DeveloperGuide.adoc

ePiggy - Developer Guide

By: Team A+ for 2103T      Since: Feb 2019      Last Updated: April 2019      Licence: MIT

1. Introduction

Welcome to ePiggy! ePiggy is a desktop application designed to inculcate good spending habits in students through allowing them to track their finances. It includes everything from tracking expenses, managing budgets to setting goals.

This developer guide is a self-contained resource designed to align potential developers to a common vision. It guides developers of all levels, allowing them to learn more about the behind the scenes workings and how to make use of them effectively.

If you want to learn how you can make ePiggy even better, start here!

Callouts

Callouts are boxes with icons to point out some information. These are the 3 callouts used throughout this developer guide:

ℹ️	This represents a note. A note indicates important, additional information. Be sure to read these notes as they might be applicable to you!

💡	This represents a tip. A tip denotes something that is often handy, and good for you to know. Tips are often less crucial, and you can choose to skip them.

⚠️	This represents a warning. A warning denotes something of crucial importance, and you should be extremely cautious when reading the statement.

In this Developer Guide:

• 1. Introduction
• 2. Setting up
  • 2.1. Prerequisites
  • 2.2. Setting up the project in your computer
  • 2.3. Verifying the setup
  • 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. Common classes
• 4. Implementation
  • 4.1. Add budget feature
  • 4.2. Edit budget feature
  • 4.3. Delete budget feature
  • 4.4. Find Expense feature
  • 4.5. Set Goal feature
  • 4.6. View Goal feature
  • 4.7. Undo/Redo feature
  • 4.8. Report feature
  • 4.9. autocomplete feature
  • 4.10. [Proposed] Data Encryption
  • 4.11. Logging
  • 4.12. Configuration
• 5. Documentation
  • 5.1. Editing Documentation
  • 5.2. Publishing Documentation
  • 5.3. Converting Documentation to PDF format
  • 5.4. Site-wide Documentation Settings
  • 5.5. Per-file Documentation Settings
  • 5.6. Site Template
• 6. Testing
  • 6.1. Running Tests
  • 6.2. Types of tests
  • 6.3. Troubleshooting Testing
• 7. Dev Ops
  • 7.1. Build Automation
  • 7.2. Continuous Integration
  • 7.3. Coverage Reporting
  • 7.4. Documentation Previews
  • 7.5. Making a Release
  • 7.6. Managing Dependencies
• Appendix A: Suggested Programming Tasks to Get Started
  • A.1. Improving each component
  • A.2. Creating a new command: remark
• Appendix B: Product Scope
• Appendix C: User Stories
• Appendix D: Use Cases
• Appendix E: Non Functional Requirements
• Appendix F: Glossary
• Appendix G: Product Survey
• Appendix H: Instructions for Manual Testing
  • H.1. Launch and Shutdown
  • H.2. Deleting an expense
  • H.3. Saving data

2. Setting up

2.1. Prerequisites

1. JDK 9 or later

   ⚠️	JDK 10 on Windows will fail to run tests in headless mode due to a JavaFX bug. Windows developers are highly recommended to use JDK 9.

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. Setting up the project in your computer

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

2. Open IntelliJ (if you are not in the welcome screen, click File > Close Project to close the existing project dialog first)

3. Set up the correct JDK version for Gradle

   1. Click Configure > Project Defaults > Project Structure

   2. Click New…​ and find the directory of the JDK

4. Click Import Project

5. Locate the build.gradle file and select it. Click OK

6. Click Open as Project

7. Click OK to accept the default settings

8. Open a console 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.

9. Open MainWindow.java and check for any code errors

   1. Due to an ongoing issue with some of the newer versions of IntelliJ, code errors may be detected even if the project can be built and run successfully

   2. To resolve this, place your cursor over any of the code section highlighted in red. Press ALT+ENTER, and select Add '--add-modules=…​' to module compiler options for each error

10. Repeat this for the test folder as well (e.g. check HelpWindowTest.java for code errors, and if so, resolve it the same way)

2.3. Verifying the setup

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

2. Run the tests to ensure they all pass.

2.4. Configurations to do before writing code

2.4.1. Configuring the coding style

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,

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

2. Select Editor > Code Style > Java

3. Click on the Imports tab to set the order

   • 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: The order is import static all other imports, import java.*, import javax.*, import org.*, import com.*, import all other imports. Add a <blank line> between each import

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

2.4.2. Updating documentation to match your fork

After forking the repo, the documentation will still have the SE-EDU branding and refer to the se-edu/addressbook-level4 repo.

If you plan to develop this fork as a separate product (i.e. instead of contributing to se-edu/addressbook-level4), you should do the following:

1. Configure the site-wide documentation settings in build.gradle, such as the site-name, to suit your own project.

2. Replace the URL in the attribute repoURL in DeveloperGuide.adoc and UserGuide.adoc with the URL of your fork.

2.4.3. Setting up CI

Set up Travis 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. Getting started with coding

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

3.1. Architecture

Figure 1. Architecture Diagram

The Architecture Diagram given above explains the high-level design of the App. 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: Initializes the components in the correct sequence, and connects them up with each other.

• At shut down: Shuts down the components and invokes cleanup method where necessary.

Commons represents a collection of classes used by multiple other components. The following class plays an important role at the architecture level:

• LogsCenter : Used by many classes to write log messages to the App’s log file.

The rest of the App consists of 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.

Each of the four components

• Defines its API in an interface with the same name as the Component.

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

For example, the Logic component (see the class diagram given below) defines it’s API in the Logic.java interface and exposes its functionality using the LogicManager.java class.

Figure 2. Class Diagram of the Logic Component

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 deleteExpense 1.

Figure 3. Component interactions for deleteExpense 1 command

The sections below give more details of each component.

3.2. UI component

Figure 4. Structure of the UI Component

API : Ui.java

The UI consists of a MainWindow that is made up of parts e.g.CommandBox, ResultDisplay, PersonListPanel, 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.

• Listens for changes to Model data so that the UI can be updated with the modified data.

3.3. Logic component

Figure 5. Structure of the Logic Component

API : Logic.java

1. Logic uses the EPiggyParser class to parse the user command.

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

3. The command execution can affect the Model (e.g. adding a expense).

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

5. In addition, the CommandResult object can also instruct the Ui to perform certain actions, such as displaying help to the user.

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

Figure 6. Interactions Inside the Logic Component for the deleteExpense 1 Command

3.4. Model component

Figure 7. Structure of the Model Component

API : Model.java

The Model,

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

• stores the ePiggy data.

• exposes an unmodifiable ObservableList<Expense> 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.

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

ℹ️	As a more OOP model, we can store a Tag list in ePiggy, which Expense can reference. This would allow ePiggy to only require one Tag object per unique Tag, instead of each Expense needing their own Tag object. An example of how such a model may look like is given below.

3.5. Storage component

Figure 8. Structure of the Storage Component

API : Storage.java

The Storage component,

• can save UserPref objects in json format and read it back.

• can save the ePiggy data in json format and read it back.

3.6. Common classes

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

4. Implementation

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

4.1. Add budget feature

This command allows users to add a new budget to monitor their expenses within a user-input period of time.
.This command requires users to specify the amount, start date and time period (in days) of the budget in the command.

• addBudget $/500 p/31 d/01/03/2019
  

The above command adds a budget with $500 which starts on 1st March 2019 and lasts for 31 days.

The budget will compute the end date and provide a status based on the local date. The status will include whether the budget is an old, current or future budget, as well as the remaining amount until the budget is exceeded and remaining days till the end of the budget. This is so that users are aware about how much they have spent.

Adding of overlapping budgets are not allowed in ePiggy.

ℹ️	A budget is considered overlapping if any of the dates in between (inclusive) one budget’s start and end dates is the same as the dates in between (inclusive) another budget’s start and end dates.

4.1.1. Current Implementation

Given below is a sequence diagram of how the addBudget command works:

Figure: Add Budget Command Sequence Diagram

The command is first parsed into AddBudgetCommandParser, which separates the arguments into their respective fields. A new Budget is created and parsed into AddBudgetCommand.
As long as the Budget object created does not overlap with any existing Budget objects, the Budget will be added with Model#addBudget() and saved into the ePiggy storage.

Example usage scenario:
1. User launches application and enters addBudget $/500 p/31 d/01/03/2019.
2. AddBudgetCommandParser takes in the arguments and parses the command to create the appropriate Budget.
3. The AddBudgetCommand is passed back to the LogicManager, and the method execute() is called. The Budget is then added to the model.

4.1.2. Design Considerations

Aspect: What user input should addBudget require?

• Alternative 1 (current choice): the addBudget command requires the amount, start date and time period (in days) of the budget.

  • Pros: Easy to make recurring daily, weekly or annual budgets.

  • Cons: If users have the start date and end date in mind, they will have to manually calculate the period between the dates and input that instead of the end date.

• Alternative 2 : the addBudget command requires the amount, start date and end date of the budget.

  • Pros: Easy to make recurring monthly budgets.

  • Cons: Could cause users to miss out on certain dates if they want budgets that are recurring (eg. sets a budget from 1st March to 30th March and 1st April to 30th April – 31st March is missed out).

4.2. Edit budget feature

ePiggy allows the user to edit the current budget, with any of the specified parameters in addBudget.

• editBudget $/300

• editBudget $/400 p/7

The above commands edit the current budget to $300 and $400 with a period of 7 days respectively.
Similarly to the addBudget command, budgets’ dates should not overlap each other. Hence, the budget cannot be edited such that the edited budget overlaps with another budget.

ℹ️	A budget is considered overlapping if any of the dates in between (inclusive) one budget’s start and end dates is the same as the dates in between (inclusive) another budget’s start and end dates.

💡	If the current budget is edited until it is no longer a current budget, it can no longer be edited. Instead, simply add a new current budget using the addBudget command.

4.2.1. Current Implementation

The command’s current implementation uses part of the legacy implementation to update the budget. The arguments are first parsed into EditBudgetCommandParser, which separates the arguments into their respective fields.
An EditBudgetDescriptor object is then created to temporarily hold this new information.

ℹ️	The prefixes applicable to editBudget are $/, p/ and d/. At least one of them must follow the editBudget command word.

Afterwards, a budget object is created from the EditBudgetDescriptor object. Then, the budget object is passed into ePiggy through Model.#setCurrentBudget(), which will replace the current budget with the new budget passed in.
Since only the current budget can be edited, the editBudget command will first check if a current budget is present in ePiggy’s budgetList through Model#getCurrentBudgetIndex(). If the current budget does not exist, the command will feedback to the user that the command entered is invalid.

4.2.2. Design Considerations

Aspect: Should we use a boolean hasCurrentBudget method or use the index of the current budget to verify if a current budget exists?

• Alternative 1 (current choice):
  The index of the current budget is returned to the editBudgetCommand. If the returned integer is -1, it means that there is no current budget present. The index is then used to retrieve the current budget.

  • Pros: No additional method implementations required. The methods Model#getFilteredBudgetList().get() are sufficient to get the current budget.

  • Cons: Calculations are done in the editBudget command’s execute method.

• Alternative 2:
  Using a boolean hasCurrentBudget method to check if a current budget exists in budgetList, then another getCurrentBudget method to get the current budget.

  • Pros: Code will be written in ePiggy rather than at editBudget command and can be easily used for other commands.

  • Cons: Will need to implement additional methods. Reduces the abstraction has the current budget is exposed to the entire project as it is a public method.

After much consideration, we decided to choose option 1 as other commands should not need to access the current budget specifically. Hence, it will be better to have a greater level of abstraction.

4.3. Delete budget feature

ePiggy allows the user to delete any budget, using the displayed index of the specific budget.

• deleteBudget 2

The above command deletes the Budget with the displayed index of #2.
The Budget to be deleted is identified by its displayed index and subsequently deleted.

4.3.1. Current Implementation

Given below is a sequence diagram of how the deleteBudget command works:

Figure: Delete Budget Command Sequence Diagram

The command’s current implementation retrieves the budgetList from ePiggy and removes the budget at the zero-based version of the displayed index.
A listener has been added to budgetList, so the order in which the budgets are displayed is the same as the order of the budgets in budgetList. Furthermore, the indexes are unique.
Hence, if the index input by the user is negative or greater than the size of budgetList, this would indicate that the budget specified does not exist. The user will receive a feedback that the index specified is invalid.

4.4. Find Expense feature

ePiggy allows the user to filter specific expenses by entering multiple keywords. Expenses that satisfy all the keywords are displayed in the expense list panel.

• findExpense n/Nasi Lemak $/4.00 d/2019/04/01 t/lunch

The above command finds expense(s) with the Name Nasi Lemak, Cost of $4.00, purchased on Date 1st April, 2019 and tagged with Tag lunch.

ℹ️	Date format is YYYY/MM/DD.

💡	All keywords in this command are optional, provided that there is at least one input keyword. For example, suppose we wabt to filter out all Expense s with Cost between $1 and $10.5 (both inclusive), then the command should be just findExpense $/1:10.5. Similarly for other type of keywords.

4.4.1. Current Implementation

Given below is a UML sequence diagram of how the findExpense command works along with a step-by-step explanation.

Figure: FindExpenseCommand UML Sequence Diagram

Step 1: User enters findExpense n/Nasi Lemak $/4.00 d/2019/04/01 t/lunch. The command is received by EPiggyParser which then creates FindExpenseCommandParser object and and calls FindExpenseCommandParser#parse() method.

Step 2: FindExpenseCommandParser#parse() first checks if input is invalid and throws a ParseException otherwise it calls ArgumentTokenizer#tokenize() to tokenize the String input into keywords and store them in an ArgumentMultimap Object.

Step 3: FindExpenseCommandParser#parse() method then creates an ExpenseContainsKeywordsPredicate Object. It implements Predicate<Expense> interface. It performs the filtering of expenses.

Step 4: A FindExpenseCommand object is created with ExpenseContainsKeywordsPredicate as parameter and returned to LogicManager.

Step 5: LogicManager calls FindCommand#execute(),which then calls Model#updateFilteredExpenseList() method to update the predicate of FilteredList<Expense>. FilteredList now contains only a set of expenses which was filtered by the new predicate.

Step 6: Expense List panel is updated by filtered set of expenses. A CommandResult is then created and returned to LogicManager.

4.5. Set Goal feature

This command allows users to set a savings goal that they would like to save up to.
It requires the user to specify the name of the goal, as well as the amount they would like to hit.

• setGoal n/Nintendo Switch $/499

The command above sets a goal with the name Nintendo Switch and with the amount $499

4.5.1. Current Implementation

Given below is a sequence diagram of how the setGoal command works:

Figure: SetGoalCommand Sequence Diagram.

The command is first parsed into SetGoalCommandParser, which separates the arguments into their respective fields. A new Goal is created and parsed into SetGoalCommand. Goal will then be set with Model#setGoal() and saved into the ePiggy Storage.

Example usage scenario:
1. User launches application and enters setGoal n/Nintendo Switch $/499.
2. SetGoalCommandParser takes in the arguments and parses the command to create the appropriate Goal.
3. The SetGoalCommand is passed back to the LogicManager, and the method execute() is called. Goal is then set to the model.

4.5.2. Design considerations

Aspect: setGoal (1 goal) VS addGoal (multiple goals)

• Alternative 1 (current choice): setGoal (1 goal)
  

  • Pros: Easier to implement. Makes ePiggy easier to use.

  • Cons: Limits the user experience by allowing only 1 savings goal.

• Alternative 2: addGoal (multiple goals)

  • Pros: Gives user freedom to set more than 1 goal.

  • Cons: Makes ePiggy more complicated, not suitable for younger age groups.

4.6. View Goal feature

This command allows users to view their goal set, as well as to check how much more the user has to save in order to reach the goal.

• viewGoal

Based on the amount of savings the user has, the command will output 2 different types of messages.

Firstly, the command will first output the current goal that the user has set.

Next, if the user has not reached the goal amount (savings less than goal), it will output the difference of the savings and the goal, indicating how much more the user has to save to reach the goal.
However, if the user has reached the goal amount (savings greater than goal), it will output a message congratulating the user for reaching their goal.

4.6.1. Current Implementation

The command will first obtain the current savings and current goal from the model that the user has set.
Taking goal minus savings, the result is stored in a temporary float diff.
If diff is positive, diff is passed to CommandResult, and the amount is displayed to show the user how much more they have to save. If diff is negative, the congratulation message is passed to CommandResult.

ℹ️	If a goal has not been set by the user, the command will use a default goal which has an empty name and $0 for the amount.

4.7. Undo/Redo feature

4.7.1. Current Implementation

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

• VersionedEPiggy#commit() — Saves the current ePiggy state in its history.

• VersionedEPiggy#undo() — Restores the previous ePiggy state from its history.

• VersionedEPiggy#redo() — Restores a previously undone ePiggy state from its history.

These operations are exposed in the Model interface as Model#commitEPiggy(), Model#undoEPiggy() and Model#redoEPiggy() 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 VersionedEPiggy will be initialized with the initial ePiggy state, and the currentStatePointer pointing to that single ePiggy state.

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

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

ℹ️	If a command fails its execution, it will not call Model#commitEPiggy(), so the ePiggy state will not be saved into the addressBookStateList.

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

ℹ️	If the currentStatePointer is at index 0, pointing to the initial ePiggy state, then there are no previous ePiggy states to restore. The undo command uses Model#canUndoEPiggy() to check if this is the case. If so, it will return an error to the user rather than attempting to perform the undo.

The following sequence diagram shows how the undo operation works:

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

ℹ️

If the currentStatePointer is at index addressBookStateList.size() - 1, pointing to the latest ePiggy state, then there are no undone ePiggy states to restore. The redo command uses Model#canRedoEPiggy() to check if this is the case. If so, it will return an error to the user rather than attempting to perform the redo.

Step 5. The user then decides to execute the command list. Commands that do not modify the ePiggy, such as list, will usually not call Model#commitEPiggy(), Model#undoEPiggy() or Model#redoEPiggy(). Thus, the addressBookStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitEPiggy(). Since the currentStatePointer is not pointing at the end of the addressBookStateList, all ePiggy states after the currentStatePointer will be purged. We designed it this way because 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:

4.7.2. Design Considerations

Aspect: How undo & redo executes

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

  • 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 deleteExpense, just save the expense being deleted).

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

Aspect: Data structure to support the undo/redo commands

• Alternative 1 (current choice): Use a list to store the history of ePiggy states.

  • Pros: 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 VersionedEPiggy.

• Alternative 2: Use HistoryManager for undo/redo

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

  • Cons: Requires dealing with commands that have already been undone: We must remember to skip these commands. Violates Single Responsibility Principle and Separation of Concerns as HistoryManager now needs to do two different things.

4.8. Report feature

This command allows users to view the report within a user-input period of time.

Given below is a sequence diagram of how the report command works:

Figure: Report Command Sequence Diagram

This command requires users to specify the date, month or year of the report in the command.

• report d/DD/MM/YYYY
  

The above command shows a report on specified date.

• report d/MM/YYYY
  

The above command shows a report on specified month.

• report d/YYYY
  

The above command shows a report on specified year.

• report
  

The above command shows a completed report from first day of user launches the ePiggy.

Commands with different format of tag d/ will generate a report with different charts.

Eg: report d/21/03/2019

The above report command will generate a report of 21 Mar 2019 with AreaChart.

ℹ️	Only last tag d/ is used to generate a report if multiply of d/ appear.

4.8.1. Current Implementation

The command is first parsed into ReportCommandParser, which separates the arguments into their respective fields. A new localDate object is created and type of the report are generated according to the date format of d/. The model, localDate and type are parsed into ReportCommand.

The reportCommand will initialize ReportWindow and the method displayReportController of the object ReportWindow will be invoked.

The displayReportController method will select a specified type of report to display the report.

Example usage scenario:
1. User launches application and enters Report d/21/03/2019.
2. ReportCommandParser takes in the arguments and parses the command to create the appropriate localDate.
3. The ReportWindow is passed back to the LogicManager, and the method execute() is called. The ReportWindow is initialized.
4. The method displayReportController is called and report will show.

4.8.2. Design Considerations

Aspect: How to make report more readable?

• Alternative 1 (current choice): the report command uses a chart to display different data of expenses, budgets and allowances.

  • Pros: Easy to know how much a user have spend on that date, that month or that year. Easy to compare with previous month or year.

  • Cons: The details of the expenses, budgets and allowances cannot show in the chart.

• Alternative 2 : Show the records of expenses, budgets and allowances in details line by line.

  • Pros: User can know the details of each records.

  • Cons: Report feature becomes extra because list command can do the same thing.

4.9. autocomplete feature

This feature allows users to reduce the typing time and learning cost of using ePiggy. Any command line application without an autocomplete feature is a nightmare for the user. The users not only need to type all the existing commands correctly but also need to remember many different parameters in each commands. EPiggy tries to be user friendly. Autocomplete feature helps the users overcome these problems.

Given below is an activity diagram of how the autocomplete feature works:

Figure: Autocomplete activity Diagram

This feature first requires users to enter a few letters on the commandBox of ePiggy, and then press Tab key on the keyboard to autocomplete the command. If the completed command is not what you want, delete the command. Enter the same letters, and press Tab again. Another command will show if the letters match another command.

Example: enter letter 'a' and then press Tab, the command "addExpense n/ $/ t/ d/ " will show. Delete the command, enter 'a' again and press Tab, the addBudget or addAllowance command will show.

ℹ️	The autocomplete feature compares the last part of sub string from user input to the prefix of command in the checklist. It is non-case sensitive.

Example: user types " hello add " to the commandBox, the sub string is "add". "add" is used to compare with commands in the checklist such as "setBudget", "addExpense", "addAllowance". Two commands "addExpense" and "addAllowance" will return but only one of them will replace "add" in the commandBox. The commandBox will show " hello addExpense n/ $/ t/ d/ " or " hello addAllowance n/ $/ d/ ".

4.9.1. Current Implementation

The code of the autocomplete function is in CommandBox class. The autoCompleteText method is invoked when user presses Tab. The sub-string (last part split by white space) of user input text and a checklist of commands pass into findString(). findString() returns an array of matched commands. One element in the array replaces and shows in the commandBox.

Example usage scenario:
1. User launches application and enters addE.
2. autoCompleteText() is invoked.
2. findString() takes in the arguments and returns an array of matched commands.
3. findString() forms a new string using user input. One element in return array is appended at the end of the new string. This new string replaces and shows in the commandBox.

4.9.2. Design Considerations

Aspect: How to implement such function in UI?

• Alternative 1 (current choice): There is not dropdown list appears when user enters letters in commandBox. The matched command shows after user press Tab.

  • Pros: Easy to implement. No third party library is used means that all behaviours of this feature is under control and no extra learning cost is needed.

  • Cons: The auto-completed command is not what the user wants something. User needs to delete the command and invokes the function again.

• Alternative 2: A dropdown list shows when user is typing letters.

  • Pros: User can see any matched commands and select one of them.

  • Cons: Third party library is needed. There is not such kind of library under MIT licence and school is not allow to use them.

4.10. [Proposed] Data Encryption

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

4.11. Logging

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

• The logging level can be controlled using the logLevel setting in the configuration file (See Section 4.12, “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.

Logging Levels

• SEVERE : Critical problem detected which may possibly cause the termination of the application

• WARNING : Can continue, but with caution

• INFO : Information showing the noteworthy actions by the App

• FINE : Details that is not usually noteworthy but may be useful in debugging e.g. print the actual list instead of just its size

4.12. Configuration

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

5. Documentation

We use asciidoc for writing documentation.

ℹ️	We chose 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 9. Saving documentation as PDF files in Chrome

5.4. Site-wide Documentation Settings

The build.gradle file specifies some project-specific asciidoc attributes which affects how all documentation files within this project are rendered.

💡	Attributes left unset in the build.gradle file will use their default value, if any.

Table 1. List of site-wide attributes

Attribute name	Description	Default value
site-name	The name of the website. If set, the name will be displayed near the top of the page.	not set
site-githuburl	URL to the site’s repository on GitHub. Setting this will add a "View on GitHub" link in the navigation bar.	not set
site-seedu	Define this attribute if the project is an official SE-EDU project. This will render the SE-EDU navigation bar at the top of the page, and add some SE-EDU-specific navigation items.	not set

5.5. Per-file Documentation Settings

Each .adoc file may also specify some file-specific asciidoc attributes which affects how the file is rendered.

Asciidoctor’s built-in attributes may be specified and used as well.

💡	Attributes left unset in .adoc files will use their default value, if any.

Table 2. List of per-file attributes, excluding Asciidoctor’s built-in attributes

Attribute name	Description	Default value
site-section	Site section that the document belongs to. This will cause the associated item in the navigation bar to be highlighted. One of: UserGuide, DeveloperGuide, LearningOutcomes*, AboutUs, ContactUs * Official SE-EDU projects only	not set
no-site-header	Set this attribute to remove the site navigation bar.	not set

5.6. Site Template

The files in docs/stylesheets are the CSS stylesheets of the site. You can modify them to change some properties of the site’s design.

The files in docs/templates controls the rendering of .adoc files into HTML5. These template files are written in a mixture of Ruby and Slim.

⚠️

Modifying the template files in docs/templates requires some knowledge and experience with Ruby and Asciidoctor’s API. You should only modify them if you need greater control over the site’s layout than what stylesheets can provide. The SE-EDU team does not provide support for modified template files.

6. Testing

6.1. 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

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

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

Method 2: 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. Types of tests

We have two types of tests:

1. GUI Tests - These are tests involving the GUI. They include,

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

   2. Unit tests that test the individual components. These are in seedu.address.ui package.

2. Non-GUI Tests - These are tests not involving the GUI. They include,

   1. Unit tests targeting the lowest level methods/classes.
      e.g. seedu.address.commons.StringUtilTest

   2. Integration tests that are checking the integration of multiple code units (those code units are assumed to be working).
      e.g. seedu.address.storage.StorageManagerTest

   3. Hybrids of unit and integration tests. These test are checking multiple code units as well as how the are connected together.
      e.g. seedu.address.logic.LogicManagerTest

6.3. Troubleshooting Testing

Problem: HelpWindowTest fails with a NullPointerException.

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

• Solution: Execute Gradle task processResources.

7. Dev Ops

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. Making a Release

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. Managing Dependencies

A project often depends on third-party libraries. For example, ePiggy depends on the Jackson library for JSON parsing. Managing these dependencies can be automated using Gradle. For example, Gradle can download the dependencies automatically, which is better than these alternatives:

1. Include those libraries in the repo (this bloats the repo size)

2. Require 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 expenses 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).

     • EPiggyParser is responsible for analyzing command words.

   • Solution

     • Modify the switch statement in EPiggyParser#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 ePiggy, 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 ePiggy.

   • Hints

     • The Model and the ePiggy 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 ePiggy and Expense classes can be used to implement the tag removal logic. ePiggy allows you to update a expense, and Expense allows you to update the tags.

   • Solution

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

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

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

     • See this PR for the full solution.

Ui component

Scenario: You are in charge of ui. During a beta testing session, your team is observing how the users use your ePiggy 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 expense 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 expense 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 EPiggySystemTest#assertCommandBoxShowsDefaultStyle() and EPiggySystemTest#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 ePiggy.

   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 ePiggy is updated.

   • Solution

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

     • Use StatusBarFooter#handleEPiggyChangedEvent(EPiggyChangedEvent) to update the number of expenses 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 EPiggySystemTest to also verify the new total number of expenses 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 ePiggy to the cloud. However, the current implementation of the application constantly saves the ePiggy 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 ePiggy storage.

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

1. Add a new method backupEPiggy(ReadOnlyEPiggy), so that the ePiggy can be saved in a fixed temporary location.

   • Hint

     • Add the API method in EPiggyStorage interface.

     • Implement the logic in StorageManager and JsonEPiggyStorage 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 expense specified in the INDEX.
Format: remark INDEX r/[REMARK]

Examples:

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

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

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 Command. Upon execution, it should just throw an Exception.

2. Modify EPiggyParser to accept a RemarkCommand.

Tests:

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

2. Add new test method to EPiggyParserTest, 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 EPiggyParser 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 EPiggyParserTest 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 expense 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 Expense 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 Expense to support a Remark field

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

Main:

1. Add getRemark() in Expense.

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 expense will be created without a remark).

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

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

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

Main:

1. Add a new JSON field for Remark.

Tests:

1. Fix invalidAndValidPersonEPiggy.json, typicalPersonsEPiggy.json, validEPiggy.json etc., such that the JSON tests will not fail due to a missing remark field.

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

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

Tests:

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

2. Try and use the method on any sample Expense 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 Expense 's remark.

Tests:

1. Modify GuiTestAssert#assertCardDisplaysPerson(…​) 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 expense.

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 profile:

• has a need to manage a significant number of contacts

• prefer desktop apps over other types

• can type fast

• prefers typing over mouse input

• is reasonably comfortable using CLI apps

Value proposition: manage contacts faster than a typical mouse/GUI driven app

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…​
* * *	user	add a new expense record	Track my usage of the expense
* * *	user	delete my expense records	remove the wrong expenses records
* * *	new user	see usage instructions	refer to instructions when I forget how to use the App
* * *	user	see my total expenditure till date or by time period	know the total amount I have spent
* *	user	see the report of my spending on specified year	know how much I spend on that year
* *	user	see the date of my spending	know when I spend a certain item
* *	user	see the percentage of the amount I spent out of my set budget	track my expenses
* *	user	receive reminders when I am approaching my budget	cut down on my expenses
* *	user	set a monthly budget	know whether I’m keeping to the budget
* *	user	see the statistics of my spendings till date	see my spending habits
* *	new user	create my personal account	make my personal expense records confidential
* *	user	login to my personal account	manage my personal expense records
* *	user	get notification when budget finishing	manage the rest of the budget well
* *	user	see the report of my spending on specified date	know how much I spend on that day
* *	user	see the report of my spending on specified month of the year	know how much I spend on that month of the year

Appendix D: Use Cases

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

Use case: Edit

MSS

1. User requests to list expenses

2. ePiggy shows a list of expenses

3. User requests to edit a specific expense in the list

4. ePiggy edits the expense

   Use case ends.

Extensions

• 2a. The list is empty.

  Use case ends.

• 3a. The given index is invalid.

  • 3a1. ePiggy shows an error message.

    Use case resumes at step 2.

Use case: View expense entry

MSS

1. User requests to list expenses.

2. ePiggy shows list of expenses.

3. User requests to view a specific expense in the list.

4. ePiggy displays the details of the specified expense.

   Use case ends.

Extensions

• 2a. The list is empty.

  Use case ends.

• 3a. The given index is invalid.

  • 3a1. ePiggy shows an error message.

    Use case resumes at step 2.

Use case: View report

MSS

1. User requests to view expenditure report of a day/month/year.

2. ePiggy shows the expenditure report for that day/month/year.

   Use case ends.

Extensions

• 1a. The given date is invalid.

  • 1a1. ePiggy shows an error message.

    Use case ends.

Use case: Set budget

MSS

1. User requests to set budget

2. ePiggy sets the input number as the budget

   Use case ends.

Extensions

• 1a. The given amount is invalid.

  • 3a1. ePiggy shows an error message.

    Use case resumes at step 1.

• 1b. User already has a budget set.

  • 1b1. ePiggy asks if user would like to overwrite old budget.

    • 1b1a. ePiggy sets a new budget based on user’s new input.

    • 1b1b. ePiggy keeps the old budget.

      Use case resumes at step 2.

Use case: Recommend

MSS

1. User requests ePiggy to recommend

2. ePiggy recommends future spendings

   Use case ends.

Extensions

• 1a. The period of expenses is less than a week.

  • 1a1. ePiggy shows an error message.

    Use case ends.

Use case: Forecast

MSS

1. User requests ePiggy to forecast future spendings

2. ePiggy gives a forecast of future spendings

   Use case ends.

Extensions

• 1a. The period of expenses is less than a week.

  • 1a1. ePiggy shows an error message.

    Use case ends.

Use case: Create new account

MSS

1. User requests create a new account

2. ePiggy requests username and password

3. ePiggy creates new user account

   Use case ends.

Extensions

• 1a. Username exists on the database.

  • 1a1. ePiggy shows an error message.

    Use case ends.

Use case: Add new expense record

MSS

1. User requests the create a new record.

2. User enters a add command with the name of item, cost, categories and date

3. ePiggy saves the record.

   Use case ends.

Extensions

• 2a. The name and date are empty.

  • 2a1. ePiggy shows an error message.

    Use case resumes at step 2.

Use case: Search expense records

MSS

1. User requests to search for an expense record.

2. ePiggy requests user to enter search command.

3. User enters search command with specific parameters.

4. ePiggy searches and displays the record(s).

   Use case ends.

Extensions

• 1a. Parameter field is empty.

  • 1a1. ePiggy lists all the expense records.

    Use case ends.

Use case: Sort expense records

MSS

1. User requests to sort expense records.

2. ePiggy requests user to enter sort command.

3. User enters sort command with specific parameters.

4. ePiggy sorts and displays the record(s).

   Use case ends.

Extensions

• 1a. Parameter field is empty.

  • 1a1. ePiggy lists all the expense records sorted by date added.

    Use case ends.

Use case: Delete expense records

MSS

1. User requests to delete expense record.

2. ePiggy requests user to enter delete command.

3. User enters delete command with index of the expense record.

4. ePiggy perform delete action

   Use case ends.

Extensions

• 1a. The period of expenses is less than a week.

  • 1a1. ePiggy shows an error message.

    Use case ends.

Use case: Login

MSS

1. ePiggy requests username and password

2. User enters username and password

3. User login success.

   Use case ends.

Extensions

• 1a. Username and password do not match.

  • 1a1. ePiggy shows an error message.

  • 1a2. ePiggy recovers from 1.

    Use case ends.

Use case: Help

MSS

1. User requests for help.

2. ePiggy displays a list of all the commands - brief description and syntax.

   Use case ends.

Use case: Notify when budget finishing

MSS

1. User budget is finishing soon

2. ePiggy shows warning message

   Use case ends.

{More to be added}

Appendix E: Non Functional Requirements

1. Should work on any mainstream OS as long as it has Java 9 or higher installed.

2. Should be able to hold up to 1000 expenses 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 than using the mouse.

{More to be added}

Appendix F: Glossary

Mainstream OS

Windows, Linux, Unix, OS-X

Private contact detail

A contact detail that is not meant to be shared with others

Appendix G: Product Survey

Product Name

Author: …​

Pros:

• …​

• …​

Cons:

• …​

• …​

Appendix H: Instructions for Manual Testing

Given below are instructions to test the app manually.

ℹ️	These instructions only provide a starting point for testers to work on; testers are expected to do more exploratory testing.

H.1. Launch and Shutdown

1. Initial launch

   1. Download the jar file and copy into an 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 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.

{ more test cases …​ }

H.2. Deleting an expense

1. Deleting an expense while all expenses are listed

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

   2. Test case: deleteExpense 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: deleteExpense 0
      Expected: No expense is deleted. Error details shown in the status message. Status bar remains the same.

   4. Other incorrect deleteExpense commands to try: deleteExpense, deleteExpense x (where x is larger than the list size) {give more}
      Expected: Similar to previous.

{ more test cases …​ }

H.3. Saving data

1. Dealing with missing/corrupted data files

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

{ more test cases …​ }