iContacts - Developer Guide

By: Team W14-B1 Since: Jun 2016 Licence: MIT

1. Introduction
2. Setting up
3. Design
4. Implementation
5. Documentation
6. Testing
7. Dev Ops
Appendix A: Suggested Programming Tasks to Get Started
- A.1. Improving each component
- A.2. Creating a new command: remark
Appendix B: Target Users
Appendix C: User Stories
Appendix D: Use Cases
Appendix E: Non Functional Requirements
Appendix F: Glossary

1. Introduction

iContacts is an address book application whose target audience is university students. iContacts aim to help students manage their contacts effectively and efficiently, as well as providing many other features such as setting reminders, tagging of contacts, emailing and more. This guide provides information for those who wish to join our team as either a developer or tester, and is intended to help you quickly understand the internal design of the application so that you will be able to understand how this application work. The guide also explains in detail the implementation of noteworthy features, as well as the testing methods used in developing iContacts.

2. Setting up

This section will guide you on how to set up the development environment for coding.

2.1. Prerequisites

JDK 1.8.0_60 or later

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

2.2. 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 the resources required by the application and tests.

2.3. Verifying the setup

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

2.4. Configurations to do before writing code

The following configurations need to be done before a developer starts writing the code. This is done to ensure that the java coding styles and practices are followed.

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. Here are the steps to rectify the order:

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.

2.4.2. Updating documentation to match your fork

After forking the repo, the links in the documentation will still point to the se-edu/addressbook-level4 repo. If you plan to develop this as a separate product (i.e. instead of contributing to the se-edu/addressbook-level4) , you should replace the URL in the variable 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.

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)

2.4.4. Getting started with coding

When you are ready to start coding, get some sense of the overall design by reading the Architecture section below:

3. Design

This section will explain the design aspects of iContacts.

3.1. Architecture

Figure 1 : Architecture Diagram

The Architecture Diagram given above (Refer to Figure 1) explains the high-level design of iContacts.

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.

Below is a quick overview of each component:

Main has only one class called MainApp, and it does the following:
- 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 the components to communicate with other components using events (i.e. a form of Event Driven design).
- LogsCenter : This class is used by many classes to write log messages to iContacts' log file.
The rest of iContacts consists of four components:
- UI : This is the UI of iContacts.
- Logic : This is the command executor.
- Model : This holds the data of the App in-memory.
- Storage : This 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 (Refer to Figure 2) defines its API in the Logic.java interface and exposes its functionality using the LogicManager.java class.

Figure 2 : Class Diagram of the Logic component

3.2. Events-Driven nature of the design

The Sequence Diagram below (Refer to Figure 3) 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 an AddressBookChangedEvent when the address book data are changed, instead of asking the Storage to save the updates to the hard disk.

The diagram below (Refer to Figure 4) 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 the 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.

3.3. Components

This section explains the UI, Logic, Model and Storage component used in iContacts.

3.3.1. UI component

The UI component provides the API of Graphical User Interface. The figure below (Refer to Figure 5) shows the structure of the 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 of these, including the MainWindow, inherit from the abstract UiPart class.

The UI component uses JavaFx UI framework. The layout of these UI parts is 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 the user commands using the Logic component.
binds itself to some data in the Model so that the UI can auto-update when the data in the Model changes.
responds to events raised from various parts of iContacts and updates the UI accordingly.

3.3.2. Logic component

The Logic component deals with how each command and its parser would be executed in an event-driven design. The figures below (Refer to Figures 6, 7) shows the structure of the Logic component.

Figure 6 : Structure of the Logic component

Figure 7 : Structure of Commands in the Logic component. This diagram shows finer details concerning XYZCommand and Command in Figure 6

API : Logic.java

The Logic component 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.

The figure below (Refer to Figure 8) shows the sequence diagram of interactions within the Logic component for the execute("delete 1") API call.

Figure 8 : Interactions inside the Logic component for the delete 1 command

3.3.3. Model component

The Model component handles the contacts in the address book and all its stored details in data structures which provide APIs to create, read, update and delete the contacts. The figure below (Refer to Figure 9) shows the structure of the Model component.

Figure 9 : Structure of the Model component

API : Model.java

The Model component

stores a UserPref object that represents the user’s preferences.
stores the address book data.
exposes an unmodifiable ObservableList<ReadOnlyPerson> 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 (UI, Logic and Storage).

3.3.4. Storage component

The Storage component handles the storage of all data of the address book in the local device. The figure below (Refer to Figure 10) shows the structure of the Storage component.

Figure 10 : 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.
can save the reminder data in xml format and read it back.

3.4. 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, as well as design considerations for some features.

4.1. Filter mechanism

The FilterCommand uses the NameAndTagsContainsKeywordsPredicate to filter the persons with matching name and/or tags. It accepts the List<String> nameKeywords and List<String> tagKeywords as parameters that are parsed by the FilterCommandParser. The code snippet below is the constructor for the class:

public class NameAndTagsContainsKeywordsPredicate {
    public NameAndTagsContainsKeywordsPredicate(List<String> nameKeywords, List<String> tagKeywords) {
        this.nameKeywords = nameKeywords;
        this.tagKeywords = tagKeywords;
    }
}

The method test(ReadOnlyPerson person) iterates through the nameKeywords and the tagKeywords to find a match of every person from the address book.

Below is an extract of the method test(ReadOnlyPerson person). The method countTagMatches(person) counts and returns the number of matches between the tags of the person and the tags in the tagKeywords. If the tagsMatchedCount is equal to the size of the tagKeywords, this means all the keywords in the tagKeywords match. The hasTag will then be set to true.

public class NameAndTagsContainsKeywordsPredicate {
    @Override
    public boolean test(ReadOnlyPerson person) {
        boolean hasTag = false;

        int numTagKeywords = tagKeywords.size();
        int tagsMatchedCount = 0;
        if (!tagKeywords.isEmpty()) {
            tagsMatchedCount = countTagMatches(person);
        }

        if (tagsMatchedCount == numTagKeywords) {
            hasTag = true;
        }
}

Below is an extract of the same method for name. Each keywords in the nameKeywords will be compared against the name list retrieved from the getName() method of the Person class. If all the keywords match, the hasName will be set to true.

public class NameAndTagsContainsKeywordsPredicate {
    @Override
    public boolean test(ReadOnlyPerson person) {
        boolean hasName = false;
            if (!nameKeywords.isEmpty()) {
                hasName = nameKeywords.stream().allMatch(nameKeywords -> StringUtil
                .containsWordIgnoreCase(person.getName().fullName, nameKeywords));
        }
    }
}

For the FilterCommand to work properly, either the nameKeywords or the tagKeywords must be non-empty.

Design Considerations

Aspect: Should similar search commands be separated
Alternative 1 (current choice): Create a separate command to search for contacts that match all keywords.
Pros: Users will not be confused between the functionality of the find and filter commands.
Cons: Users have to remember an additional command.
Alternative 2: Modify the FindCommand to allow users the option to search contacts that either match any keywords or match all keywords.
Pros: Lesser command for the users to remember when searching for contacts.
Cons: Implementation can be more complicated as there is a need to address both OR search and AND search on the same command.

4.2. Export mechanism

The ExportCommand uses XmlAddressBookStorage class to generate a xml file based on a given range and saves it to the path provided. It takes in two String values range and path. Below is the constructor for the class:

public class ExportCommand extends Command {
    public ExportCommand(String range, String path) {
        requireNonNull(range);
        requireNonNull(path);

        this.range = range;
        this.path = path;
        exportBook = new AddressBook();
    }
}

The method getRangefromInput() splits the range using a separator and returns a String array for the different values in the range.

Below is an extract of the method getRangefromInput():

public class ExportCommand extends Command {
    private String[] getRangeFromInput() {
        private String[] getRangeFromInput() {
            String[] splitStringComma = this.range.split(",");

            return splitStringComma;
        }
    }
}

To determine which contacts should be added to the exportBook we have to check the the user input. There are three cases:

All (Priority)
- if the word all is present in the user input, we will just export all the contacts from the last shown list.
Specific index (e.g. 1, 2, 3)
- if the user input contains a specific index, we will add that index (one-based) to the exportBook.
Range of indexes (e.g. 1-5,8-10)
- if the user input contains a range which is identified by the - character, we will add that range of index (one-based) to the exportBook.

Below is the code snippet to identify the three cases in the user input:

public class ExportCommand extends Command {

    @Override
    public CommandResult execute() throws CommandException {
        String[] multipleRange = getRangeFromInput();

        if (multipleRange[0].equals("all")) {
            exportAll();
        } else {
            for (int i = 0; i < multipleRange.length; i++) {
                if (multipleRange[i].contains("-")) {
                    String[] rangeToExport = multipleRange[i].split("-");
                    try {
                        exportRange(Integer.parseInt(rangeToExport[0]), Integer.parseInt(rangeToExport[1]));
                    } catch (NumberFormatException e) {
                        throw new CommandException(MESSAGE_EXPORT_FAIL);
                    }

                } else {
                    try {
                        exportSpecific(Integer.parseInt(multipleRange[i]));
                    } catch (NumberFormatException e) {
                        throw new CommandException(MESSAGE_EXPORT_FAIL);
                    }
                }
            }
        }
        /... storage is resolved here ...
    }
}

The final step is to create the xml file from the exportBook.

Below is the code snippet to export the data into an xml file using AddressBookStorage.

public class ExportCommand extends Command {
    @Override
    public CommandResult execute() throws CommandException {

    /... the exporting is resolved here ...

        try {
            AddressBookStorage storage = new XmlAddressBookStorage(path + ".xml");
            storage.saveAddressBook(exportBook);
        } catch (IOException ioe) {
            return new CommandResult(MESSAGE_EXPORT_FAIL);
        }
        return new CommandResult(MESSAGE_EXPORT_SUCCESS);
    }
}

4.3. Import mechanism

The ImportCommand uses XmlAddressBookStorage to generate a temporary AddressBook object from a given path. It takes in a String value path. The command then adds the contacts found in the temporary AddressBook object into the main address book object. Below is the constructor for the class:

public class ImportCommand extends UndoableCommand {
    public ImportCommand(String path) {
        this.path = path;
        this.addressBookStorage = new XmlAddressBookStorage(path);
        numSuccess = 0;
        numDuplicates = 0;
    }
}

The ImportCommand first checks if an AddressBook object can be initialised from the specified path, and if it does it initialises a new Person object and adds it into the main AddressBook object through the model. Below is the code snippet:

public class ImportCommand extends UndoableCommand {

    @Override
    public CommandResult executeUndoableCommand() throws CommandException {
        try {
            if (addressBookStorage.readAddressBook().isPresent()) {
                this.addressBook = new AddressBook(addressBookStorage.readAddressBook().get());
                for (ReadOnlyPerson person : this.addressBook.getPersonList()) {
                    Person personToAdd = new Person(person);
                    personToAdd.setPopularityCounter(new PopularityCounter());
                    personToAdd.setDisplayPicture(new DisplayPicture(""));
                    try {
                        model.clearSelection();
                        model.showDefaultPanel();
                        model.addPerson(personToAdd);
                        numSuccess++;
                    } catch (DuplicatePersonException e) {
                        numDuplicates++;
                    }
                }
            } else {
                throw new CommandException(String.format(MESSAGE_INVALID_FILE, path));
            }
        } catch (DataConversionException | IOException e) {
            throw new CommandException(String.format(MESSAGE_INVALID_FILE, path));
        }

        return new CommandResult(String.format(MESSAGE_SUCCESS, numSuccess, numDuplicates));
    }
}

Design Considerations

Aspect: Should PopularityCounter and DisplayPicture be set to the default value
Alternative 1 (current choice): Both PopularityCounter and DisplayPicture should be set to the default value.
Pros: Does not affect the contact’s PopularityCounter and allows the user to set their own preferred DisplayPicture of a contact.
Cons: Users will not be able to share DisplayPicture. Alternative 2: Import the contacts with both `PopularityCounter and DisplayPicture unchanged.
Pros: DisplayPicture will be imported into iContacts.
Cons: The PopularityCounter of the user’s contacts will be inaccurate.

4.4. Find mechanism

The FindCommand uses NameContainsKeywordsPredicate to find contacts with matching names or nicknames. It accepts List<String> nameKeywords as the parameter that is parsed by FindCommandParser. Below is the constructor for the class:

public FindCommand(NameContainsKeywordsPredicate predicate) {
        this.predicate = predicate;
    }

The method test(ReadOnlyPerson person) iterates through nameKeywords to find a match with the name or nickname of every person from the address book.

Below is an extract of the method test(ReadOnlyPerson person.

   @Override
    public boolean test(ReadOnlyPerson person) {
        return keywords.stream()
                .anyMatch(keyword -> StringUtil.containsWordIgnoreCase(person.getName().fullName, keyword))
                || keywords.stream()
                .anyMatch(keyword -> StringUtil.containsWordIgnoreCase(person.getNickname().value, keyword));
    }

For the FindCommand to work properly nameKeywords must be non-empty. The code extract below checks for empty inputs:

    public FindCommand parse(String args) throws ParseException {
        String trimmedArgs = args.trim();
        if (trimmedArgs.isEmpty()) {
            throw new ParseException(
                    String.format(MESSAGE_INVALID_COMMAND_FORMAT, FindCommand.MESSAGE_USAGE));
        }

        String[] nameKeywords = trimmedArgs.split("\\s+");

        return new FindCommand(new NameContainsKeywordsPredicate(Arrays.asList(nameKeywords)));
    }

4.5. Sorting mechanism

The SortCommand uses a SortedList that is initialised with the current filteredPerson and is sorted using a comparator. Below is the code snippet:

sortedfilteredPersons = new SortedList<>(filteredPersons);

@Override
public void sortFilteredPersonList() {

    Comparator<ReadOnlyPerson> sortByName = (o1, o2) -> o1.getName().fullName.compareTo(o2.getName().fullName);
    sortedfilteredPersons.setComparator(sortByName);
    indicateAddressBookChanged();
}

4.6. Undo/Redo mechanism

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

UndoRedoStack only deals with UndoableCommands. Commands that cannot be undone will inherit from Command instead. The following diagram (Refer to Figure 11) shows the inheritance diagram for commands:

Figure 11 : Inheritance diagram for commands

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

Commands that are not undoable are implemented this way:

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

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

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

        executeUndoableCommand();
    }
}

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

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

The user executes a new UndoableCommand, delete 5, to delete the 5th person in the address book. The current state of the address book is saved before the delete 5 command executes. The delete 5 command will then be pushed onto the undoStack (the current state is saved together with the command) (Refer to Figure 12).

Figure 12 : Stack diagram after executing Delete command

As the user continues to use the program, more commands are added into the undoStack. For example, the user may execute add n/David … to add a new person (Refer to Figure 13).

Figure 13 : Stack diagram after executing Add command

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

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

We will pop the most recent command out of the undoStack and push it back to the redoStack. We will restore the address book to the state before the add command executed (Refer to Figure 14).

Figure 14 : Stack diagram after executing Undo command

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

The following sequence diagram (Refer to Figure 15) shows how the undo operation works:

Figure 15 : Sequence diagram of the undo operation

The redo operation does the exact opposite (pops from redoStack, push to undoStack, and restores the address book to the state after the command is executed).

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

The user now decides to execute a new command, clear. As before, clear will be pushed into the undoStack. This time the redoStack is no longer empty. It will be purged as it no longer make sense to redo the add n/David command (this is the behavior that most modern desktop applications follow) (Refer to Figure 16).

Figure 16 : Stack diagram after executing Clear command

Commands that are not undoable are not added into the undoStack. For example, list, which inherits from Command rather than UndoableCommand, will not be added after execution (Refer to Figure 17):

Figure 17 : Stack diagram remains unchanged after executing List command

The following activity diagram (Refer to Figure 18) summarize what happens inside the UndoRedoStack when a user executes a new command:

Figure 18 : Activity diagram for UndoRedoStack

Design Considerations

Aspect: Implementation of UndoableCommand
Alternative 1 (current choice): Add a new abstract method executeUndoableCommand().
Pros: We will not lose any undone/redone functionality as it is now part of the default behaviour. Classes that deal with Command do not have to know that executeUndoableCommand() exist.
Cons: Will be hard for new developers to understand the template pattern.
Alternative 2: Just override execute().
Pros: It will not involve the template pattern, easier for new developers to understand.
Cons: Classes that inherit from UndoableCommand must remember to call super.execute(), or lose the ability to undo/redo.

Aspect: How undo & redo executes
Alternative 1 (current choice): Save the entire address book.
Pros: Will be 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: Care should be taken to ensure that the implementation of each individual command are correct.

Aspect: Type of commands that can be undone/redone
Alternative 1 (current choice): Only include commands that modifies the address book (add, clear, edit).
Pros: We only revert changes that are hard to change back (the view can easily be re-modified as no data are lost).
Cons: User might think that undo also applies when the list is modified (undoing filtering for example), only to realize that it does not do that, after executing undo.
Alternative 2: Include all commands.
Pros: Might be more intuitive for the user.
Cons: User have no way of skipping such commands if he or she just want to reset the state of the address book and not the view.
Additional Info: See our discussion here.

Aspect: Data structure to support the undo/redo commands
Alternative 1 (current choice): Use separate stack for undo and redo
Pros: Will make it easy to understand for new Computer Science student undergraduates, who are likely to be the new incoming developers of our project.
Cons: Logic is duplicated twice. For example, when a new command is executed, we must remember to update both HistoryManager and UndoRedoStack.
Alternative 2: Use HistoryManager for undo/redo
Pros: Won’t require the need to maintain a separate stack, and just reuse what is already in the codebase.
Cons: It will require 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.

4.7. Display Picture mechanism

The displaypic command adds or updates the display picture for the contact specified. The image is then displayed as ImageView in PersonCard and DetailsPanel. The arguments of the command are INDEX and PATHOFIMAGE. The image needs to be present in the local device of the user.

The Display Picture command is implemented in a way so that the image is read from the user specified path. It is then stored in iContacts directory so that the image is never lost.

By executing the given code below, a new folder named 'pictures/' is created if it is missing. The folder is used to store the images.

public void createPictureStorageFolder() throws IOException {
        requireNonNull(filePath);

        logger.info("Picture folder "  + filePath + " created if missing");
        File file  = new File(filePath);
        FileUtil.createIfMissing(file);
    }

Since the command has to read and write an image, the Storage architectural style is used and extended to Display pictures.

The following UML diagram shows the Storage Architecture for reading and writing of image file (Refer to Figure 19):

Figure 19 : UML Diagram for the extended Storage Component.

This command works by retrieving the image using BufferedImage. The command extracts the image from the specified absolute path of image e.g. C:\Users\Admin\Desktop\My files\pic.jpg

It then stores the image in the folder called /pictures/ present in the same directory as .jar by giving it a unique hashcode based on the user’s email address. The reading and writing of images is done using the ImageIO class.

An event handler is used to notify the UI and Storage component of the changes made in image and its name.

The sequence diagram for adding a display picture is shown below (Refer to Figure 20):

Figure 20 : Sequence Diagram for Display Picture Command.

The binder for refreshing the image every time the picture is updated is implemented by the following function:

public class PersonCard extends UiPart<Region> {
    private void assignImage(ReadOnlyPerson person) {

        Image image = new Image("file:" + "pictures/" + person.getDisplayPicture().getPath() + ".png",
                            IMAGE_WIDTH, IMAGE_HEIGHT, false, false);

        displayPicture.setFill(new ImagePattern(image));
    }
}

The Display Picture mechanism is done by using ImageView/ImagePattern in JavaFX which is a part of the UI Component. The Circle shape is used for better UI/UX design and is filled with the ImagePattern. The wireframe used to display the image for each person is shown below (Refer to Figure 21):

Figure 21 : Wireframe for the PersonCard.

The new image stored in directory is given a unique name which is formed using the hash code of the unique email address of each contact. The following code is used to set the name of image as the hash code:

public class DisplayPictureCommand extends Command {

    @Override
    public CommandResult execute() throws CommandException, IOException {
        /... executes function of Reading and Writing Image ...

        displayPicture.setPath(readAndStoreImage.execute(displayPicture.getPath(),
                            personToEdit.getEmail().hashCode())); // image name formed in this line
    }
}

Reason for this type of implementation

The command is implemented in this manner because of the following:

By specifying the index, there is no ambiguity as to who should be assigned the display picture.
The PATHOFIMAGE must be an absolute path on the local device to make sure the image is referenced.
The image is stored in directory with a unique name to avoid conflict. The hash code of the user’s email address is used to maintain uniqueness.
The task is done using CLI to follow project requirements.
The image is stored in png format to ensure maximum compatibility.
In case of image corruption/deletion, care is taken to avoid hanging of UI and display the default image. This is done by checking file.exists().

Design Considerations

Aspect: At what stage should the image be read and stored
Alternative 1 (current choice): Make proper Storage Architecture for reading and writing of Image.
Pros: It will follow the existing Architectural Design and Software Engineering Principles like OCP.
Cons: It will take more time and will be tougher to implement.
Alternative 2: Invoke 'ReadAndStoreImage' from Logic component.
Pros: : It will be easier for new developers to understand the sequence diagram and maintains event-driven nature.
Cons: It will cause bad architectural design and will not follow the pre-existing pattern and moreover will defy the Law of Demeter.

Aspect: How should the image be taken from user
Alternative 1 (current choice): User has to enter the absolute path of image by checking his local device.
Pros: It will be a complete CLI process.
Cons: It might be problematic for user to copy and paste and might result in error.
Alternative 2: Pop up a FileChooser after the command is entered.
Pros: It will be easier for users to mention the correct image quickly.
Cons: It will no longer be a complete CLI process.

4.8. Location mechanism

The location command is implemented in the form of an event-driven mechanism . The diagram below (Refer to Figure 22) shows the sequence diagram for the command execution:

Figure 22 : Sequence diagram for the Location Command.

The execution of command raises an event ShowLocationEvent. This causes the BrowserAndReminderPanel to switch to Node Browser irrespective of the current state of the application. The activity diagram for such case is shown below (Refer to Figure 23):

Figure 23 : Sequence diagram for the Location Command.

The following code below ensures the set up for the GUI:

private void setUpToShowLocation() {
    if (currentlyInFront == Node.REMINDERS) {
        setUpToShowBrowser();
        browser.toFront();
        currentlyInFront = Node.BROWSER;
    }
}

The URL for denoting the specified person’s address in Google Maps is set up through the following code:

public String loadPersonLocation(String address) {

        String[] splitAddressByWords = address.split("\\s");

        String keywordsOfUrl = "";

        for (String word: splitAddressByWords) {
            keywordsOfUrl += word;
            keywordsOfUrl += "+";
        }

        loadPage(GOOGLE_MAPS_URL + keywordsOfUrl);
}

Design Consideration

Aspect: What to use to show the location
Alternative 1 (current choice): Show using google maps url in BrowserPanel.
Pros: We will be able to get the location easily and accurately.
Cons: It could cause problem due to limited functionality of the URL.
Alternative 2: Use Google Maps API.
Pros: It will provide more functionality.
Cons: It could cause more resources to be used for the exact same feature and wouldn’t utilise pre-existing browser properly.

4.9. Email mechanism

The email command has various fields to denote the Recipients (Tag), Subject, Body and Service.

The email command allows the users to compose an email in the default browser with data such as recipients, subject and body.

The relation between them is shown in the UML diagram below (Refer to Figure 24):

Figure 24 : UML Class Diagram for the Email Feature.

The command is parsed to get the Service, Tag, Subject and Body fields.

The parsing takes place in the following manner (Refer to Figure 25):

Figure 25 : Sequence diagram for parsing the Email Command.

The recipients are all contacts belonging to a particular tag. The only two services offered are gmail and outlook as our target users are students.

The email command happens through an event driven mechanism. The below diagram (Refer to Figure 26) shows sequence diagram for it. The execution of command raises an event SendingEmailEvent.

Figure 26 : Sequence diagram for the Email Command.

The URL for composing the mail is set up through the following code:

public static final String GMAIL_EMAIL_URL =
            "https://mail.google.com/mail/?view=cm&fs=1&tf=1&source=mailto&to=%1$s&su=%2$s&body=%3$s";

public static final String OUTLOOK_EMAIL_URL =
            "https://outlook.office.com/?path=/mail/action/compose&to=%1$s&subject=%2$s&body=%3$s";

Desktop.getDesktop().browse(new URI(String.format(GMAIL_EMAIL_URL, recipients, subject, body)));

Design Consideration

Aspect: Where to compose the mail
Alternative 1 (current choice): Opens the default browser of Desktop.
Pros: The default browser will have the user logged in to his email account.
Cons: High dependency on third party apps.
Alternative 2: Open in BrowserPanel.
Pros: No dependency on other apps.
Cons: It will not auto fill in the text due to older version of browser.

4.10. Frequently Visited Contacts mechanism

This feature brings in a new UI element called PopularContactList, which is a list of maximum size of 5 and each element of showing the name, popularity rank and display picture in a PopularContactCard. The way these UI elements are added is shown in the following diagram (Refer to Figure 27) :

Figure 27 : Class Diagram of UI with Popular Contact Panel.

The mechanism to show the top five most frequently visited contacts is facilitated by the PopularityCounter of each contact. For every new person added into the address book, he is assigned a popularity counter of 0. The top five popular contacts are extracted by sorting the list based on the field PopularityCounter of each person. In the case of two or more people having the same popularity counter, the person who was added earlier into iContacts is given higher priority.

This feature is not implemented as a command.The list gets refreshed whenever the PopularityCounter is supposed to change.

The Frequently Visited Contacts mechanism is an event-driven mechanism. However, there is no explicit command to view the top five frequently visited contacts as they are always refreshed whenever there is an change in the address book. They are always displayed on the UI below the CommandResult panel. The event to refresh the PopularContactList, PopularContactChangedEvent is triggered whenever any of the command that increases PopularityCounter is executed.

The event triggers the following method:

public void updatePopularContactList() {
        refreshWithPopulatingAddressBook();
        listOfPersonsForPopularContacts.sort((o1, o2) ->
                o2.getPopularityCounter().getCounter() - o1.getPopularityCounter().getCounter());

        getOnlyTopFiveMaximum();
    }

The following are the commands which will increase the PopularityCounter by one for the contacts viewed or searched:

viewtag
select
details [special case when counter increases by 2 as it is a stronger indicator of who could be a frequently visited contact]
location
email

On execution of any of the following command, an extra event is raised which updates the PopularContactList after updating the popularity counter of the contact. The sequence diagram for the extra event is shown below for select command (Refer to Figure 28):

Figure 28 : Sequence diagram for frequently visited mechanism for select command.

Manual selection of person through a click also increases the popularity counter of that person. This is the same action as the details command.

The following method is used to increase the PopularityCounter by one:

public ReadOnlyPerson increaseCounterByOne(ReadOnlyPerson person) {
        person.getPopularityCounter().increasePopularityCounter();

        return new Person(person.getName(), person.getPhone(), person.getEmail(), person.getAddress(),
                person.getBirthday(), person.getNickname(), person.getDisplayPicture(), person.getPopularityCounter(),
                person.getTags());
    }

The sequence diagram below shows how the event is triggered and how the saving of updated address book takes place (Refer to Figure 29):

Figure 29 : Sequence diagram for frequently visited mechanism.

Design Considerations

Aspect: How to implement the feature
Alternative 1 (current choice): Refresh the list every time one of the command that changes the Popularity is executed
Pros: Becomes a dynamic feature such that user can see favourite contacts at any time
Cons: Makes application slightly slower as more execution of code for those commands
Alternative 2: Execute command to refresh list of popular contacts
Pros: Reduces regular refresh of list
Cons: Will have to keep track of command history to see the list of commands executed before previous execution of favourites command

4.11. Details Panel Implementation

The details command shows more details of the contact like address, birthday, email in addition to the details shown in the PersonCard of PersonListPanel

The DetailsPanel is an Anchor Pane which is embedded inside BrowserAndReminderPanel.

At any point of time, only one of the three panels (Browser, Reminder, Details) inside BrowserAndReminderPanel will have the visibility set as true and in front of the other two panels.

The UML diagram below represents the UI structure for the BrowserAndReminderPanel (Refer to Figure 30):

Figure 30 : UML Diagram for Panel.

The code to ensure only DetailsPanel is displayed on execution of command is shown below:

private void setUpToShowDetailsPanel() {
        detailsPanel.setVisible(true);
        remindersPanel.setVisible(false);
        browser.setVisible(false);
}

The DetailsPanel is also displayed when the user manually clicks on the PersonCard. This is made possible by raising the SelectionChangedEvent to show the DetailsPanel. The selectionModel() of PersonListView is now linked to the details command rather than the select command.

The select command now only scrolls to the INDEX specified whereas details command scrolls to and selects the person to show his/her details in the panel.

The figure below (Refer to figure 31) is the wireframe for the DetailsPanel:

Figure 31 : Wireframe for Details Panel.

Using the FontAwesomeFx library, an icon is set for each label to make the UI look appealing as seen in the UI above (Refer to figure TBD).

The solution to show the same colour for a tag in DetailsPanel and PersonCard was resolved by having a Singleton Class TagColor.

The following code inside the class ensured that the class acts as an global class and since only one instance is created, it made the tag color’s constant.

public static TagColor getInstance() {
        if (tagColor == null) {
            tagColor = new TagColor();
        }
        return tagColor;
    }

Design Consideration

Aspect: How to improve UI
Alternative 1 (current choice): Show the extra details of contact after they are selected.
Pros: Allows more contacts to be shown in the list as the information is reduced.
Cons: User needs to manually select the user to see more details of that person.
Alternative 2: Show all detail of person in the PersonCard.
Pros: Reduces effort of selection of contact to see extra details.
Cons: Looks very cluttered and has poor User Interface design.

4.12. View tag mechanism

The command is added into the Logic component according to following class diagram (Refer to Figure 32):

Figure 32 : Class Diagram of Logic.

The viewtag command works by setting the predicate to the Observable filteredlist.

Only one keyword is allowed for the command and it shows all people with the given tag.

The method test(ReadOnlyPerson person) iterates through the tagKeywords to find a match of every person from the address book.

Streams and lambda (Java 8 features) are used to make the code more readable as shown below:

public boolean test(ReadOnlyPerson person) {
        Set<Tag> tagsOfPerson = person.getTags();

        return tagsOfPerson.stream()
                .anyMatch(tagMatches -> tagMatches.getTagName().equalsIgnoreCase(keyword));

    }

Design Consideration

Aspect: How to filter the list
Alternative 1 (current choice): Use of Lambda and Stream.
Pros: The code is more readable.
Cons: It sometimes takes more time to process than normal loops.
Alternative 2: Loops and Conditions.
Pros: It is known to be faster than Streams at times.
Cons: It is harder to avoid arrow-headed violation of coding style.

4.13. Toggling mechanism

The toggling mechanism is an event-driven mechanism.

Figure 33 : Component interactions for the toggling mechanism.

The above diagram (Refer to Figure 33) shows the high-level overview of the component interactions for the toggling mechanism.

Figure 34 : Sequence diagram for the first part of the toggling mechanism.

As seen from the sequence diagram above (Refer to Figure 34), when the user types the command for toggle, an instance of ToggleCommand would be created.
Upon execution by LogicManager, the event BrowserAndRemindersPanelToggleEvent would be posted by the EventCenter to the EventBus:

public class ToggleCommand extends Command {
    @Override
    public CommandResult execute() {
        EventsCenter.getInstance().post(new BrowserAndRemindersPanelToggleEvent());
        // ... return some object or null ...
    }
}

As seen from the diagram below (Refer to Figure 35), the method handleBrowserToggleEvent() in the BrowserAndRemindersPanel class in the UI component will then listen for the event, and upon receiving the event it will invoke the method toggleBrowserPanel to trigger the actual toggling.

Figure 35 : Sequence diagram for the second part of the toggling mechanism.

The BrowserAndRemindersPanel class has a variable currentlyInFront keeping track of which panel (browser or reminders) is currently being shown. toggleBrowserPanel would then use the currentlyInFront variable to toggle to and show the correct panel, and then update currentlyInFront appropriately:

public class BrowserAndRemindersPanel extends UIPart<Region> {
    @Subscribe
    private void handleBrowserPanelToggleEvent(BrowserAndRemindersPanelToggleEvent event) {
        logger.info(LogsCenter.getEventHandlingLogMessage(event));
        toggleBrowserPanel();
    }

    private void toggleBrowserPanel() {
        switch(currentlyInFront) {
        case BROWSER:
            setUpToShowRemindersPanel();
            remindersPanel.toFront();
            currentlyInFront = Node.REMINDERS;
            break;
        case REMINDERS:
            setUpToShowWebBrowser();
            browser.toFront();
            currentlyInFront = Node.BROWSER;
            break;


        //... Other cases ...

        }
    }
}

One important thing to note is that when the select command is executed, the browser panel would be brought forward no matter what:

public class BrowserAndRemindersPanel extends UIPart<Region> {
    @Subscribe
    private void handleLoadPersonPageEvent(LoadPersonWebpageEvent event) {
        setUpToShowWebBrowser();
        currentlyInFront = Node.BROWSER;
        browser.toFront();
        loadPersonPage(event.getPerson());
    }

    private void setUpToShowWebBrowser() {
        browser.setVisible(true);
        detailsPanel.setVisible(false);
        remindersPanel.setVisible(false);
     }
}

The LoadPersonWebpageEvent is posted whenever the select command is executed. Within the handleLoadPersonPageEvent method, the statement browser.toFront() and the method setUpToShowWebBrowser would then bring the browser panel to the front no matter what, and also make it visible.

Design Considerations

Aspect: Usage of browser area
Alternative 1 (current choice): Allow users to toggle between the browser and reminders panel.
Pros: Can use the entire space for either the browser or reminders panel.
Cons: Users need to manually switch between the browser and reminders panel.
Alternative 2: Put reminders and browser panels side-by-side.
Pros: Users do not need to manually switch between the browser and reminders panel.
Cons: Too little space for browser and reminders, making it difficult to read for the users.

Aspect: Implementation of toggling mechanism.
Alternative 1 (current choice): Bring browser and reminders panel to the front as required, on top of setting their visibility suitably.
Pros: Users can interact with both browser and reminders (can scroll through reminders etc).
Cons: More difficult to implement.
Alternative 2: Only set visibility of browser and reminders panel as required (set browser visibility to false to display reminders and vice versa).
Pros: Easier to implement.
Cons: Users cannot interact with the reminders panel (since the browser is technically still at the front).

4.14. Reminder Implementation

Figure 36: UML class diagram showing the make-up of Reminder objects.

The Reminder object represents a reminder in iContacts. It contains a String variable reminder, which represents the actual reminder from the user, and also a Date, Time and Status object, which represents the date, time and status of the reminder respectively (Refer to Figure 36). As part of defensive programming, Reminder implements the ReadOnlyReminder interface, which only allows read operations, thus helping to prevent inappropriate or unintended modifications to Reminder objects (Refer to Figure 36) during the execution of the program. For example, for DeleteReminderCommand, its execute method should only execute the deletion of a specified reminder, not to alter any reminders. To ensure that no unintended or inappropriate alteration happens, DeleteReminderCommand is passed a list of ReadOnlyReminder instead of Reminder. This can be seen from the code snippet below:

public class DeleteReminderCommand extends Command {
    @Override
    public CommandResult execute() throws CommandException {
        List<ReadOnlyReminder> reminderListing = model.getSortedReminderList();

        if (targetIndex.getZeroBased() >= reminderListing.size()) {
            throw new CommandException(Messages.MESSAGE_INVALID_REMINDER_DISPLAYED_INDEX);
        }

        ReadOnlyReminder reminderToDelete = reminderListing.get(targetIndex.getZeroBased());

        try {
            model.deleteReminder(reminderToDelete);
        } catch (ReminderNotFoundException rnfe) {
            assert false : "The target reminder cannot be missing";
        }

        ... //return from method ...
    }
}

Figure 37: In-memory implementation of Reminder.

In terms of how Reminder objects are kept in-memory during the execution of the program, Reminder objects are kept within UniqueReminderList (Refer to Figure 37), which assures that there are no duplicate Reminder objects. The UniqueReminderList object is then kept and used by ModelManager to carry out commands related to reminders while the program is running.

Similar to Reminder, as can be seen from Figure 37 above, UniqueReminderList implements the ReadOnlyUniqueReminderList interface to prevent inappropriate or unintended modifications to UniqueReminderList during the execution of the program.

Figure 38: How Reminder is stored.

As seen from Figure 38, Reminder objects are stored in a XML storage file in a JAXB-friendly version XmlAdaptedReminder. Notably, the Status object is not stored along with the Reminder object; it is instantiated and initialized with an appropriate value during runtime when the Reminder object is instantiated. When the program starts, XmlAdaptedReminder objects are read in as XmlSerializableReminders via XmlFileStorage and XmlUtil. This can be seen below:

public class XmlFileStorage {

    public static XmlSerializableReminders loadRemindersFromSaveFile(File file) throws DataConversionException, FileNotFoundException {
        try{
            return XmlUtil.getDataFromFile(file, XmlSerializableReminders.class);
        } catch (JAXBException e) {
            throw new DataConversionException(e);
        }
    )

}

The XmlSerializableReminders object is then passed to UniqueReminderList, which then converts it into a list of Reminder objects for in-memory use. This can be seen below:

public class UniqueReminderList implements Iterable<Reminder>, ReadOnlyUniqueReminderList {
    public UniqueReminderList(ReadOnlyUniqueReminderList xmlReminders) {
        requireNonNull(xmlReminders);
        try {
            setReminders(xmlReminders.toModelType());
        } catch (DuplicateReminderException dre) {
            assert false : "Reminders from storage should not have duplicates";
        }
    }

    public void setReminders(List<ReadOnlyReminder> reminders) throws DuplicateReminderException {
        final UniqueReminderList replacement = new UniqueReminderList();
        for (final ReadOnlyReminder reminder : reminders) {
            replacement.add(new Reminder(reminder));
        }
        setReminders(replacement);
    }

    public void setReminders(UniqueReminderList replacement) {
        this.internalList.setAll(replacement.internalList);
    }
}

As can be seen from the code snippet above and in Figure 38, as part of defensive programming, XmlSerializableReminders also implements the ReadOnlyUniqueReminderList interface.

To save, the saveReminders method in StorageManager is invoked:

    @Override
    public void saveReminders(ReadOnlyUniqueReminderList reminderList) throws IOException {
        saveReminders(reminderList, remindersStorage.getRemindersFilePath());
    }

    @Override
    public void saveReminders(ReadOnlyUniqueReminderList reminderList, String filePath) throws IOException {
        logger.fine("Attempting to write to data file: " + filePath);
        remindersStorage.saveReminders(reminderList, filePath);
    }

This will then invoke the saveReminders method in XmlRemindersStorage, and go on to invoke the saveRemindersToFile method in XmlFileStorage, and finally the saveDataToFile method in XmlUtil.

The color of the reminder cells are decided and set during the formation of ReminderListViewCell. This can be seen from the code snippet below:

public class BirthdayAndReminderListPanel extends UiPart<Region> {

    class ReminderListViewCell extends ListCell<ReminderCard> {

        @Override
        protected void updateItem(ReminderCard reminder, boolean empty) {
            super.updateItem(reminder, empty);

            if (empty || reminder == null) {
                setGraphic(null);
                setText(null);
                return;
            }
            this.getStylesheets().clear();
            if (reminder.isEventToday()) {
                this.getStylesheets().add(REMINDER_TODAY_STYLE_SHEET);
            } else if (reminder.isEventWithinThreeDays()) {
                this.getStylesheets().add(REMINDER_THREE_DAYS_STYLE_SHEET);
            } else if (!reminder.hasEventPassed()) {
                this.getStylesheets().add(REMINDER_NORMAL_STYLE_SHEET);
            }

            setGraphic(reminder.getRoot());
        }
    }

}

Depending on the status of the reminder, different styles would be set for the specific ReminderListViewCell.

The methods isEventToday, isEventWithinThreeDays and hasEventPassed seen from the code snippet above originate from the Status object of each Reminder object and propagated from Status to Reminder then finally to ReminderCard.

Design Consideration

Aspect: How to store Reminder in-memory
Alternative 1 (current choice): Store Reminder objects in UniqueReminderList, independent of AddressBook.
Pros: Follows the Single-Responsibility Principle, because a reminder should not be an address book’s responsibility.
Cons: More changes have to be made to the existing code base, making it tougher to implement.
Alternative 2: Store Reminder objects within AddressBook.
Pros: Easier to implement as lesser changes have to be made to the existing code base.
Cons: Violates the Single-Responsibility Principle.

Aspect: Should the undo/redo mechanism be applied to Reminder
Alternative 1 (current choice): Commands that affect Reminder objects are not undoable/redoable.
Pros: Users would be more aware of any changes they made to a reminder, as they are forced to use the editreminder, addreminder and deletereminder commands.
Cons: It is less user-friendly.
Alternative 2: Commands that affect Reminder objects are undoable/redoable.
Pros: More user-friendly.
Cons: Users might get careless with changing the information of a Reminder object. This might be detrimental as the date and time fields of a Reminder are very important.

4.15. Theme-changing mechanism

Figure 39 : Component interactions for the theme-changing mechanism

The theme-changing mechanism is an event-driven mechanism. The above diagram (Refer to Figure 39) shows the high-level overview of the component interactions for the theme-changing mechanism.

Figure 40 : Sequence diagram for the first part of the theme-changing mechanism

As shown from the sequence diagram above (Refer to Figure 40), after the user entered the command theme day, a new object ThemeCommand will be created. The LogicManager will then execute ThemeCommand, and the event ChangeThemeRequestEvent will be posted by EventsCenter. The code snippet below shows the execute() method of ThemeCommand:

public class ThemeCommand extends Command {
    @Override
    public CommandResult execute() {
        EventsCenter.getInstance().post(new ChangeThemeRequestEvent(theme));
        return new CommandResult(String.format(MESSAGE_SET_THEME_SUCCESS, theme.getTheme()));
    }
}

Figure 41 : Sequence diagram for the second part of the theme-changing mechanism

As shown from the sequence diagram above (Refer to Figure 41), the method handleChangeThemeEvent() in MainWindow will handle the event and change the theme of the address book through the method changeTheme() accordingly.

Design Considerations

Aspect: Implementation of ThemeCommand
Alternative 1 (current choice): Utilize ChangeEventRequestEvent that allow MainWindow to handle the event to change the theme.
Pros: ThemeCommand can be more efficient since it does not directly change the theme.
Cons: New developers may find it difficult to understand the event-driven nature of the application.
Alternative 2: Allow ThemeCommand to set the theme directly by allowing it access to MainWindow.
Pros: Easier for new developers to understand.
Cons: Violates the architectural style as ThemeCommand belongs to the Logic component that should not be able to access the UI component where MainWindow belongs to.

4.16. 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 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

The list below shows all the available logging levels used:

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.

4.17. Configuration

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

5. 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.

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.

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 (Refer to Figure 42).

Figure 42 : Saving documentation as PDF files in Chrome

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).

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:

GUI Tests - These are tests involving the GUI. They include
- System Tests that test the entire App by simulating user actions on the GUI. These are in the systemtests package.
- 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
- Unit tests targeting the lowest level methods/classes.
  e.g. seedu.address.commons.StringUtilTest
- 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
- Hybrids of unit and integration tests. These tests are checking multiple code units as well as how they are connected together.
  e.g. seedu.address.logic.LogicManagerTest

6.3. Troubleshooting Testing

Problem: HelpWindowTest fails with a NullPointerException.

Reason: One of its dependencies, UserGuide.html in src/main/resources/docs is missing.
Solution: Execute Gradle task processResources.

7. Dev Ops

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. 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.

7.4. Managing Dependencies

A project often depends on third-party libraries. For example, iContacts 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:

Include those libraries in the repo (this bloats the repo size).
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 this section Improving a Component.
Next, add a feature that touches multiple components to learn how to implement an end-to-end feature across all components. The section 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

Do take a look at the Design: Logic Component section 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.
  
  See this PR for the full solution.

`Model` component

Do take a look at the Design: Model Component section 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 API needs to be updated.
  
  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
  
  Add the implementation of deleteTag(Tag) method in ModelManager. Loop through each person, and remove the tag from each person.
  
  See this PR for the full solution.

`Ui` component

Do take a look at the Design: UI Component section before attempting to modify the UI component.

Use different colors for different tags inside person cards. For example, friends tags can be all in grey, and colleagues tags can be all in red (Refer to Figures 43 and 44).

Before

Figure 43: Before applying colors to tags.

After

Figure 44: After applying colors to tags.
- Hints
  
  The tag labels are created inside PersonCard#initTags(ReadOnlyPerson) (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.
- Solution
  
  See this PR for the full solution.
Modify NewResultAvailableEvent such that ResultDisplay can show a different style on error (currently it shows the same regardless of errors) (Refer to Figures 45 and 46).

Before

Figure 45: Style before modification.

After

Figure 46: Style after modification.
- 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(event) to react to this event appropriately.
  
  See this PR for the full solution.
Modify the StatusBarFooter to show the total number of people in the address book (Refer to Figures 47 and 48).

Before

Figure 47: No values showed before modification.

After

Figure 48: Number of persons showed after modification.
- 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.
  
  See this PR for the full solution.

`Storage` component

Do take a look at the Design: Storage Component section 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 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.

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 UndoableCommand. Upon execution, it should just throw an Exception.
Modify AddressBookParser to accept a RemarkCommand.

Tests:

Add RemarkCommandTest that tests that executeUndoableCommand() 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 ReadOnlyPerson 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 `ReadOnlyPerson` to support a `Remark` field

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

Main:

Add three methods setRemark(Remark), getRemark() and remarkProperty(). Be sure to implement these newly created methods in Person, which implements the ReadOnlyPerson interface.
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.
Be sure to modify the logic of the constructor and toModelType(), which handles the conversion to/from ReadOnlyPerson.

Tests:

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

[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#bindListeners() to add the binding for remark.

Tests:

Modify GuiTestAssert#assertCardDisplaysPerson(…) so that it will compare the remark label.
In PersonCardTest, call personWithTags.setRemark(ALICE.getRemark()) to test that changes in the Person 's remark correctly updates the corresponding PersonCard.

[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: Target Users

This application is targeted towards University students, aiming to meet their needs throughout their university life, and hopefully beyond. University students meet many people in the university, such as project group members, tutors, lecturers, friends and other connections. Nowadays it is important for students to build connections with other people, as connections may also help students for their future career after graduation. Since the students meet a lot of people, they may not be able to remember all the information about the people they met. Therefore, iContacts aims to help students to store and manage their contacts easily.

User Profile
- University Students
- Students who are part of many CCA clubs and committees
- Students taking on the role of Teaching Assistant/Tutor
- Students who are interning and have colleagues
- Students who have close friends and family

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…
`* * *`	busy user	search using accumulative attributes	narrow down my search in the shortest time possible
`* * *`	careless user that finds it troublesome to follow a particular order of entering contact information	add contact information without following any particular order	enter contact information more easily and conveniently
`* * *`	forgetful user that can’t remember all tags	view a list of existing tags	recall and reuse the tags associated with a person
`* * *`	organized user	search for contacts by a given tag	get the list of contacts with the same tag
`* * *`	sociable user that was given contacts by another person	import from another source file	add contacts that were shared with me
`* * *`	sociable student	export selected contacts	share my contacts with friends
`* * *`	sociable user	store the person’s birthday	keep track of the person’s birthday
`* * *`	user	sort the list by name alphabetically	view contacts in an alphabetical order
`* * *`	user with limited details of a contact like name and phone number	add user with just the name and phone number	store contact information with limited detail
`* * *`	student with large number of connections	identify tags by colors and their alphabetical order	easily identify different tags and their alphabetical order in the GUI
`* * *`	user visiting a friend	view a person’s address location in Google Maps in the GUI	find directions to his/her place
`* * *`	user	search for contacts with just the first few characters of their name	find contacts if I’m unable to remember the spelling of the name
`* * *`	forgetful user	add nicknames for people	easily search for them
`* * *`	new user	see usage instructions	refer to instructions when I forget how to use the App
`* * *`	user	add a new person	to populate data in the address book
`* * *`	user	delete a person	remove entries that I no longer need
`* * *`	user	find a person by name	locate details of persons without having to go through the entire list
`* * *`	forgetful user	be able to make changes to existing information when I edit a person’s contact information instead of retyping it	refer to what was previously entered under a person’s contact information and make changes more easily
`* *`	user	hide private contact details by default	minimize chance of someone else seeing them by accident
`* *`	user	find my frequently used contacts at the top of the displayed list when I do a search	quickly find the contact information I need
`* *`	regular user	see frequently used contacts instantly	locate them more easily
`* *`	user	be able to add Display Picture for my contacts	easily identify them
`* *`	student who doesn’t use his laptop everywhere	view my address book online	view it without the device running the software
`* *`	member of a team	send email to a group of persons with one command	easily send email to a group of persons
`* *`	user	include more details for a person’s contact information	store more information about a person to identify him/her more easily
`* *`	user	delete multiple persons in one command	remove several persons that I no longer need quickly
`* *`	young student who likes user-friendly applications	have color-coded commands and contact information in command line	identify the command and contact information easily
`* *`	lazy user	auto-completion of commands	use the address book more conveniently
`* *`	trendy user	choose my own theme for the address book	customise the address book to my own liking
`* *`	user	view my recent additions	identify which person is newly added
`* *`	frequent user	change the font of the address book	protect my eyes
`* *`	expert user	define my own short-hand aliases for commands	personalise the address book to suit my needs
`* *`	lazy user	have short-hand form for each command	perform commands quickly
`* *`	busy student	set reminders	remind myself of any activities or events that will happen
`* *`	careless student	save the address book as an external file	backup or transfer the address book easily
`* *`	user	add multiple emails and phone numbers to a person	handle persons with more than one email and phone numbers
`* *`	student with many friends	get reminder of any approaching birthday	prepare for the person’s birthday
`* *`	user	sort persons by birthday	identify the persons who will have a birthday soon
`*`	careless user	search a person using similar keywords	find contacts if I do not know the correct spelling
`*`	student with many connections	add same tag(s) to multiple persons in one command	tag multiple persons quickly
`*`	organized student	auto sort the list whenever I add a person	avoid using the sort command with every single additions
`*`	busy student with many commitments	be able to create meeting reminders with my contacts	prevent myself from forgetting whom should I be meeting at what time
`*`	user	have a secured address book	have access to my address book

* * *

busy user

search using accumulative attributes

narrow down my search in the shortest time possible

* * *

careless user that finds it troublesome to follow a particular order of entering contact information

add contact information without following any particular order

enter contact information more easily and conveniently

* * *

forgetful user that can’t remember all tags

view a list of existing tags

recall and reuse the tags associated with a person

* * *

organized user

search for contacts by a given tag

get the list of contacts with the same tag

* * *

sociable user that was given contacts by another person

import from another source file

add contacts that were shared with me

* * *

sociable student

export selected contacts

share my contacts with friends

* * *

sociable user

store the person’s birthday

keep track of the person’s birthday

* * *

user

sort the list by name alphabetically

view contacts in an alphabetical order

* * *

user with limited details of a contact like name and phone number

add user with just the name and phone number

store contact information with limited detail

* * *

student with large number of connections

identify tags by colors and their alphabetical order

easily identify different tags and their alphabetical order in the GUI

* * *

user visiting a friend

view a person’s address location in Google Maps in the GUI

find directions to his/her place

* * *

user

search for contacts with just the first few characters of their name

find contacts if I’m unable to remember the spelling of the name

* * *

forgetful user

add nicknames for people

easily search for them

* * *

new user

see usage instructions

refer to instructions when I forget how to use the App

* * *

user

add a new person

to populate data in the address book

* * *

user

delete a person

remove entries that I no longer need

* * *

user

find a person by name

locate details of persons without having to go through the entire list

* * *

forgetful user

be able to make changes to existing information when I edit a person’s contact information instead of retyping it

refer to what was previously entered under a person’s contact information and make changes more easily

* *

user

hide private contact details by default

minimize chance of someone else seeing them by accident

* *

user

find my frequently used contacts at the top of the displayed list when I do a search

quickly find the contact information I need

* *

regular user

see frequently used contacts instantly

locate them more easily

* *

user

be able to add Display Picture for my contacts

easily identify them

* *

student who doesn’t use his laptop everywhere

view my address book online

view it without the device running the software

* *

member of a team

send email to a group of persons with one command

easily send email to a group of persons

* *

user

include more details for a person’s contact information

store more information about a person to identify him/her more easily

* *

user

delete multiple persons in one command

remove several persons that I no longer need quickly

* *

young student who likes user-friendly applications

have color-coded commands and contact information in command line

identify the command and contact information easily

* *

lazy user

auto-completion of commands

use the address book more conveniently

* *

trendy user

choose my own theme for the address book

customise the address book to my own liking

* *

user

view my recent additions

identify which person is newly added

* *

frequent user

change the font of the address book

protect my eyes

* *

expert user

define my own short-hand aliases for commands

personalise the address book to suit my needs

* *

lazy user

have short-hand form for each command

perform commands quickly

* *

busy student

set reminders

remind myself of any activities or events that will happen

* *

careless student

save the address book as an external file

backup or transfer the address book easily

* *

user

add multiple emails and phone numbers to a person

handle persons with more than one email and phone numbers

* *

student with many friends

get reminder of any approaching birthday

prepare for the person’s birthday

* *

user

sort persons by birthday

identify the persons who will have a birthday soon

*

careless user

search a person using similar keywords

find contacts if I do not know the correct spelling

*

student with many connections

add same tag(s) to multiple persons in one command

tag multiple persons quickly

*

organized student

auto sort the list whenever I add a person

avoid using the sort command with every single additions

*

busy student with many commitments

be able to create meeting reminders with my contacts

prevent myself from forgetting whom should I be meeting at what time

*

user

have a secured address book

have access to my address book

Appendix D: Use Cases

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

Use case: UC1 - Delete person

MSS

User requests to list persons
iContacts shows a list of persons
User requests to delete a specific person in the list
iContacts deletes the person

Use case ends.

Extensions

2a. The list is empty.

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

Use case: UC2 - Export Contacts

MSS

User selects contacts to be exported based on current list
iContacts takes note of the selected contacts and processes them
User requests for creating file containing selected contacts
iContacts creates file with the contact information of specified contacts
User specifies the location where data file needs to be stored
iContacts saves the data file in proper format and indicates success
User sends the data file to the required recipient

Use case ends.

Extensions

1a. No contacts selected

Use case ends.
3a. iContacts unable to create file with mentioned contacts
- 3a1. iContacts shows an error message.
  
  Use case resumes at step 1.
5a. iContacts unable to store at given location
- 5a1. iContacts shows an error message.
  
  Use case ends
*a. At any time user chooses to cancel exporting contacts
- *a1. iContacts shows an error message.
  
  Use case ends.

Use case: UC3 - Import Contacts

Precondition

User receives the data file containing contacts

MSS

User requests to import contacts
iContacts requests for file location
User specifies location where the data file is found
iContacts reads the file and merges the contacts from the received data file into the data file that iContacts is currently using

Use case ends.

Extensions

3a. No file selected

Use case ends.
4a. iContacts finds duplicate contacts
- 4a1. iContacts shows an error message and doesn’t merge the contacts which are duplicate
  
  Use case resumes at step 1.

4b. iContacts unable to locate the path of file and open it
- 4b1. iContacts shows an error message.
  
  Use case ends
*a. At any time user chooses to cancel importing contacts
- *a1. iContacts shows an error message.
  
  Use case ends.

Guarantees

The sharing is completed with recipient successfully being able to get the shared contacts

MSS

Sending User Exports Contacts (UC2)
Receiving User Imports Contacts (UC3)
Receiving User views the list of new contacts

Use case ends.

Use case: UC5 - List contacts after applying filtered search

MSS

User specifies the keywords for different attributes and requests the list
iContacts finds list of all people satisfying all attributes and displays them in a list

Use case ends.

Extensions

2a. The list is empty

Use case ends.

Use case: UC6 - Get directions to a contact’s address

MSS

User requests for the list of contacts
iContacts displays list of all such contacts
User requests for directions to a contact’s address
iContacts shows directions from current location to contact’s address in Google Maps using GUI

Use case ends.

Extensions

2a. The list is empty

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

4a. Google Maps unable to find location of direction to address
- 4a1. iContacts shows an error message through GUI
  
  Use case ends.

Appendix E: Non Functional Requirements

Should work on any mainstream OS as long as it has Java 1.8.0_60 or higher installed.
Should be able to hold up to 1000 persons without a noticeable sluggishness in performance for typical usage.
A user with above average typing speed for regular English text (i.e. not code, not system admin commands) should be able to accomplish most of the tasks faster using commands than using the mouse.
A new user to a CLI environment and/or address book application should be able to learn how to start and use the application within 20 minutes with the help of the User Guide.
Should be responsive and commands are executed within 2 seconds under normal load (1000 persons or less)
Essential services (adding, deleting contacts etc) should still work perfectly without Internet access.
The GUI should follow the The Java Look and Feel guidelines.
Should not consume more than 10% of the modern computers/laptop’s CPU’s processing time/power.
Should take up as little memory on the hard disk/permanent memory as possible, less than 100 MB.
Should be free to download and use.
Should work on 32-bit and 64-bit environments.
Should not display content not associated with the operations of the address book.
User Guide and Developer Guide should be well-documented.
Should be backwards compatible with storage files from prior versions.
Should be compatible with storage files from the same application but from different computers.
Should minimize dependencies on third-party software.
Project should not costs more than S$10,000.

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

Contact information of a person

Contact information of a person, including his/her name, phone, email, address and (optional) tags related to that person.

Attributes

Name and tags of a person

Frequently Used Contacts

The contact information of persons that are frequently viewed or selected.

Tag

A label attached to a person's contact information for the purpose of identification, grouping, and to give more information about that person.

Command Line Interface

A user interface to an application in which the users responds to a prompt by typing in a command on a specified line

Graphical User Interface

A user interface to an application in which the users interact with the application through graphical icons and visual indicators

The Java Look and Feel

It specifies the Java user interface components across a broad spectrum of Java based frameworks.

Data File

The XML file that stores the contact information of address book. This is also the file that iContacts reads from when starting up. There can be multiple data files at any one time.

Contacts

The people whose details are present in my address book.

Display Picture

A photo of the person represented by this contact entry

Google Maps

A web mapping service procided by Google that offers satellite imagery, street maps, route planning, real-time traffic conditions and other features.

Gradle

An open-source build automation system that also serve as a dependency management tool.

JavaFX

A software platform that contains a set of graphics and packages that enables developers to develop rich applications that can run across a wide variety of devices and platforms.

Travis

A hosted, distributed continuous integration service used to build and test software projects hosted at GitHub on a Linux virtual machine.

AppVeyor

A hosted, distributed integration service used to build and test software projects hosted at GitHub on a Microsoft Windows virtual machine.

Status

A description of the current state of the event, whether it has already passed, is happening now, is happening within three days or not happening anytime soon.

iContacts - Developer Guide

Design Considerations

Design Considerations

Design Considerations

Reason for this type of implementation

Design Considerations

Design Consideration

Design Consideration

Design Considerations

Design Consideration

Design Consideration

Design Considerations

Design Consideration

Design Considerations

Logic component

Model component

Ui component

Storage component

Use case: UC1 - Delete person

Use case: UC2 - Export Contacts

Use case: UC3 - Import Contacts

Use case: UC4 - Sharing Contacts

Use case: UC5 - List contacts after applying filtered search

Use case: UC6 - Get directions to a contact’s address

`Logic` component

`Model` component

`Ui` component

`Storage` component