature

The current implementation and design considerations for the undo/redo feature are explained in this section.

4.3.1. Current implementation

The undo/redo mechanism is facilitated by an UndoRedoStack, which resides inside LogicManager. It supports undoing and redoing of commands that modifies the state of the desk board (e.g. add, edit). Such commands will inherit from UndoableCommand.

UndoRedoStack only deals with UndoableCommands. Commands that cannot be undone will inherit from Command instead. The following diagram shows the inheritance diagram for commands:

Figure 24. Class Diagram of a Logic Command

As you can see from the diagram, UndoableCommand adds an extra layer between the abstract Command class and concrete commands that can be undone, such as the DeleteCommand. Note that extra tasks need to be done when executing a command in an undoable way, such as saving the state of the desk board before execution. UndoableCommand contains the high-level algorithm for those extra tasks while the child classes implements the details of how to execute the specific command. Note that this technique of putting the high-level algorithm in the parent class and lower-level steps of the algorithm in child classes is also known as the template pattern.

Commands that are not undoable are implemented this way:

public class ListCommand extends Command {
    @Override
    public CommandResult execute() {
        // ... list logic ...
    }
}

With the extra layer, the commands that are undoable are implemented this way:

public abstract class UndoableCommand extends Command {
    @Override
    public CommandResult execute() {
        // ... undo logic ...

        executeUndoableCommand();
    }
}

public class DeleteCommand extends UndoableCommand {
    @Override
    public CommandResult executeUndoableCommand() {
        // ... delete logic ...
    }
}

Suppose that the user has just launched the application. The UndoRedoStack will be empty at the beginning.

The user executes a new UndoableCommand, delete 5, to delete the 5th activity in the desk board. The current state of the desk board is saved before the delete 5 command executes. The delete 5 command will then be pushed onto the undoStack (the current state is saved together with the command).

As the user continues to use the program, more commands are added into the undoStack. For example, the user may execute add n/David …​ to add a new activity.

ℹ️	If a command fails its execution, it will not be pushed to the UndoRedoStack at all.

The user now decides that adding the activity was a mistake, and decides to undo that action using undo.

We will pop the most recent command out of the undoStack and push it back to the redoStack. We will restore the desk board to the state before the add command executed.

Figure 25. 'Undo' stack pops into the 'Redo' Stack

ℹ️	If the undoStack is empty, then there are no other commands left to be undone, and an Exception will be thrown when popping the undoStack.

The following sequence diagram shows how the undo operation works:

Figure 26. 'Undo' and 'Redo' Stack Sequence Diagram

The redo command does the exact opposite (pops from redoStack, pushes to undoStack, and restores the desk board to the state after the command is executed).

ℹ️	If the redoStack is empty, then there are no other commands left to be redone, and an Exception will be thrown when popping the redoStack.

The user now decides to execute a new command, clear. As before, clear will be pushed into the undoStack. This time the redoStack is no longer empty. It will be purged as it no longer make sense to redo the add n/David command (this is the behavior that most modern desktop applications follow).

Figure 27. Adding 'ClearCommand' to the 'Undo' Stack

Commands that are not undoable are not added into the undoStack. For example, list, which inherits from Command rather than UndoableCommand, will not be added after execution:

Figure 28. 'ListCommand' does not affect the 'Undo' Stack

The following activity diagram summarize what happens inside the UndoRedoStack when a user executes a new command:

Figure 29. Activity Diagram for 'Undo' and 'Redo'

4.3.2. Design considerations

This section describes various design considerations related to the implementation of undo/redo feature. For each aspect, we will discuss the 2 alternatives considered and the pros and cons for each alternative.

Aspect: Implementation of UndoableCommand

• Alternative 1 (current choice): Add a new abstract method executeUndoableCommand().

  • Pros: We will not lose any undone/redone functionality as it is now part of the default behaviour. Classes that deal with Command do not have to know that executeUndoableCommand() exist.

  • Cons: It will be hard for new developers to understand the template pattern.

• Alternative 2: Just override execute().

  • Pros: This does not involve the template pattern, easier for new developers to understand.

  • Cons: Classes that inherit from UndoableCommand must remember to call super.execute(), or lose the ability to undo/redo.

Aspect: Execution of undo and redo

• Alternative 1 (current choice): Save the entire desk board.

  • Pros: This is easy to implement.

  • Cons: There may be performance issues in terms of memory usage.

• Alternative 2: Make individual command know how to undo/redo itself.

  • Pros: This will use less memory (e.g. for delete, just save the activity being deleted).

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

Aspect: Type of commands that can be undone/redone

• Alternative 1 (current choice): Only include commands that modifies the desk board (add, clear, edit).

  • Pros: We only revert changes that are hard to change back (the view can easily be re-modified as no data are lost).

  • Cons: User might think that undo also applies when the list is modified (undoing filtering for example), only to realize that it does not do that, after executing undo.

• Alternative 2: Include all commands.

  • Pros: This might be more intuitive to the user.

  • Cons: User has no way of skipping such commands if he or she just want to reset the state of the desk board and not the view.

Additional Info: See our discussion here.

Aspect: Data structure to support the undo/redo commands

• Alternative 1 (current choice): Use separate stack for undo and redo.

  • Pros: This is easy for new Computer Science student undergraduates to understand, who are likely to be the new incoming developers of our project.

  • Cons: Logic is duplicated twice. For example, when a new command is executed, we must remember to update both HistoryManager and UndoRedoStack.

• Alternative 2: Use HistoryManager for undo/redo.

  • Pros: We do not need to maintain a separate stack, and just reuse what is already in the codebase.

  • Cons: This requires dealing with commands that have already been undone: We must remember to skip these commands. This violates SRP and Separation of Concerns as HistoryManager now needs to do two different things.

4.4. Storage for Task and Event

This section describes the implementation and design considerations for the storage of Task and Event.

4.4.1. Current implementation

Storing of Task and Event data is managed by StorageManager within the Storage component. Task and Event is converted to XmlAdaptedTask and XmlAdaptedEvent respectively to be stored in a .xml file.

4.4.2. Design considerations

The application deals with 2 main classes: Task and Event. Hence, when the data is stored, there is a need for differentiation between these 2 classes. There are 2 possible implementations to do this:

• Alternative 1: Use 1 list to store objects of both classes.

  • Pros: Minimal coding is required as only 1 list is required to store the 2 different class objects.

  • Cons: Whenever we want to perform an operation on an object stored, we need to check its class.

• Alternative 2 (current choice): Use 2 lists to store objects of the 2 classes separately.

  • Pros: When we want to perform an operation on all the objects stored in a list, each object can be treated the same as they are from the same class.

  • Cons: More coding is required to create 2 separate lists.

While both alternatives have advantages and disadvantages, we feel that the second alternative’s advantages outweigh its disadvantages in the long run. It is easier to maintain the 2 separate lists of objects, whereby each list contains objects of the same class, especially as we make the 2 classes more specialized. The inconvenience of creating 2 separate lists will be counterbalanced by the convenience in the long run.

4.5. Logging

We are using java.util.logging package for logging. The LogsCenter class is used to manage the logging levels and logging destinations as follows:

• The logging level can be controlled using the logLevel setting in the configuration file (See Section 4.6, “Configuration”).

• The Logger for a class can be obtained using LogsCenter.getLogger(Class) which will log messages according to the specified logging level.

• Currently log messages are output through: Console and to a .log file.

The following are the four logging levels:

• SEVERE means critical problem was detected which may possibly cause the termination of the application.

• WARNING means application can continue, but with caution.

• INFO shows noteworthy actions by the application.

• FINE gives details that are not usually noteworthy but may be useful in debugging e.g. printing the actual list instead of just its size.

4.6. Configuration

Certain properties of the application (e.g. App name, logging level) can be controlled through the configuration file (default: config.json).

5. Documentation

We use asciidoc for writing documentation.

ℹ️	We choose asciidoc over Markdown because asciidoc, although a bit more complex than Markdown, provides more flexibility in formatting.

5.1. Editing Documentation

See UsingGradle.adoc to learn how to render .adoc files locally to preview the end result of your edits. Alternatively, you can download the AsciiDoc plugin for IntelliJ, which allows you to preview the changes you have made to your .adoc files in real-time.

5.2. Publishing Documentation

See UsingTravis.adoc to learn how to deploy GitHub Pages using Travis.

5.3. Converting Documentation to PDF format

We use Google Chrome for converting documentation to PDF format, as Chrome’s PDF engine preserves hyperlinks used in webpages.

Here are the steps to convert the project documentation files to PDF format:

1. Follow the instructions in UsingGradle.adoc to convert the AsciiDoc files in the docs/ directory to HTML format.

2. Go to your generated HTML files in the build/docs folder, right click on them and select Open with → Google Chrome.

3. Within Chrome, click on the Print option in Chrome’s menu.

4. Set the destination to Save as PDF, then click Save to save a copy of the file in PDF format. For best results, use the settings indicated in the screenshot below.

Figure 30. Saving documentation as PDF files in Chrome

6. Testing Procedures

This sections describes the different ways to do testing on the application.

6.1. Methods for Running Tests

There are three ways to run tests.

💡	The most reliable way to run tests is the 3rd one. The first two methods might fail some GUI tests due to platform/resolution-specific idiosyncrasies.

Method 1: Using IntelliJ JUnit test runner

You can choose to run all tests or only a subset of tests:

• To run all tests, right-click on the src/test/java folder and choose Run 'All Tests'.

• To run a subset of tests, right-click on a test package, test class, or a test and choose Run 'ABC'.

Method 2: Using Gradle

To run tests using gradle, open a console and run the command gradlew clean allTests (Mac/Linux: ./gradlew clean allTests).

ℹ️	See UsingGradle.adoc for more info on how to run tests using Gradle.

Method 3: Using Gradle (headless)

Thanks to the TestFX library we use, our GUI tests can be run in the headless mode. In the headless mode, GUI tests do not show up on the screen. That means the developer can do other things on the Computer while the tests are running.

To run tests in headless mode, open a console and run the command gradlew clean headless allTests (Mac/Linux: ./gradlew clean headless allTests).

6.2. Test Types

We have two types of tests, based on whether the tests involve the GUI:

1. GUI tests which include:

   1. System tests
      These test the entire App by simulating user actions on the GUI. System tests are in the systemtests package.

   2. Unit tests
      These test the individual components. They can be found in seedu.address.ui package.

2. Non-GUI tests which include:

   1. Unit tests
      These target the lowest level methods/classes.
      Example: seedu.adress.commons.StringUtilTest.

   2. Integration tests
      These check the integration of multiple code units which are assumed to be working.
      Example: seedu.address.storage.StorageManagerTest.

   3. Hybrids of unit and integration tests
      These tests check multiple code units as well as how the are connected together.
      Example: seedu.address.logic.LogicManagerTest.

6.3. Troubleshooting Test

The following describes an example of troubleshooting test:

• Problem: HelpWindowTest fails with a NullPointerException.

  • Reason: One of its dependencies, UserGuide.html in src/main/resources/docs is missing.

  • Solution: Execute Gradle task processResources.

7. Dev Ops

This section features softwares which can be used to track the progress of the application development.

7.1. Build Automation

See UsingGradle.adoc to learn how to use Gradle for build automation.

7.2. Continuous Integration

We use Travis CI and AppVeyor to perform Continuous Integration on our projects. See UsingTravis.adoc and UsingAppVeyor.adoc for more details.

7.3. Coverage Reporting

We use Coveralls to track the code coverage of our projects. See UsingCoveralls.adoc for more details.

7.4. Documentation Previews

When a pull request has changes to asciidoc files, you can use Netlify to see a preview of how the HTML version of those asciidoc files will look like when the pull request is merged. See UsingNetlify.adoc for more details.

7.5. Release Creation

Here are the steps to create a new release:

1. Update the version number in MainApp.java.

2. Generate a JAR file using Gradle.

3. Tag the repo with the version number e.g. v0.1.

4. Create a new release using GitHub and upload the JAR file you created.

7.6. Dependencies Management

A project often depends on third-party libraries. For example, this application depends on the Jackson library for XML parsing. Managing these dependencies can be automated using Gradle. For example, Gradle can download the dependencies automatically, which is better than these alternatives:
a. including those libraries in the repo (this bloats the repo size); and
b. requiring developers to download those libraries manually (this creates extra work for developers)

Appendix A: Suggested Programming Tasks to Get Started

Suggested path for new programmers:

1. First, add small local-impact (i.e. the impact of the change does not go beyond the component) enhancements to one component at a time. Some suggestions are given in Section A.1, “Improving each component”.

2. Next, add a feature that touches multiple components to learn how to implement an end-to-end feature across all components. Section A.2, “Creating a new command: remark” explains how to go about adding such a feature.

A.1. Improving each component

Each individual exercise in this section is component-based (i.e. you would not need to modify the other components to get it to work).

Logic component

Scenario: You are in charge of logic. During dog-fooding, your team realize that it is troublesome for the user to type the whole command in order to execute a command. Your team devise some strategies to help cut down the amount of typing necessary, and one of the suggestions was to implement aliases for the command words. Your job is to implement such aliases.

💡	Do take a look at Section 3.3, “Logic Component” before attempting to modify the Logic component.

1. Add a shorthand equivalent alias for each of the individual commands. For example, besides typing clear, the user can also type c to remove all activities in the list.

   • Hints

     • Just like we store each individual command word constant COMMAND_WORD inside *Command.java (e.g. FindCommand#COMMAND_WORD, DeleteCommand#COMMAND_WORD), you need a new constant for aliases as well (e.g. FindCommand#COMMAND_ALIAS).

     • AddressBookParser is responsible for analyzing command words.

   • Solution

     • Modify the switch statement in AddressBookParser#parseCommand(String) such that both the proper command word and alias can be used to execute the same intended command.

     • Add new tests for each of the aliases that you have added.

     • Update the user guide to document the new aliases.

     • See this PR for the full solution.

Model component

Scenario: You are in charge of model. One day, the logic-in-charge approaches you for help. He wants to implement a command such that the user is able to remove a particular tag from everyone in the desk board, but the model API does not support such a functionality at the moment. Your job is to implement an API method, so that your teammate can use your API to implement his command.

💡	Do take a look at Section 3.4, “Model Component” before attempting to modify the Model component.

1. Add a removeTag(Tag) method. The specified tag will be removed from everyone in the desk board.

   • Hints

     • The Model and the AddressBook API need to be updated.

     • Think about how you can use SLAP to design the method. Where should we place the main logic of deleting tags?

     • Find out which of the existing API methods in AddressBook and Person classes can be used to implement the tag removal logic. AddressBook allows you to update a activity, and Person allows you to update the tags.

   • Solution

     • Implement a removeTag(Tag) method in AddressBook. Loop through each activity, and remove the tag from each activity.

     • Add a new API method deleteTag(Tag) in ModelManager. Your ModelManager should call AddressBook#removeTag(Tag).

     • Add new tests for each of the new public methods that you have added.

     • See this PR for the full solution.

       • The current codebase has a flaw in tags management. Tags no longer in use by anyone may still exist on the AddressBook. This may cause some tests to fail. See issue #753 for more information about this flaw.

       • The solution PR has a temporary fix for the flaw mentioned above in its first commit.

Ui component

Scenario: You are in charge of ui. During a beta testing session, your team is observing how the users use your desk board application. You realize that one of the users occasionally tries to delete non-existent tags from a contact, because the tags all look the same visually, and the user got confused. Another user made a typing mistake in his command, but did not realize he had done so because the error message wasn’t prominent enough. A third user keeps scrolling down the list, because he keeps forgetting the index of the last activity in the list. Your job is to implement improvements to the UI to solve all these problems.

💡	Do take a look at Section 3.2, “UI Component” before attempting to modify the UI component.

1. Use different colors for different tags inside activity cards. For example, friends tags can be all in brown, and colleagues tags can be all in yellow.

   Before

   

   After

   

   • Hints

     • The tag labels are created inside the PersonCard constructor (new Label(tag.tagName)). JavaFX’s Label class allows you to modify the style of each Label, such as changing its color.

     • Use the .css attribute -fx-background-color to add a color.

     • You may wish to modify DarkTheme.css to include some pre-defined colors using css, especially if you have experience with web-based css.

   • Solution

     • You can modify the existing test methods for PersonCard 's to include testing the tag’s color as well.

     • See this PR for the full solution.

       • The PR uses the hash code of the tag names to generate a color. This is deliberately designed to ensure consistent colors each time the application runs. You may wish to expand on this design to include additional features, such as allowing users to set their own tag colors, and directly saving the colors to storage, so that tags retain their colors even if the hash code algorithm changes.

2. Modify NewResultAvailableEvent such that ResultDisplay can show a different style on error (currently it shows the same regardless of errors).

   Before

   

   After

   

   • Hints

     • NewResultAvailableEvent is raised by CommandBox which also knows whether the result is a success or failure, and is caught by ResultDisplay which is where we want to change the style to.

     • Refer to CommandBox for an example on how to display an error.

   • Solution

     • Modify NewResultAvailableEvent 's constructor so that users of the event can indicate whether an error has occurred.

     • Modify ResultDisplay#handleNewResultAvailableEvent(NewResultAvailableEvent) to react to this event appropriately.

     • You can write two different kinds of tests to ensure that the functionality works:

       • The unit tests for ResultDisplay can be modified to include verification of the color.

       • The system tests AddressBookSystemTest#assertCommandBoxShowsDefaultStyle() and AddressBookSystemTest#assertCommandBoxShowsErrorStyle() to include verification for ResultDisplay as well.

     • See this PR for the full solution.

       • Do read the commits one at a time if you feel overwhelmed.

3. Modify the StatusBarFooter to show the total number of people in the desk board.

   Before

   

   After

   

   • Hints

     • StatusBarFooter.fxml will need a new StatusBar. Be sure to set the GridPane.columnIndex properly for each StatusBar to avoid misalignment!

     • StatusBarFooter needs to initialize the status bar on application start, and to update it accordingly whenever the desk board is updated.

   • Solution

     • Modify the constructor of StatusBarFooter to take in the number of activities when the application just started.

     • Use StatusBarFooter#handleAddressBookChangedEvent(AddressBookChangedEvent) to update the number of activities whenever there are new changes to the addressbook.

     • For tests, modify StatusBarFooterHandle by adding a state-saving functionality for the total number of people status, just like what we did for save location and sync status.

     • For system tests, modify AddressBookSystemTest to also verify the new total number of activities status bar.

     • See this PR for the full solution.

Storage component

Scenario: You are in charge of storage. For your next project milestone, your team plans to implement a new feature of saving the desk board to the cloud. However, the current implementation of the application constantly saves the desk board after the execution of each command, which is not ideal if the user is working on limited internet connection. Your team decided that the application should instead save the changes to a temporary local backup file first, and only upload to the cloud after the user closes the application. Your job is to implement a backup API for the desk board storage.

💡	Do take a look at Section 3.5, “Storage Component” before attempting to modify the Storage component.

1. Add a new method backupAddressBook(ReadOnlyAddressBook), so that the desk board can be saved in a fixed temporary location.

   • Hint

     • Add the API method in AddressBookStorage interface.

     • Implement the logic in StorageManager and XmlAddressBookStorage class.

   • Solution

     • See this PR for the full solution.

A.2. Creating a new command: remark

By creating this command, you will get a chance to learn how to implement a feature end-to-end, touching all major components of the app.

Scenario: You are a software maintainer for addressbook, as the former developer team has moved on to new projects. The current users of your application have a list of new feature requests that they hope the software will eventually have. The most popular request is to allow adding additional comments/notes about a particular contact, by providing a flexible remark field for each contact, rather than relying on tags alone. After designing the specification for the remark command, you are convinced that this feature is worth implementing. Your job is to implement the remark command.

A.2.1. Description

Edits the remark for a activity specified in the INDEX.
Format: remark INDEX r/[REMARK]

Examples:

• remark 1 r/Likes to drink coffee.
  Edits the remark for the first activity to Likes to drink coffee.

• remark 1 r/
  Removes the remark for the first activity.

A.2.2. Step-by-step Instructions

[Step 1] Logic: Teach the app to accept 'remark' which does nothing

Let’s start by teaching the application how to parse a remark command. We will add the logic of remark later.

Main:

1. Add a RemarkCommand that extends UndoableCommand. Upon execution, it should just throw an Exception.

2. Modify AddressBookParser to accept a RemarkCommand.

Tests:

1. Add RemarkCommandTest that tests that executeUndoableCommand() throws an Exception.

2. Add new test method to AddressBookParserTest, which tests that typing "remark" returns an instance of RemarkCommand.

[Step 2] Logic: Teach the app to accept 'remark' arguments

Let’s teach the application to parse arguments that our remark command will accept. E.g. 1 r/Likes to drink coffee.

Main:

1. Modify RemarkCommand to take in an Index and String and print those two parameters as the error message.

2. Add RemarkCommandParser that knows how to parse two arguments, one index and one with prefix 'r/'.

3. Modify AddressBookParser to use the newly implemented RemarkCommandParser.

Tests:

1. Modify RemarkCommandTest to test the RemarkCommand#equals() method.

2. Add RemarkCommandParserTest that tests different boundary values for RemarkCommandParser.

3. Modify AddressBookParserTest to test that the correct command is generated according to the user input.

[Step 3] Ui: Add a placeholder for remark in PersonCard

Let’s add a placeholder on all our PersonCard s to display a remark for each activity later.

Main:

1. Add a Label with any random text inside PersonListCard.fxml.

2. Add FXML annotation in PersonCard to tie the variable to the actual label.

Tests:

1. Modify PersonCardHandle so that future tests can read the contents of the remark label.

[Step 4] Model: Add Remark class

We have to properly encapsulate the remark in our Person class. Instead of just using a String, let’s follow the conventional class structure that the codebase already uses by adding a Remark class.

Main:

1. Add Remark to model component (you can copy from Address, remove the regex and change the names accordingly).

2. Modify RemarkCommand to now take in a Remark instead of a String.

Tests:

1. Add test for Remark, to test the Remark#equals() method.

[Step 5] Model: Modify Person to support a Remark field

Now we have the Remark class, we need to actually use it inside Person.

Main:

1. Add getRemark() in Person.

2. You may assume that the user will not be able to use the add and edit commands to modify the remarks field (i.e. the activity will be created without a remark).

3. Modify SampleDataUtil to add remarks for the sample data (delete your deskBoard.xml so that the application will load the sample data when you launch it.)

[Step 6] Storage: Add Remark field to XmlAdaptedPerson class

We now have Remark s for Person s, but they will be gone when we exit the application. Let’s modify XmlAdaptedPerson to include a Remark field so that it will be saved.

Main:

1. Add a new Xml field for Remark.

Tests:

1. Fix invalidAndValidPersonAddressBook.xml, typicalPersonsAddressBook.xml, validAddressBook.xml etc., such that the XML tests will not fail due to a missing <remark> element.

[Step 6b] Test: Add withRemark() for PersonBuilder

Since Person can now have a Remark, we should add a helper method to PersonBuilder, so that users are able to create remarks when building a Person.

Tests:

1. Add a new method withRemark() for PersonBuilder. This method will create a new Remark for the activity that it is currently building.

2. Try and use the method on any sample Person in TypicalPersons.

[Step 7] Ui: Connect Remark field to PersonCard

Our remark label in PersonCard is still a placeholder. Let’s bring it to life by binding it with the actual remark field.

Main:

1. Modify PersonCard's constructor to bind the Remark field to the Person 's remark.

Tests:

1. Modify GuiTestAssert#assertCardDisplaysTask(…​) so that it will compare the now-functioning remark label.

[Step 8] Logic: Implement RemarkCommand#execute() logic

We now have everything set up…​ but we still can’t modify the remarks. Let’s finish it up by adding in actual logic for our remark command.

Main:

1. Replace the logic in RemarkCommand#execute() (that currently just throws an Exception), with the actual logic to modify the remarks of a activity.

Tests:

1. Update RemarkCommandTest to test that the execute() logic works.

A.2.3. Full Solution

See this PR for the step-by-step solution.

Appendix B: Product Scope

Target user: University Computing students

Target user profile: Our target users are expected to have the following characteristics:

• have a need to manage a significant number of tasks and events

• prefer desktop apps over other types

• can type fast

• prefer typing over mouse input

• are reasonably comfortable using Linux-style commands and CLI apps

Value proposition: The user will have all their tasks and events in one app. This creates convenience for the user. The CLI also makes it faster than a typical mouse/GUI-driven app

B.1. Feature contribution

The following section describes the major and minor enhancements that each of our members contributes to the development of our product.

B.1.1. Jarrett

Major enhancement: Creating 'overdue' command. This command shows a list of overdue tasks.

Minor enhancement: Creating 'task' and 'event' commands which add Task and Event objects respectively.

B.1.2. Jasmund

Major enhancement: Modifying the GUI to fit our task/event manager application. This includes but is not limited to allowing the UI to display 2 panes for showing the Task and Event lists separately.

Minor enhancement: Modifying the 'help' command. In our application, 'help' can be followed by a command word (e.g. 'help task') so that instructions for only the command desired are shown. Moreover, 'man' command — an alias for 'help' — is also added for users who are familiar with Linux commands.

B.1.3. Karen

Major enhancement: Modifying the Storage component to allow storage of Tasks and Events in an xml file.

Minor enhancement: Creating 'ls' command. This command shows the Event and Task objects added to the Desk Board in 2 separate lists.

B.1.4. Yuan Quan

Major enhancement: Modifying the Model component. This includes creation of Event and Task classes, as well as their superclass, Activity. Other classes relevant to tasks and events are also created, such as DateTime.

Minor enhancement: Creating 'complete' command. This command marks a Task object as completed.

Appendix C: User Stories

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

Priority	As a …​	I want to …​	So that I can…​
* * *	new user	see usage instructions	figure out how to use the application
* * *	student	add a new task	record a new task to remind myself
* * *	student	add a new event	record a new event to remind myself
* * *	student	add the location of an event	be in the right location
* * *	student	add items to bring for an event	attend an event with all the required items
* * *	student	view upcoming tasks (in order of earliest to latest)	manage my time and finish my tasks on time
* * *	student	view upcoming events (in order of earliest to latest)	attend my events
* * *	student	view free time slots	arrange for other events
* * *	student	change the deadline of a task	adjust my schedule when a deadline changes
* * *	student	change the time of an event	see the updated schedule in case there are changes
* * *	student	change the location of an event	be in the right location when the location changes
* * *	student	delete a task	remove tasks I no longer need to complete
* * *	student	delete an event	remove events I no longer need to attend
* * *	student	find a task by name	locate details of a task without having to go through the entire list
* * *	student	find an event by name	locate details of an event without having to go through the entire list
* * *	student	mark a task as complete	tell which tasks are completed and which are not
* * *	student	view completed tasks	be assured I have completed a task
* * *	student	import entries from another file	easily add entries previously saved in another file
* * *	forgetful student	view overdue tasks	be assured I did not miss any deadline
* * *	forgetful student	get notification for upcoming tasks	never forget to complete my tasks
* * *	forgetful student	get notification for upcoming events	never forget to attend my events
* *	busy student	sort tasks based on priority	allocate sufficient time for each task
* *	busy student	filter tasks based on time period	view only tasks with deadlines within a certain time period
* *	busy student	filter events based on time period	view only events within a certain time period
* *	busy student	filter tasks based on tags	view only certain tasks when there are too many tasks to view
* *	busy student	filter events based on tags	view only certain events when there are too many events to view
* *	procrastinating student	add estimated time needed to complete a task	estimate when to start on a task to complete it on time
* *	procrastinating student	view contact details of person in-charge for a deadline extension	have enough time to complete my assignments despite my tight schedule
* *	busy student	view free time slots before a deadline	know how much time I have when I’m actually free to finish my tasks
* *	student	view common free time slots among my group mates	arrange a group meeting
* *	organised student	add multiple deadlines for a task	keep track of project progress
* *	NUS student	import timetable from NUSMods	avoid the trouble of keying in my lecture and tutorial schedules manually
*	student	be rewarded for completing a task	feel a sense of achievement
*	student	hide private events	minimize chance of someone else seeing them by accident [appendix] == Use Cases (For all use cases below, the System is the CLIndar and the Actor is the User, unless specified otherwise) [discrete] === Use case: Add task MSS 1. User adds a task into CLIndar by typing a command 2. CLIndar parses command typed and adds in the task + Use case ends. Extensions [none] 2a. CLIndar detects that the format of the command typed is invalid + [none] 3a1. CLIndar shows an error message + Use case ends. === Use case: Add events MSS 1. User adds an event into CLIndar by typing a command 2. CLIndar parses command typed and adds in the event + Use case ends. Extensions [none] 3a. CLIndar detects that the format of the command typed is invalid + [none] 3a1. CLIndar shows an error message + Use case ends. === Use case: Complete task MSS 1. User requests to mark a task as completed by typing a command 2. CLIndar shows a list of uncompleted tasks 3. User selects the task to be marked as completed by the index 4. CLIndar marks the selected task as completed + Use case ends. Extensions [none] * 2a. The list is empty + Use case ends. * 3a. The given index is invalid. + [none] 3a1. CLIndar shows an error message + Use case resumes at step 2. === Use case: Show urgent task MSS 1. User requests to show all tasks before a certain date by typing a command 2. CLIndar shows a list of uncompleted tasks with deadline before the provided date + Use case ends. Extensions [none] * 1a. The given date is invalid + [none] 1a1. CLIndar shows an error message + Use case resumes at step 1. * 2a. The list is empty. + Use case ends. === Use case: Show help for command MSS 1. User requests to show help for command requested 2. CLIndar shows the help message for the requested command + Use case ends. Extensions [none] * 1a. The command requested is invalid + [none] * 1a1. CLIndar shows an error message + Use case resumes at step 1. Use case ends. {More to be added} [appendix] == Non Functional Requirements . Should work on any mainstream OS as long as it has Java 1.8.0_60 or higher installed. . Should be able to hold up to 500 tasks and 500 events without a noticeable sluggishness in performance for typical usage. . 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. . The system should respond within two seconds when the user enters a command. . The system CLI commands should be easy to remember for the average English speaker. . A novice user should be able to understand how to use the system in a short period of time. . The notification feature should not be deemed too annoying for the user. {More to be added} [appendix] == Glossary Tasks:: A particular work assigned by a professor. Completed:: A task or event that has finished. Deadline:: The date and time by which an event will happen or a task is due. Duration:: The amount of time left to complete a task or prepare for an event. Events:: A thing that will occur in a certain place at a particular interval of time. Location:: The place where the event will occur. Mainstream OS:: Windows, Linux, Unix, OS-X Private contact detail:: A contact detail that is not meant to be shared with others. Overdue:: A task that has not been completed past the deadline. Things to bring:: Things to be brought for an event that is going to happen. Urgent:: A task due or event that will happen within the next 24 hours. [appendix] == Product Survey *Product Name Author: …​ Pros: * …​ * …​ Cons: * …​ * …​ [appendix] == Instructions for Manual Testing Given below are instructions to test the app manually. [NOTE] These instructions only provide a starting point for testers to work on; testers are expected to do more exploratory testing. === Launch and Shutdown . Initial launch .. Download the jar file and copy into an empty folder .. Double-click the jar file Expected: Shows the GUI with a set of sample contacts. The window size may not be optimum. . Saving window preferences .. Resize the window to an optimum size. Move the window to a different location. Close the window. .. Re-launch the app by double-clicking the jar file. Expected: The most recent window size and location is retained. { more test cases …​ } === Deleting a activity . Deleting a activity while all activities are listed .. Prerequisites: List all activities using the list command. Multiple activities in the list. .. 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. .. Test case: delete 0 Expected: No activity is deleted. Error details shown in the status message. Status bar remains the same. .. Other incorrect delete commands to try: delete, delete x (where x is larger than the list size) {give more} Expected: Similar to previous. { more test cases …​ } === Saving data . Dealing with missing/corrupted data files .. {explain how to simulate a missing/corrupted file and the expected behavior} { more test cases …​ }