NUSSU Connect - Developer Guide

By: Team F09-1 Since: Sep 2018 Licence: MIT

1. Setting up
2. Design
3. Implementation
4. Documentation
5. Testing
6. Dev Ops
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

1. Setting up

1.1. Prerequisites

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.
IntelliJ IDE

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.

1.2. Setting up the project in your computer

Fork this repo, and clone the fork to your computer
Open IntelliJ (if you are not in the welcome screen, click File > Close Project to close the existing project dialog first)
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
Click Import Project
Locate the build.gradle file and select it. Click OK
Click Open as Project
Click OK to accept the default settings
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.

1.3. Verifying the setup

Run the seedu.address.MainApp and try a few commands
Run the tests to ensure they all pass.

1.4. Configurations to do before writing code

1.4.1. 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,

Go to File > Settings… (Windows/Linux), or IntelliJ IDEA > Preferences… (macOS)
Select Editor > Code Style > Java
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.

1.4.2. 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:

Configure the site-wide documentation settings in build.gradle, such as the site-name, to suit your own project.
Replace the URL in the attribute repoURL in DeveloperGuide.adoc and UserGuide.adoc with the URL of your fork.

1.4.3. 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).

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).

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)

1.4.4. Getting started with coding

When you are ready to start coding,

Get some sense of the overall design by reading Section 2.1, “Architecture”.
Take a look at Appendix A, Suggested Programming Tasks to Get Started.

2. Design

2.1. 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. 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 : 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

Events-Driven nature of the design

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

Figure 3. Component interactions for delete 1 command (part 1)

Note how the Model simply raises a AddressBookChangedEvent when the Address Book data are changed, instead of asking the Storage to save the updates to the hard disk.

The diagram 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 4. Component interactions for delete 1 command (part 2)

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.

2.2. UI component

Figure 5. 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.
Binds itself to some data in the Model so that the UI can auto-update when data in the Model change.
Responds to events raised from various parts of the App and updates the UI accordingly.

2.3. Logic component

Figure 6. Structure of the Logic Component

API : Logic.java

Logic uses the AddressBookParser 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 person) 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("delete 1") API call.

Figure 7. Interactions Inside the Logic Component for the delete 1 Command

Given below is the Object Diagram that shows the associations between various objects within the Logic component for the Login functionality.

Figure 8. Associations between objects in the Logic Component for Login feature

LogicManager creates a new instance of AddressBookParser, which takes in the user login input details.
This results in the simultaneous instantiation of LoginUserIdPasswordRoleCommandParser object and the calling of parse() method on the object.
From the parsing of user input, three objects, idPredicate, passwordPredicate and rolePredicate, which belongs to UserIdContainsKeywordsPredicate, UserPasswordContainsKeywordsPredicate and UserRoleContainsKeywordsPredicate respectively, are instantiated and passed as parameters in the instantiation of a LoginUserIdPasswordRoleCommand object.
Depending on the user input, some of the booleans in LoginManager may be set to true.

2.4. Model component

Figure 9. Structure of the Model Component

API : Model.java

The Model,

stores a UserPref object that represents the user’s preferences.
stores the Address Book data.
stores the Club Budget Elements Book data.
stores the Final Budgets Book data.
exposes an unmodifiable ObservableList<Person> 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.
similarly exposes an unmodifiable ObservableList<ClubBudgetElements> and ObservableList<FinalClubBudget> that can be 'observed'.
does not depend on any of the other three components.

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

Given below is the Object Diagram that shows the associations between various objects within the Model component for the Login functionality.

Figure 10. Associations between objects in the Model Component for Login feature

filteredLoginDetails will always show all accounts when ModelManager is first instantiated.
Depending on the user input during login, filteredLoginDetails will be gradually filtered according to matching user id first, followed by user password and then, user role.
Whether or not the login is a success or a failure, will depend on if there is an account left in the list after the list is filtered.
The existing user id, user password and user role fields in the filteredLoginDetails accounts list will not be edited in any way.

Given below is the Object Diagram for the various associations between objects in the Model Component for the budget command, which is the first step of th Budgeting feature

Given below is the Object Diagram for the various associations between objects in the Model Component for the calculatebudget command, which is the second step of the Budgeting feature.

filteredClubsList and filteredClubBudgetsList are empty when ModelManager is first initialised.
The details of the attributes of the ClubBudgetElements and FinalClubBudget objects stored respectively in the filteredClubsList and filteredClubBudgetsList cannot be edited in any way.

2.5. Storage component

Figure 11. 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 Address Book data in xml format and read it back.

Given below is the Object Diagram that shows the associations between various objects within the Storage component for the new account creation functionality.

Figure 12. Associations between objects in the Storage Component for account creation feature

XmlAccount is instantiated, with the appropriate account details as parameters for the new XmlAccount object.
An List<XmlAccount> object is instantiated, with the previous XmlAccount object containing the new account’s details to be added into the List<XmlAccount> object in XmlSerializableLoginBook.
The resulting LoginBook is then serialized to Xml format in XmlSerializableLoginBook.
With a new XmlSerializableLoginBook object instantiated with the account details in a LoginBook object, the XmlSerializableLoginBook object is then passed as a parameter when the save method in XmlLoginBookStorage is called, to save to a location according the the Path specified.

2.6. Common classes

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

3. Implementation

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

3.1.1. Current Implementation

The login mechanism utilizes an existing Java library, FilteredList, in order to filter out the relevant account that is associated with an instance of a successful login. An object belonging to the FilteredList class, called filteredLoginDetails, is instantiated at the start of the application. The filteredLoginDetails object initially contains a complete list of all existing accounts stored in LoginBook. There is one crucial operation in FilteredList, which is often used:

FilteredList#setPredicate(predicate) — Filters accounts in filteredLoginDetails according to the predicates determined after the user inputs their login details.

ModelManager implements updateFilteredLoginDetailsList(Predicate<LoginDetails> predicate) and getFilteredLoginDetailsList() found in the Model interface. getFilteredLoginDetailsList() is called when the list of accounts in LoginBook is filtered to the extent where only one or no account remains in the list.

Given below is an example usage scenario and how the login mechanism behaves at each step. The sequence diagram below demonstrates the flow of operation and interaction between the Logic and Model component in the login mechanism. The diagram shows what happens when the user inputs the correct login details.

Step 1. You launch the application for the first time. The filteredLoginDetails object will be initialized with a list of all the accounts in LoginBook.

Step 2. You execute login A1234568M zaq1xsw2cde3 member command in the input box that matches an account in LoginBook. LogicManager then calls ParseCommand(login A1234568M zaq1xsw2cde3 member) in AddressBookParser.

Step 3. AddressBookParser instantiates the LoginUserIdPasswordRoleCommandParser object and simultaneously calls the parse(args) method, returning an LoginUserIdPasswordRoleCommand object with the user input, parsed, to AddressBookParser and LogicManager.

Step 4. LogicManager calls the execute() method in LoginUserIdPasswordRoleCommand. Next, LoginUserIdPasswordRoleCommand calls updateFilteredLoginDetailsList(updatedIdPredicate) in Model with the computed predicate from user ID field input.

Step 5. Model calls setPredicate(updatedIdPredicate) in FilteredList, filtering accounts whose user Id is a mismatch with updatedIdPredicate. filteredLoginDetails is updated as shown below.

Step 6. LoginUserIdPasswordRoleCommand calls updateFilteredLoginDetailsList(updatedPassPredicate) in Model with the computed predicate from user password field input.

Step 7. Model calls setPredicate(updatedPasswordPredicate) in FilteredList, which then further filters out accounts whose password is a mismatch with updatedPasswordPredicate. filteredLoginDetails is further updated as shown below.

Step 8. LoginUserIdPasswordRoleCommand calls updateFilteredLoginDetailsList(updatedRolePredicate) in Model with the computed predicate from user role field input.

Step 9. Model calls setPredicate(updatedRolePredicate) in FilteredList, which then further filters out accounts whose role is a mismatch with updatedRolePredicate. filteredLoginDetails is further updated as shown below.

After step 9 is done, there should only be one account left in the list, assuming that the user input the correct login details. As the loginbook does not allow duplicate accounts with the same user ID field as another account, there should not be two or more accounts left in the list.

In step 2, if you execute login A1234566M zaq1xsw2cde janitor command instead, the application will continue with steps 2 to 7, but instead of one account remaining at the end of the filtering process, there will be no account in the updated list as shown in the image below.

In step 2, if you give a blank input for the login command instead, the application will throw a new ParseException and consider the login attempt as unsuccessful and initiate a new pop-up window asking you for input of login credentials again, as shown in the image below.

In step 2, if the input has either the id, password or role missing instead, the application will throw ParseException, consider the login attempt as unsuccessful and initiate a new pop-up window asking you for input of login credentials again, as shown in the image below.

In all cases where you input either the wrong ID, password, or role, there will be no account left in the account list when getFilteredLoginDetailsList method in Model is called. The isLoginSuccessful boolean in LoginManager will be set to false via the setter method, setIsLoginSuccessful in LoginManager. This is done by the checkUpdatedAccountListSetLoginCondition method in LoginUserIdPasswordRoleCommand. The initializeLoginProcess method in MainWindow will be called repeatedly until isLoginSuccessful is set to true. The sequence diagram below shows the high level workflow of the login mechanism in the event of log-in failure.

The activity diagrams below shows the overall picture of how the login mechanism works.

3.1.2. Design Considerations

This section touches on the design considerations encountered during the project in the implementation of the login feature, different alternatives in different design aspects, and its advantages and disadvantages.

Alternative 1 (current choice): Saves login credentials in loginbook.xml in XML format.
- Pros: Easier to read, and versioning is possible.
- Cons: XML data file takes up more storage space.
Alternative 2: Saves login credentials using JSON.
- Pros: Does not take up a lot of space.
- Cons: Harder to read.

3.2. Budgeting Feature

3.2.1. Current Implementation

This feature has been implemented through 3 separate commands, each dealing with a separate stage in the calculation and subsequent allocation of budgets by the NUSSU Executive Committee to all the clubs that submit the data required to calculate the budget. The three commands are: budget - which handles the submission of data by the club treasurer required to calculate the budget for that club, calculatebudget - which is to be used only by the NUSSU Executive Committee members in order to calculate the budgets for each club and viewbudget - which lists the final budgets of all the clubs.

Submission of Data

Given below is an example usage scenario and the behaviour at each step of the budget command.

Step 1. The user launches the application for the first time. 'filteredClubsList' will be initialised with an empty list of all the clubs' budget calculation data in the address book. Similarly 'filteredClubBudgets' will be initialised with an empty list of all the club budgets in the address book.

Step 2. The user (a club member) executes budget c/Computing Club t/200 e/5 command in order to submit the data for the calculation of her club’s budget. The 'LogicManager' then calls the 'parseCommand' in the 'AddressBookParser'.

Step 3. The 'AddressBookParser' then returns a new 'BudgetCommandParser', if the user is of the member role. (Else a parse exception is thrown.)

Step 4. The 'BudgetCommandParser' parses the command to be executed and creates a 'ClubBudgetElements' object called 'club' with the club’s name, the expected turnout and the number of events, as specified by the user. Finally the 'BudgetCommand' is called with 'club' as the argument.

Step 5. The 'BudgetCommand' checks whether the 'club' is a duplicate and if it is not, the 'BudgetCommand' calls the 'addClub' method in 'Model' with 'club' as the argument.

Step 6. 'Model' calls 'addClub' in 'ReadOnlyClubBudgetElementsBook' and indicates that the club budget elements book’s status has changed.

Step 7. 'ReadOnlyClubBudgetElementsBook' calls the 'addClub' command on an object 'clubs' of the 'UniqueClubsList' class, thus adding the required club’s data to the club budget elements book.

Step 8. Finally a success message is displayed with the details that have been entered by the user.

As mentioned in Step 5, had the user entered a club name that already existed in the list of clubs in the address book, then a duplicate club budget elements message would be shown, prompting the user to edit their entered command and try again. Execution of subsequent steps would be stopped until the user entered a unique club name.

The image below is the sequence diagram for the functioning of the budget command:

Calculation and allocation of budgets

Given below is an example usage scenario and the behaviour at each step of the calculatebudget command.

Step 1. 'filteredClubsList' will no longer be an empty list, and will now contain the budget calculation data of the clubs that have been added using the budget command.

Step 2. The user (a NUSSU treasurer) executes the calculatebudget b/50000 command with '50000' as the total available budget, in order to calulate and allocate all the clubs' budgets. The 'LogicManager' then calls the 'parseCommand' in the 'AddressBookParser'.

Step 3. The 'AddressBookParser' then returns a new 'BudgetCalculationCommandParser', if the user is of the role treasurer. (Else a parse exception is thrown.)

Step 4.'BudgetCalculationCommandParser' parses the command and creates a 'TotalBudget' object called 'totalBudget' with the total available budget specified by the user. Finally the 'BudgetCalculationCommand' is called with 'totalBudget' as the argument.

Step 5. The 'BudgetCalculationCommand' checks whether the 'totalBudget' is a negative number. It also checks whether the budgets have already been calculated before using the getHaveBudgetsBeenCalculated method of the 'BudgetCalculationManager'. It also checks whether the clubBudgetElementsBook is empty. If none of this are true, then the 'filteredClubsList' is iterated through to calculate the budget, an object 'toAdd' of the 'FinalClubBudget' class, of each club in the list. When the budget for a club has been calculated, the 'BudgetCalculationCommand' calls the 'addClubBudget' method in Model with 'toAdd' as the parameter.

Step 6. 'Model' calls 'addClubBudget' in 'ReadOnlyFinalBudgetBook' and indicates that the finalBudgetsBook’s status has changed.

Step 7. 'ReadOnlyFinalBudgetBook' calls the 'addClubBudget' command on an object 'clubBudgets' of the 'UniqueClubBudgetsList' class, thus adding the required club’s allocated budget to the finalClubBudgetsBook. The process repeats until the budget for every club in the 'filteredClubsList' has been calculated and allocated.

Step 8. Once the budget for every club has been allocated a success message is displayed, telling the user that the budgets have been calculated.

The image below is a sequence diagram for the 'BudgetCalculationCommand'

Viewing the allocated budgets

Given below is an example usage scenario and the behaviour at each step of the viewbudget command.

Step 1. 'filteredClubBudgetsList' will no longer be an empty list, and will now contain the final budgets that have been allocated to each of the clubs in the 'filteredClubsList'.

Step 2. The user (a NUSSU treasurer, a club member or even a club’s President) executes the viewbudget c/Computing Club command to view the budget allocated to the club that she has specified (in this case the Computing Club). The 'LogicManager' then calls the 'AddressBookParser'.

Step 3. The 'AddressBookParser' then returns a new ViewClubBudgetsCommandParser' if the user role is set to either member, treasurer or president.

Step 4. The 'ViewClubBudgetsCommandParser' then creates a 'ClubName' object called clubName. Finally the 'ViewClubBudgetsCommand' is called with 'clubName' as the argument.

Step 5. 'ViewClubBudgetsCommand' checks whether the budgets have been calculated already. If they have not, an error message is shown to the user. If they have, then the 'filteredClubBudgetsList' is looped through to find a 'FinalClubBudget' object with the same 'ClubName' as the 'clubName' that is specified by the user (in this case 'Computing Club'). If it is found, then the associated 'allocatedBudget' of that 'FinalClubBudget' object is displayed to the user. Else a message saying that the specified club’s budget does not exist is shown to the user.

The image below is a sequence diagram for the 'ViewClubBudgetsCommand'

3.2.2. Design Considerations

Aspect: How club budget elements data and final club budgets data is stored

Alternative 1 (current choice): Saving club budget elements data and final club budgets in budgetelements.xml and budgets.xml respectively in XML format.
- Pros: It is easy to read.
- Cons: XML data files takes up more storage space, also more verbose.
Alternative 2: Saving club budget elements data and final club budgets using JSON.
- Pros: Faster and takes less storage space
- Cons: Less intuitive or readable since items are presented in a manner that is more similar to the code.

Aspect: How the final club budgets are stored

Alternative 1 (current choice): Currently the final club budgets are stored in a list (which is accessed when using the viewbudget command).
- Pros: Easier to implement, with respect to the project’s time constraints
- Cons: Not a good choice with respect to time complexity. If the list of final club budgets is very large, then looping through it in worst case time complexity of O(N) to find the desired club’s budget, is very slow. Thus not allowing the NFR of speed to be achieved.
Alternative 2: Using a map to store the final club budgets
- Pros: Far faster to search for the desired club’s final budget given that Club Names must be unique.
- Cons: Would take longer to implement.

3.2.3. Possible Extensions

Implementing an editbudget command to allow the club members to edit the budget calculation data until the treasurers have calculated and allocated the budgets.
Allowing the NUSSU treasurers to calculate and allocate the budgets multiple times. This will allow them to change the total budget as and when needed and also allow club members to keep submitting their budget calculation data.

3.3. Search Pruning Feature

The Search Pruning mechanism is facilitated by the SearchHistoryManager class, and within it is a searchHistoryStack that stores Predicate objects. Predicate objects are used to filter FilteredList objects by calling the setPredicate() method of FilteredList. By storing Predicate objects in SearchHistoryManager, it stores the search logic that was previously used by the FilteredList object, and hence, simulates the storing Search History without storing the actual data.

In NUSSU Connect, the main SearchHistoryManger object is in ModelManager and it stores Predicate<Person> objects used for the filtering of filteredPersons list.

If you want to utilize SearchHistoryManager for your own use case, you can initialize a new SearchHistoryManager object with its' generic constructor.

3.3.1. Current Implementation

The main implementation behind SearchHistoryManager is a Stack Data Structure and the following 4 methods of SearchHistoryManager are exposed for your usage

executeNewSearch(Predicate<T> predicate)
updates system search logic to the next state and returns a Predicate object storing the system search logic after the update.
revertLastSearch()
reverts system search logic to the previous state and returns a Predicate object storing the system search logic after revert.
clearSearchHistory()
clears all system search logic from in-app memory.
isEmpty()
returns true if searchHistoryStack is empty.

Given below are illustrations to help you understand how the first three method works internally. But before carrying on, you need to take note of the following.

In the diagrams, 'UP' is the short-form for User Predicate and 'SP' is the short-form for System Predicate. User Predicate stores the logic specified by the user and it is not the actual search logic used for filtering of FilteredList objects. On the other hand, System Predicate stores the search logic for the system and it will be used to filter FilteredList objects.

User Predicate and System Predicate are not actual Classes and they are simply there to help simplify the explanation. In the actual implementation, there is no way to differentiate one from the other.

executeNewSearch(Predicate<T> predicate)

Upon calling this method, there will be two different situations

Situation 1: searchHistoryStack is empty
Upon receiving a new User Predicate, SearchHistoryManager will simply push the new User Predicate into searchHistoryStack as a System Predicate.

Situation 2: searchHistoryStack is not empty
Before pushing the new Predicate into the stack, SearchHistoryManager will first retrieve the System Predicate object at the top of the stack. After retrieving it, it will call the and() method with the User Predicate, creating a new System Predicate which will then be pushed into the top of the stack.

This method will return the new System Predicate at the top of the stack.

revertLastSearch()

This method will pop the System Predicate at the top of the stack. In the event that the stack is already empty, this method will throw EmptyHistoryException.

If the stack is not empty after the pop, this method will return the System Predicate at the top of the stack. Else, it will return a Predicate object with a search logic that always defaults to true.

clearSearchHistory()

This method will simply empty the stack.

How SearchHistory

The following sequence diagrams shows you how the IncludeNameFindCommand and UndoFind commands utilize SearchHistoryManager to perform Search Pruning. Other variations of FindCommand works similarly to IncludeNameFindCommand and the sequence diagram for IncludeNameFindCommand is also relevant to them.

IncludeNameFind command

UndoFind command

3.3.2. Design Considerations

Aspect: What data is stored in search history stack

Alternative 1(current choice): Save a Stack of Predicate objects
- Pros:
  1. Does not need to store the data in search history explicitly which saves memory
  2. SearchHistoryManager class is reusable for any Search Pruning done with Predicate
- Cons:
  1. Developers need to understand how Predicate works before utilizing SearchHistoryManager to perform Search Pruning.
  2. Predicate objects by itself does not perform the Search Pruning. We have to make an additional call to the setPredicate() method of the FilteredList class with the Predicate object.
Alternative 2: Save a Stack of Lists containing Person objects in search history
- Pros:
  1. It is easy to understand from the code that we are filtering according to Person objects.
- Cons:
  1. More memory is required as Person objects has to be duplicated multiple times into a new Lists.
  2. SearchHistoryManager can only be used for Search Pruning on objects that is a Person.

Aspect: How the Predicate at the top of the Stack is retrieved from SearchHistoryManager

Alternative 1(current choice): Predicate is returned from the methods executeSearch() and revertLastSearch()
- Pros:
  1. No need for an extra method call to retrieve system search logic in the form of Predicate from SearchHistoryManager.
- Cons:
  1. No clear distinction between Update and Retrieval of system search logic.
Alternative 2: Predicate is not returned from the methods executeSearch() and revertLastSearch(), but is instead retrieved with another method.
- Pros:
  1. Clearer distinction between Update and Retrieval of system search logic.
- Cons:
  1. Need to perform 2 method calls separately to retrieve Predicate object from SearchHistoryManager after an update to search logic.
  2. Need to implement another method specifically for retrieval of Predicate object.
  3. Other developers utilizing SearchHistoryManger need to remember that they need to retrieve Predicate object from SearchHistoryManager separately after an update to search logic.

3.4. Add Skill Level Command

3.4.1. Current Implementation

The add skill mechanism builds on the addressBookParser. This as well as it’s subclass addSkillCommandParser ensures that the correct number of arguments is given to the command.

You can observe how the application Logic handles the request to change a skill in one particular scenario in the following steps:

Step 1. The user launches the application. The application boots up and lists all members.

Step 2. The user locates the person he wants to add on at Index 4. They execute the asl 4 s/Photography l/60 command.

Step 3.'LogicManager' calls the 'parseCommand' in the 'AddressBookParser', which calls AddSkillCommandParser to parse it.

Step 4. After parsing, the command is sent to the Model which alters the Person object by modifying their Skill and SkillLevel properties.

Step 5. The result is encapsulated as a CommandResult object which is passed back to the UI.

The following is a sequence diagram illustrating the above.

Usage:

Before executing the command:

After executing the command:

3.4.2. Alternate implementations

We considered two different ways to implement the Skill Class.

Alternative 1: Combining both Skill and SkillLevel properties together into a single class.
- Pros: Resembles the real world, as there is a one-to-one mapping of Skill to SkillLevel.
- Cons: Harder to test, and violates Single Responsiblity Principle.
Alternative 2 (Current Choice): Separating the Skill and SkillLevel classes into different classes.
- Pros: Easier to test.
- Cons: Adds to the number of classes unnecessarily.

3.4.3. Possible extensions

One possiblilty is to enhance the add command such that skills can be added together with the rest of the information during addition of personal information.
Another is to enhance the edit command, possibly depreciating the use of the add skill level command.
Another is to enhance the storage such that multiple skills can be added per person.

3.5. Sort feature

This feature was implemented by implementing custom comparators in Person class. You will be able to compare the values in each person which are used as arguments to the Sort, which is a method of all instances of List.

A FilteredList (unmodifiable) is obtained from the model and is placed into an ArrayList, which is modifiable.
Sort is called on the list, using custom comparators which can be found in the Person Class.
The items are deleted from the model and are replaced in the order of the ArrayList.

3.5.1. Possible extensions

Currently, the find command doesn’t work with the Sort Command. The two commands used together would be quite powerful, so making them work together would be top priority for v2.0.
It should also be possible to sort by reverse, and sort by multiple criteria at once.

3.6. Undo/Redo feature

3.6.1. Current Implementation

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

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

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

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

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

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

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

If a command fails its execution, it will not call Model#commitAddressBook(), so the address book state will not be saved into the addressBookStateList.

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

If the currentStatePointer is at index 0, pointing to the initial address book state, then there are no previous address book states to restore. The undo command uses Model#canUndoAddressBook() 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#redoAddressBook(), which shifts the currentStatePointer once to the right, pointing to the previously undone state, and restores the address book to that state.

If the currentStatePointer is at index addressBookStateList.size() - 1, pointing to the latest address book state, then there are no undone address book states to restore. The redo command uses Model#canRedoAddressBook() 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 address book, such as list, will usually not call Model#commitAddressBook(), Model#undoAddressBook() or Model#redoAddressBook(). Thus, the addressBookStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitAddressBook(). Since the currentStatePointer is not pointing at the end of the addressBookStateList, all address book states after the currentStatePointer will be purged. 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:

3.6.2. Design Considerations

Aspect: How undo & redo executes

Alternative 1 (current choice): Saves the entire address book.
- Pros: Easy to implement.
- Cons: May have performance issues in terms of memory usage.
Alternative 2: Individual command knows how to undo/redo by itself.
- Pros: Will use less memory (e.g. for delete, just save the person 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 address book 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 VersionedAddressBook.
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.

3.7. 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 3.8, “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

3.8. Configuration

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

4. Documentation

We use asciidoc for writing documentation.

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

4.1. 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.

4.2. Publishing Documentation

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

4.3. 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.

Follow the instructions in UsingGradle.adoc to convert the AsciiDoc files in the docs/ directory to HTML format.
Go to your generated HTML files in the build/docs folder, right click on them and select Open with → Google Chrome.
Within Chrome, click on the Print option in Chrome’s menu.
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 13. Saving documentation as PDF files in Chrome

4.4. 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

4.5. 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

4.6. 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.

5. Testing

5.1. 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)

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)

5.2. Types of tests

We have two types of tests:

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.
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

5.3. 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.

6. Dev Ops

6.1. Build Automation

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

6.2. Continuous Integration

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

6.3. Coverage Reporting

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

6.4. 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.

6.5. Making a Release

Here are the steps to create a new release.

Update the version number in MainApp.java.
Generate a JAR file using Gradle.
Tag the repo with the version number. e.g. v0.1
Create a new release using GitHub and upload the JAR file you created.

6.6. Managing Dependencies

A project often depends on third-party libraries. For example, Address Book 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. Include those libraries in the repo (this bloats the repo size)
b. 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:

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”.
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 2.3, “Logic component” before attempting to modify the Logic component.

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 persons 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 address book, 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 2.4, “Model component” before attempting to modify the Model component.

Add a removeTag(Tag) method. The specified tag will be removed from everyone in the address book.
- 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 person, and Person allows you to update the tags.
- Solution
  
  Implement a removeTag(Tag) method in AddressBook. Loop through each person, and remove the tag from each person.
  
  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.

`Ui` component

Scenario: You are in charge of ui. During a beta testing session, your team is observing how the users use your address book 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 person in the list. Your job is to implement improvements to the UI to solve all these problems.

Do take a look at Section 2.2, “UI component” before attempting to modify the UI component.

Use different colors for different tags inside person 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.
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.
Modify the StatusBarFooter to show the total number of people in the address book.

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 address book is updated.
- Solution
  
  Modify the constructor of StatusBarFooter to take in the number of persons when the application just started.
  
  Use StatusBarFooter#handleAddressBookChangedEvent(AddressBookChangedEvent) to update the number of persons 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 persons 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 address book to the cloud. However, the current implementation of the application constantly saves the address book 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 address book storage.

Do take a look at Section 2.5, “Storage component” before attempting to modify the Storage component.

Add a new method backupAddressBook(ReadOnlyAddressBook), so that the address book 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 person specified in the INDEX.
Format: remark INDEX r/[REMARK]

Examples:

remark 1 r/Likes to drink coffee.
Edits the remark for the first person to Likes to drink coffee.
remark 1 r/
Removes the remark for the first person.

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:

Add a RemarkCommand that extends Command. Upon execution, it should just throw an Exception.
Modify AddressBookParser to accept a RemarkCommand.

Tests:

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

Modify RemarkCommand to take in an Index and String and print those two parameters as the error message.
Add RemarkCommandParser that knows how to parse two arguments, one index and one with prefix 'r/'.
Modify AddressBookParser to use the newly implemented RemarkCommandParser.

Tests:

Modify RemarkCommandTest to test the RemarkCommand#equals() method.
Add RemarkCommandParserTest that tests different boundary values for RemarkCommandParser.
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 person later.

Main:

Add a Label with any random text inside PersonListCard.fxml.
Add FXML annotation in PersonCard to tie the variable to the actual label.

Tests:

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:

Add Remark to model component (you can copy from Address, remove the regex and change the names accordingly).
Modify RemarkCommand to now take in a Remark instead of a String.

Tests:

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:

Add getRemark() in Person.
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 person will be created without a remark).
Modify SampleDataUtil to add remarks for the sample data (delete your addressBook.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:

Add a new Xml field for Remark.

Tests:

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:

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

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

Tests:

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:

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

Tests:

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…

Priority	As a …	I want to …	So that I can…
`* * *`	executive officer of NUSSU	view which other committees my applicant has applied for	deconflict with the other members of the Executive Committee
`* * *`	executive officer of NUSSU	view the number of applicants with the relevant skills	assign them to the relevant subcommittees
`* * *`	member of NUSSU	find out how to contact another member within NUSSU	work more efficiently with them
`* * *`	someone that takes charge of sponsors for events hosted by NUSSU	filter my search such that I would be only looking at the list of sponsors	not need to look through the whole list of contact details
`* * *`	event organizer that is trying to find the contact details of some very specific group of people	have a search and filter function that is flexible enough	find all the search requirements can be done on the application without needing me to look through the whole list
`* * *`	any user trying to filter the list of contact details	have an intuitive way to filter a large list of people	so that I can get the information that I want easily and quickly
`* * *`	forgetful user utilizing the newly implemented search pruning feature	keep track of my past search commands	so that I would not need to commit what I typed to memory
`* * *`	member of the NUSSU treasury	have a budgeting function	fairly allocate budgets to the different clubs/projects
`* * *`	treasurer of a club	view the budget allocated to our club	discuss with my teammates and seek more funds if necessary
`* * *`	treasurer of a club	be able to store the data about how many members there are in my club, how many events we are planning to hold, and the expected turn out	be allocated a fair budget by the NUSSU treasury
`* * *`	treasurer of a club	use a budgeting function	plan the internal events of my club efficiently
`* * *`	member of the NUSSU treasury	view requests for grants from the clubs	allocate them the grant if the request is accepted by the NUSSU
`* * *`	executive member of NUSSU	log into the application	gain secure access to the application
`* * *`	executive member of NUSSU	create a new account for the application with my relevant role	gain access to certain features of the application relevant to my role when I log in using the created account details
`* * *`	executive member of NUSSU	log into the application specific to my role	gain access to certain features of the application relevant to my role when I log in
`* *`	general secretary of NUSSU	have the option to backup all, or even specific segments of application data into a data file	recover the required segments of data when there is an accidental deletion of data
`* *`	general secretary of NUSSU	view a list of dates reserved for committee meetings planned beforehand	prepare for the meetings adequately
`* *`	executive member of NUSSU	pitch in proposal ideas into the proposal suggestions section through the community proposal voting system	find out just how popular my proposals are through the number of upvotes it receives
`* *`	executive member of NUSSU	edit current proposal ideas in the proposals section	have the option to refine current proposals
`* *`	executive member of NUSSU	delete selected proposal ideas in the proposals section	have the option to remove irrelevant proposals
`* *`	executive member of NUSSU	view the list of proposals currently suggested in the proposals section and upvote those that I like	find out more about the current proposals in place and express my favor in a particular proposal
`* *`	executive member of NUSSU	filter and search for proposal ideas based on keywords	do not have to waste time searching through all the proposals just to find the one I want
`* *`	student welfare secretary of NUSSU	view statistics showing the number of students who signed up for student welfare packs	plan student welfare goodie events better
`* *`	general secretary of NUSSU	delete selected proposal ideas in the proposals section	have the option to remove irrelevant proposals
`* *`	student life secretary of NUSSU	keep track of updated statistics showing the number of students in each faculty	plan and balance the events geared towards a specific faculty
`* *`	someone that keeps track of the finances for hosting events	an application that helps me simplify the process(Excel)	do my work efficiently
`* *`	someone that records what was discussed in a meeting	be able to keep a record of what everyone said	use it as a future reference for further discussion
`* *`	someone that constantly sends email to other members of NUSSU/ Sponsors/ Public	have an access to multiple different templates of emails	focus more on writing the content of the email instead of spending too much time on crafting the overall structure

* * *

executive officer of NUSSU

view which other committees my applicant has applied for

deconflict with the other members of the Executive Committee

* * *

executive officer of NUSSU

view the number of applicants with the relevant skills

assign them to the relevant subcommittees

* * *

member of NUSSU

find out how to contact another member within NUSSU

work more efficiently with them

* * *

someone that takes charge of sponsors for events hosted by NUSSU

filter my search such that I would be only looking at the list of sponsors

not need to look through the whole list of contact details

* * *

event organizer that is trying to find the contact details of some very specific group of people

have a search and filter function that is flexible enough

find all the search requirements can be done on the application without needing me to look through the whole list

* * *

any user trying to filter the list of contact details

have an intuitive way to filter a large list of people

so that I can get the information that I want easily and quickly

* * *

forgetful user utilizing the newly implemented search pruning feature

keep track of my past search commands

so that I would not need to commit what I typed to memory

* * *

member of the NUSSU treasury

have a budgeting function

fairly allocate budgets to the different clubs/projects

* * *

treasurer of a club

view the budget allocated to our club

discuss with my teammates and seek more funds if necessary

* * *

treasurer of a club

be able to store the data about how many members there are in my club, how many events we are planning to hold, and the expected turn out

be allocated a fair budget by the NUSSU treasury

* * *

treasurer of a club

use a budgeting function

plan the internal events of my club efficiently

* * *

member of the NUSSU treasury

view requests for grants from the clubs

allocate them the grant if the request is accepted by the NUSSU

* * *

executive member of NUSSU

log into the application

gain secure access to the application

* * *

executive member of NUSSU

create a new account for the application with my relevant role

gain access to certain features of the application relevant to my role when I log in using the created account details

* * *

executive member of NUSSU

log into the application specific to my role

gain access to certain features of the application relevant to my role when I log in

* *

general secretary of NUSSU

have the option to backup all, or even specific segments of application data into a data file

recover the required segments of data when there is an accidental deletion of data

* *

general secretary of NUSSU

view a list of dates reserved for committee meetings planned beforehand

prepare for the meetings adequately

* *

executive member of NUSSU

pitch in proposal ideas into the proposal suggestions section through the community proposal voting system

find out just how popular my proposals are through the number of upvotes it receives

* *

executive member of NUSSU

edit current proposal ideas in the proposals section

have the option to refine current proposals

* *

executive member of NUSSU

delete selected proposal ideas in the proposals section

have the option to remove irrelevant proposals

* *

executive member of NUSSU

view the list of proposals currently suggested in the proposals section and upvote those that I like

find out more about the current proposals in place and express my favor in a particular proposal

* *

executive member of NUSSU

filter and search for proposal ideas based on keywords

do not have to waste time searching through all the proposals just to find the one I want

* *

student welfare secretary of NUSSU

view statistics showing the number of students who signed up for student welfare packs

plan student welfare goodie events better

* *

general secretary of NUSSU

delete selected proposal ideas in the proposals section

have the option to remove irrelevant proposals

* *

student life secretary of NUSSU

keep track of updated statistics showing the number of students in each faculty

plan and balance the events geared towards a specific faculty

* *

someone that keeps track of the finances for hosting events

an application that helps me simplify the process(Excel)

do my work efficiently

* *

someone that records what was discussed in a meeting

be able to keep a record of what everyone said

use it as a future reference for further discussion

* *

someone that constantly sends email to other members of NUSSU/ Sponsors/ Public

have an access to multiple different templates of emails

focus more on writing the content of the email instead of spending too much time on crafting the overall structure

Appendix D: Use Cases

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

Use case: Delete person

MSS

User requests to list persons
NUSSU-Connect shows a list of persons
User requests to delete a specific person in the list
NUSSU-Connect deletes the person

Use case ends.

Extensions

2a. The list is empty.

Use case ends.
3a. The given index is invalid.
- 3a1. NUSSU-Connect shows an error message.
  
  Use case resumes at step 2.

D.1. Use case: Sort by suitability by skill

MSS

User indicates he wants to sort by skills
NUSSU-Connect lists available users.
User indicates that he wants to sort by skill.
NUSSU-Connect sorts all Persons in the application.

Use case ends.

Extensions

2a. User can sort by ascending or descending order

Use case ends.
2b. User can see all above a certain threshold

Use case ends.

D.2. Use case: Add Skill

MSS

User indicates he wants to add skill
NUSSU-Connect lists available persons
User indicates person, skill, and skill level to add
NUSSU-Connect confirms addition

Use case ends.

D.3. Use case: Intuitive Filtering of Large Number of Contacts

MSS

User requests application to display list of contacts
System returns list of contacts
User requests to find a specific group of people from list of contacts
System returns new List of Contacts filtered according to previous List
Steps 3 - 4 are repeated until user found the desired group of people
User found the group of people that he/she is looking for

Use case ends.

Extensions

4a. User makes an error and request to revert to previous List
- 4a1. System reverts and displays the previous List
  
  Use case resumes at Step 3.
3b. User request to revert List to initial state before filtering
- 3b1. System reverts List to initial state.
  
  Use case ends.

D.4. Use case: Excluding specific people from displayed list

MSS

User requests application to display list of contacts
System returns list of contacts
User requests to exclude a specific group of people from list of contacts
System returns new List of contacts according to the criteria set by the user

Use case ends

D.5. Use case: Log into system and multi user access level

System: NUSSU Connect Application
Actor: Typical NUSSU member
MSS

System prompts user to login first by entering login credentials
User types in login credentials along with the login command
System queries against login book and authorizes the user a specific level of access to NUSSU-Connect depending on user role

Use case ends.

Extensions

2a. User types in wrong password, user ID or user role
- 2a1. System continues to prompt user for login credentials before giving access to user
  
  Use case ends.
2b. User decides not to log into the application and closes the login dialog box
- 2b1. System performs a system exit and application is exited
  
  Use case ends.

D.6. Use case: Create new user accounts

System: NUSSU Connect Application
Actor: Typical NUSSU member
MSS

User types in command to create a new account with chosen user ID, password and role
System creates new account with chosen login details, and shows successful execution message

Use case ends.

Extensions

1a. User creates a new account with a user ID which already exists
- 1a1. System shows error message to user and does not create a new account
  
  Use case ends.
1b. User types in an invalid user role
- 1b1. System shows error message to user and and shows user role constraints message
  
  Use case ends.

D.7. Use Case: Submitting the budget calculation data for a club

System: NUSSU-Connect Application
Actor: Club Member
MSS

User types in command to submit new budget calculation data with the club name, expected turnout and number of events.
System creates a new club budget elements object with the specified details and shows a successful execution message.

Use case ends.

Extensions

1a. User tries to submit budget calculation data for a club that already exists
- 1a1. System shows an error message to user and does not create a new club budget elements object until the user specifies a unique club name.
1b. User types in invalid club name/ expected turnout/ number of events *
- 1b1. System shows error message to the user and shows the appropriate constraints message.
  
  Use case ends.

D.8. Use Case: Calculating and allocating the final budgets to all the clubs

System: NUSSU-Connect Application
Actor: NUSSU Treasurer
MSS

User types in command to calculate and allocate the budgets to all the clubs, with a total available budget.
System calculates and allocates the final budgets to all the clubs and shows a successful execution message.

Use case ends.

Extensions

1a. User tries to calculate budgets when no club members have yet submitted the budget calculation data
- 1a1. System shows an error message to user and does not calculate and allocate the final budgets until some budget calculation data has been submitted.
1b. User types in invalid total budget *
- 1b1. System shows error message to the user and shows the appropriate constraints message.
1c. User tries to use the budget calculation command after having already used it once before *
- 1c1. System shows error message to the user and does not calculate and allocate the budgets again.
  
  Use case ends.

D.9. Use Case: Viewing the final budget allocated to a club

System: NUSSU-Connect Application
Actor: Club Member, NUSSU Treasurer or Club President
MSS

User types in command to view the budget for a club, with the name of the club.
System displays the final budget of the specified club.

Extensions

1a. User tries to view the final budget allocated to a club before the budgets have even been allocated.
- 1a1. System shows an error message to user.
1b. User types in in an invalid club name. *
- 1b1. System shows error message to the user that the club entered does not exist in NUSSU-Connect’s memory.
  
  Use case ends.

{More to be added}

Appendix E: Non Functional Requirements

Must be able to accommodate the contact details of everyone in NUSSU + 1000 extra contact details.
Only the president of NUSSU should be able to create an account.
Passwords must be encrypted.
All commands must be completed within 1 second.
The single and multi-input commands phrases should be easy to remember and intuitive to understand what they mean.

{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.

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

Initial launch
1. Download the jar file and copy into an empty folder
2. Double-click the jar file
3. Log in with the default account credentials
  Expected: Shows the GUI with a set of sample contacts. The window size may not be optimum.
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.
3. Log into the application again with the relevant account details.
  Expected: The most recent window size and location is retained.

H.2. Creating an account

Creating a new account with the createaccount command
1. Prerequisites: Need to be logged in as president role.
2. Test case: createaccount A1234566M zaq1xsw2cde3 member
  Expected: A new account containing login details matching user input is created. A successful creation of account message is shown in the results display.
3. Test case: createaccount A1234567M zaq1xsw2cde3 member
  Expected: Account is not created. Error details shown in results display.
4. Other incorrect delete commands to try: createaccount, createaccount a1234566m zaq1xsw2cde3 member, createaccount A1234566M zaq1xsw2cde3 janitor, createaccount zaq1xsw2cde3 member, createaccount A1234566Mzaq1xsw2cde3member Expected: Similar to previous.

H.3. Finding a Person with a certain tag in the displayed list

Finding a person while all persons are listed
1. Prerequisites: List all persons using the list command.
2. Test case: find \tag friends
  Expected: All contacts with the tag friends is shown in the displayed list. Other contacts without the tag friends will be removed from the displayed list. Tag Keywords History with '+friends' message is shown in the results display
3. Test case: find \tag
  Expected: Invalid Command Format. Error details shown in results display.

H.4. Excluding a Person with a certain name from displayed list

Excluding a person while all persons are listed
1. Prerequisites: List all persons using the list command.
2. Test case: find \exclude Alex
  Expected: All contacts with the name Alex(case-insensitive) is removed from the displayed list. Name Keywords History with '-alex' message is shown in the results display
3. Test case: find \exclude
  Expected: Invalid Command Format. Error details shown in results display.

H.5. Excluding a Person with a certain tag from displayed list

First variation of excluding a person while all persons are listed
1. Prerequisites: List all persons using the list command.
2. Test case: find \tag \exclude neighbours
  Expected: All contacts with the tag neighbours is removed from the displayed list. Tag Keywords History with '-neighbours' message is shown in the results display
3. Test case: find \tag \exclude
  Expected: Invalid Command Format. Error details shown in results display.
Second variation of excluding a person while all persons are listed
1. Prerequisites: List all persons using the list command.
2. Test case: find \exclude \tag classmates
  Expected: All contacts with the tag classmates is removed from the displayed list. Tag Keywords History with '-classmates' message is shown in the results display
3. Test case: find \exclude \tag
  Expected: Invalid Command Format. Error details shown in results display.

H.6. UndoFind command

UndoFind Command with an Empty Search History.
1. Prerequisites: List all persons using the list command. Multiple persons in the list. This should clear the Search History stored internally within the application at the same time.
2. Test case: undofind
  Expected: Result Display shows "SearchHistory is Empty" message.
UndoFind Command with an Non-Empty Search History.
1. Prerequisites: List all persons using the list command. Multiple persons in the list, and then find \exclude Alex to execute the first search.
2. Test case: undofind
  Expected:
  All persons with the name Alex(case-insensitive) will be added back to the displayed list "Undo success!" message should shown in result display.

H.7. Search Pruning Feature

Prerequisites: List all persons using the list command. Multiple persons in the list.
1. Test case: find \tag friends and then find \tag colleagues+ Expected:
  After execution of first command
  All contacts with the tag friends is shown in the displayed list. Tag Keywords History with '+friends' is shown in the results display.
  After execution of second command
  All contacts that has both of the tag friends and colleagues is shown in the displayed list. Tag Keywords History with '+colleagues +friends' message is shown in the results display.

H.8. Deleting a person

Deleting a person while all persons are listed
1. Prerequisites: List all persons using the list command. Multiple persons in the list.
2. Test case: delete 1
  Expected: First contact is deleted from the list. Details of the deleted contact shown in the status message. Timestamp in the status bar is updated.
3. Test case: delete 0
  Expected: No person is deleted. Error details shown in the status message. Status bar remains the same.
4. Other incorrect delete commands to try: delete, delete x (where x is larger than the list size) {give more}
  Expected: Similar to previous.

H.9. Submitting budget calculation data

Submitting budget calculation data using the budget command
1. Prerequisites: Need to be logged in with member role.
2. Test case: budget c/Computing Club t/200 e/5
  Expected: A new club budget elements object is created with the input specified by the user. A successful creation of club budget elements message is shown in the results display.
3. Test case: budget c/Computing Club t/300 e/7
  Expected: A new club budget elements object is not created because a club budget elements object with club name as 'Computing Club' already exists after the execution of the test case above. Since club names entered by the user have to be a unique the command is not executed.
4. Other incorrect budget commands to try: budget, budget c/Comput!ng Club t/200 e/5, budget c Computing Club t/200 e/5, budget c/Computing t/200.0 e/5, budget c/Computing t/200 e/five
  Expected: similar to the previous test case.

H.10. Calculating and allocating final budgets to all the clubs

Calculating and allocating budgets to all the clubs using the calculatebudget command
1. Prerequisites: Need to be logged in with treasurer role, at least one club’s budget calculation data needs to have been submitted, and calculatebudget command must not have been used previously.
2. Test case: calculatebudget b/50000
  Expected: The budgets for all the clubs in the NUSSU-Connect memory are calculated and allocated
3. Test case: calculatebudget b/10000
  Expected: The budgeets will not be recalculated after having been calculated once already in the previous test case.
4. Other incorrect calculatebudget commands to try: calculatebudget, calculatebudget b 50000, calculatebudget 50000`, calculatebudget b/fifty, calculatebudget b/50000 when no budget calculation data has yet been submitted, etc. Expected: similar to the previous test case.

H.11. Viewing the allocated budget of a club

Viewing the allocated budget of a club using the viewbudget command
1. Prerequisites: Need to be logged in with either member, treasurer or president role, and the budgets need to already have been calculated (i.e. calculatebudget command needs to have been used)
2. Test case: viewbudget c/Computing Club
  Expected: The budget allocated to the 'Computing Club' will be shown to the user.
3. Test case: viewbudget c/Music (where the budget calculation data for the club 'Music' had not been submitted) Expected: The budget for the club 'Music' will not be found and an error message will be shown to the user.
4. Other incorrect viewbudget commands to try: viewbudget, viewbudget c Computing Club, viewbudget Computing Club, etc.

H.12. Saving data

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

NUSSU Connect - Developer Guide

Events-Driven nature of the design

Logic component

Model component

Ui component

Storage component

Use case: Delete person

`Logic` component

`Model` component

`Ui` component

`Storage` component