Recruit Me - Developer Guide

1. Setting up

1.1. Prerequisites

JDK 9 (revision 1.9.4 or later). Only JDK 9 is supported.
This app will not work with later major JDK releases such as JDK 10, 11, etc.

If the tests are failing due to a system error with Java9, then try to run with Java8.

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

1.2. Setting up the project in your computer

Fork this repo, and clone the fork to your computer
Open IntelliJ (if you are not in the welcome screen, click File > Close Project to close the existing project dialog first)
Set up the correct JDK version for Gradle
1. Click Configure > Project Defaults > Project Structure
2. Click New… and find the directory of the JDK
Click Import Project
Locate the build.gradle file and select it. Click OK
Click Open as Project
Click OK to accept the default settings
Open a console and run the command gradlew processResources (Mac/Linux: ./gradlew processResources). It should finish with the BUILD SUCCESSFUL message.
This will generate all resources required by the application and tests.

1.3. Verifying the setup

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

1.4. Configurations to do before writing code

1.4.1. Configuring the coding style

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

Go to File > Settings… (Windows/Linux), or IntelliJ IDEA > Preferences… (macOS)
Select Editor > Code Style > Java
Click on the Imports tab to set the order
- For Class count to use import with '*' and Names count to use static import with '*': Set to 999 to prevent IntelliJ from contracting the import statements
- For Import Layout: The order is import static all other imports, import java.*, import javax.*, import org.*, import com.*, import all other imports. Add a <blank line> between each import

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

1.4.2. Updating documentation to match your fork

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

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

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

1.4.3. Setting up CI

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

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

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

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

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

1.4.4. Getting started with coding

When you are ready to start coding,

Get some sense of the overall design by reading Section 2.1, “Architecture”.
Take a look at [GetStartedProgramming].

2. Design

2.1. Architecture

Figure 1. Architecture Diagram

The Architecture Diagram given above explains the high-level design of the App. Given below is a quick overview of each component.

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

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

At app launch: Initializes the components in the correct sequence, and connects them up with each other.
At shut down: Shuts down the components and invokes cleanup method where necessary.

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

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

The rest of the App consists of four components.

UI: The UI of the App.
Logic: The command executor.
Model: Holds the data of the App in-memory.
Storage: Reads data from, and writes data to, the hard disk.

Each of the four components

Defines its API in an interface with the same name as the Component.
Exposes its functionality using a {Component Name}Manager class.

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

Figure 2. Class Diagram of the Logic Component

How the architecture components interact with each other

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

Figure 3. Component interactions for delete 1 command

The sections below give more details of each component.

2.2. UI component

Figure 4. Structure of the UI Component

API : Ui.java

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

The UI component uses JavaFx UI framework. The layout of these UI parts are defined in matching .fxml files that are in the src/main/resources/view folder. For example, the layout of the MainWindow is specified in MainWindow.fxml

The UI component,

Executes user commands using the Logic component.
Listens for changes to Model data so that the UI can be updated with the modified data.

2.3. Logic component

Figure 5. Structure of the Logic Component

API : Logic.java

Logic uses the AddressBookParser class to parse the user command.
This results in a Command object which is executed by the LogicManager.
The command execution can affect the Model (e.g. adding a person).
The result of the command execution is encapsulated as a CommandResult object which is passed back to the Ui.
In addition, the CommandResult object can also instruct the Ui to perform certain actions, such as displaying help to the user.

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

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

2.4. Model component

Figure 7. Structure of the Model Component

API : Model.java

The Model,

stores a UserPref object that represents the user’s preferences.
stores the Address Book data.
exposes an unmodifiable ObservableList<Person> that can be 'observed' e.g. the UI can be bound to this list so that the UI automatically updates when the data in the list change.
does not depend on any of the other three components.

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

2.5. Storage component

Figure 8. Structure of the Storage Component

API : Storage.java

The Storage component,

can save UserPref objects in json format and read it back.
can save the Address Book data in json format and read it back.

2.6. Common classes

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

3. Implementation

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

3.1. Undo/Redo feature

3.1.1. Current Implementation

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

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

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

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

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

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

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

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

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

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

The following sequence diagram shows how the undo operation works:

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

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

Step 5. The user then decides to execute the command list. Commands that do not modify the address book, such as list, will usually not call Model#commitAddressBook(), Model#undoAddressBook() or Model#redoAddressBook(). Thus, the addressBookStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitAddressBook(). Since the currentStatePointer is not pointing at the end of the addressBookStateList, all address book states after the currentStatePointer will be purged. We designed it this way because it no longer makes sense to redo the add n/David … command. This is the behavior that most modern desktop applications follow.

The following activity diagram summarizes what happens when a user executes a new command:

3.1.2. Design Considerations

Aspect: How undo & redo executes

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

Aspect: Data structure to support the undo/redo commands

Alternative 1 (current choice): Use a list to store the history of address book states.
- Pros: Easy for new Computer Science student undergraduates to understand, who are likely to be the new incoming developers of our project.
- Cons: Logic is duplicated twice. For example, when a new command is executed, we must remember to update both HistoryManager and VersionedAddressBook.
Alternative 2: Use HistoryManager for undo/redo
- Pros: We do not need to maintain a separate list, and just reuse what is already in the codebase.
- Cons: Requires dealing with commands that have already been undone: We must remember to skip these commands. Violates Single Responsibility Principle and Separation of Concerns as HistoryManager now needs to do two different things.

3.2. Colored Tag Feature

Color-coordinated tags that represent a candidate’s technical and professional skills, their position interests, and their endorsements created by members of the hiring company. Tags are a critical part of the recruitment platform in order to create a user-friendly, cohesive view of all candidates.Candidate tags are organized as pink for skills, yellow for positions of interest, and blue for employee endorsements.

3.2.1. Current Implementation

Add and Edit Commands

Tag colors are determined by user input prefixes 'skill' and 'position'

For example: add n/Amanda Collins …other attributes… skill/Java skill/Powerpoint position/Project Manager

Endorsement tags are separately determined by the endorse command and cannot be specified as part of a user profile in the add and edit commands.

These prefixes (skill and position) create new SkillsTag objects that specify the type of tag ('skill', 'pos', or 'endorse') which is stored as an attribute in the SkillsTag class.

The type attribute then specifies which tag color attribute is assigned to the SkillsTag, which is then communicated to the Storage component.

SkillsTag in Logic component communicates to the CSS file in the GUI to change the color.

The color attribute is then modeled as a JsonAdaptedTag in the Storage component.

IMPORTANT NOTE the current implementation works with the JSON Constructor by adding a prefix to each tagName attribute that represents what tag type the object is. The strings 's:', 'p:', and 'e:' are prepended to each respective skill, position, or endorse tag’s tagName attribute.

Other commands such as filtering and sorting are currently integrated with this design approach and parse out the prefixes to get the correct tag names. This design helps the filter and sort commands differentiate between the three tag types in order to properly display the results of their commands and improve user readability.

3.2.2. Alternate Implementation

Coming in v2.0

Logic Component Changes

Instead of representing tag type as an attribute of a SkillsTag object, a Tag interface will be implemented by distinct SkillsTag, PositionTag, EndorseTag objects.
The tags will have separate adapted JSON objects in order to correctly store the colors in the Storage component.
This will replace the current system of prepending tagName attributes with the respective tag type prefixes ('s:', 'p:', and 'e:').

UI Component Changes

While the current implementation makes UI changes in the colors of the tags, the next implementation will have the separate tags featured on different lines instead of the current List of tags that has them in a random order.
The new view will improve the UI design to make the tags more organized and clear.

3.3. Filter or/and/clear/reverse feature

Usage Format Regarding Current Implementation:

Format 1: filter or/and [name<NAME>name] [phone<PHONE>phone] [email<EMAIL>email] [gpa<GPA>gpa] [edu<EDUCATION>edu] [deg<DEGREE-LEVEL>deg] [addr<ADDRESS>addr] [skill<SKILL1, SKILL2, … >skill][pos<POSITION1, POSITION2, … >pos] [end<ENDORSEMENT-COUNT>end]
Format 2: filter clear/reverse

Basic Definitions Before the Actual Implementation Explanation:

PREFIX: For every single field (name, phone, email etc.), the leading combination of characters which indicate that the data for that field will be entered beginning from that location of the input.
- e.g. for name field name<, for gpa field gpa<
REVERSE PREFIX: For every single field, the combination of terminating characters which indicate that the data for that field will be stopped after that location of the input.
- e.g. for email field >email`, for skills field >skill
CRITERIA/CRITERION: These are the texts that are between 'PREFIX' and 'REVERSE PREFIX'
- e.g. for the input filter and deg<bachelors>deg phone<95>phone, the criterion are bachelors and 95.
- all the criterion possible for filtering are: NAME, PHONE, EMAIL, GPA, EDUCATION, DEGREE-LEVEL, ADDRESS, SKILLS (It can have multiple criterion inside of it, e.g. skill<C, Java>skill has 2 criterion C and Java), POSITIONS (same situation with SKILLS), ENDORSEMENT-COUNT.

Differences of 4 Types of Filter Commands:

AND: This type of command is used for only showing the persons that passes all the criterion given in the input.
- e.g. if input is filter and edu<NUS>edu pos<Manager, Developer>pos, only the persons, who have studied in NUS and applied for both Manager and Developer positions, will be shown.
OR: This type of command is used for only showing the persons that passes at least one of the criterion given in the input.
- e.g. if input is filter or addr<Singapore>addr skill<C, Java>skill, only the persons who live in Singapore or knows about the skills that contain C or Java will be shown
CLEAR: If a filtering is applied before and the currently viewed list is a filtered list of persons, then this type clears all the active filtering and shows all the persons in the storage.
REVERSE: If a filtering is applied before, this command shows only the persons that are eliminated with the previous filtering conditions. Basically, it reverses the filter.
- e.g. if input is filter reverse and if there are 11 persons in the total storage but only 7 are shown since there is a filtering, this type shows only the 4 other persons that were not shown.

Filtering Approaches for Every Single Field:

Although in some fields, any ASCII character can be taken as inputs, using < or > can cause false results. Please do not use them in your filtering inputs for the criterion fields.

All the text searches are case-insensitive. That means, if the input is in for example, all these texts will be matched with the input: In, in, iN, IN.

Below, the word contained is used a lot. This word means that, if the input is a substring of the searched value for the looked person, the input is contained.
e.g. if the input is ale for the name, all the persons will be chosen, who have at least one of the uppercase and lowercase combination of the input ale in their names as a substring.
e.g. if the input is ale, the person with the name Alex, aLex, ALEX, alexandra etc. will be matched.

NAME: It can take any English alphabet character and also space character. It checks if the entered criteria is contained in the names of the persons in the list.
PHONE: It can take any positive number, controls if the entered criteria is contained in the phones of the persons in the list.
EMAIL and ADDRESS: It can take any number of ASCII characters more than 0. Controls if the entered criteria is contained in the emails/addresses of the persons in the list.
GPA: It takes a positive integer or float value between 0 and 4. Shows the persons with higher or equal GPA values from the given criteria.
EDUCATION: It can take any English alphabet character and also space character. It checks if the entered criteria is contained in the school/education of the persons in the list.
SKILLS and POSITIONS:
- It can take any number of ASCII characters more than 0 (except "," in the skill/position itself).
- Multiple skills/positions can be entered with using one PREFIX and one REVERSE PREFIX as long as the skills/positions are separated with ",".
- Controls, if the given skills/positions are contained in the actual skills/positions of the persons in the list.
ENDORSEMENT-COUNT: It takes a positive integer. If the given number as an input is less than or equal to the number of endorsements (it is just the process, where a person recommended by someone) the person has, then this person is shown.
DEGREE-LEVEL:
- The input for this field can take an integer between 0 and 4 (they are included) or a text, which can be either highschool or associates or bachelors or masters or phd.
- Order of integers are matched with the order of texts given. In other words, input 0 also means highschool, 1 means associates, 2 means bachelors etc.
- In this filtering field, it is controlled that if the entered degree level is a lower or an equal level than the one for the searched person, the person will be shown in the list.

3.3.1. Current Implementation of Filter Command

Implementation Details:

Class Diagram of the Filtering Command:

Sequence Diagram of the Filtering Command:

Filtering is parsed in FilterCommandParser class, directed in FilterCommand class for further processing and actual filtering process took place in AddressBook class.
Working Principle of FilterCommandParser Class
1. The input is trimmed (spaces at the beginning and at the end are cleaned), cleared from multiple spaces and turned into lowercase form.
2. By checking the first number of characters of the input, the type of the process is determined (and, or, clear or reverse) and stored in an integer value. If the input has none of them, an invalid input message is shown.
3. Since there are 10 different fields that can be filtered, a String array with size 10, called criterion, is created and the values are set to " " in initialization.
4. If the type is clear or reverse, a new FilterCommand object is called with passing the criterion array and the process-type-holding-integer for that method. If it is not, followings take place.
5. The prefixes are searched. For each of the fields, these controls are made:
  - Checked if the PREFIX exists in the input for the searched field.
  - If it is, then REVERSE PREFIX for that field is also searched and if that is also found, it is checked that if the PREFIX is placed before REVERSE PREFIX.
  - If it is not, or if the search cannot reach to this step, then an invalid input message is shown.
  - If the steps are passed successfully, the element in the criterion array for this field will be changed to the value "available"
    e.g. if the input is filter or phone<57>phone, then the PREFIX and REVERSE PREFIX locations are correct, the 21st index (related index for the phone in the array) of the criterion will be set to "available".
  - Since the parser looks for the first occurrence of PREFIX and REVERSE PREFIX, if there are multiple filtering parts for the searched criteria, then the first one will be taken.
6. For the available fields (the ones with the regarding criterion indexes are set to "available"), an input check is made for the the text between the PREFIX and REVERSE PREFIX. For the non-available filtering conditions, the value in criterion for the related field is set to null.
7. If the parameters does not pass the input check, an error is thrown, which says the input is in invalid form. If they passes the input check, then the index for the regarding field in criterion array is set to the text value between the PREFIX and REVERSE PREFIX.
  e.g. the 1st index of criterion is set to 57 regarding to the example above.
8. FilterCommand function is called. In the parameters criterion and process-type-holding-integer passed to the object constructor.
Working Principle of FilterCommand Class
1. For each 10 fields of the filter command criterion, a string parameter is constructed and the values are set regarding the values in criterion array. If no value for that field is present, the parameter in the FilterCommand class is set to null.
2. Since SKILLS and POSITIONS fields can contain more than one criterion inside (all the criterion are separated with ", " for these), the string values in criterion array regarding to those fields are split through "," usage and the data for these are stored in String[] parameters created in FilterCommand class, instead of String parameters.
3. Also the type of the process (and, or, clear or reverse) is stored in a parameter in FilterCommand, too.
4. According to the process type, one of the methods filterAnd(), filterOr(), clearFilter() or reverseFilter() is called through Model interface and these methods in Model also called the one of these methods in AddressBook class with the same name.
5. For filterAnd() and filterOr() methods, the values for every single field are passed through the method call.
Working Principle of AddressBook Class for Filtering Purposes
- In the AddressBook class, a new UniquePersonsList parameter called allPersonsStorage is added.
- When the filtering method is used, the persons parameter in the class is updated according to the filtering criterion (the persons that are not matching the conditions are removed). However, in order not to lose data, the new added allPersonsStorage parameter is not being changed with the filtering processes. It still continues to store every single person in the application storage.
- When clearFilter() method is called, if there is a filtering available, every single person who is not in persons parameter but in allPersonsStorage are added to the persons storage. So basically, it is right to say that persons parameter only holds the persons we expect to see in the GUI.
- When reverseFilter() method is called, if there is a filtering available, every single person who is in persons parameter is replaced with the persons who were not stored in this parameter before.
- When filterOr() method is called, every single person in persons parameter is traversed and the ones that do not contain none of the criterion set through input are removed from persons.
- When filterAnd() method is called, every single person in persons parameter is traversed and the ones that do not contain even one of the criterion set through input are removed from persons.
- The information if there is a filtering available in the application, is also stored in a boolean parameter in AddressBook and set true with filterAnd() and filterOr() methods, set false with the initial launch of the application, clearFilter() call and Add Command call (because it increases the size of the data and it is not know that if the newly added person fits the filtering criterion or not).
- Filter-keeping-parameter is important, because with undo and redo commands, it is important to maintain the filtering state in order not to lose any data and in order to use clearFilter() method.

3.3.2. Alternative Approaches

In this title, both Command implementation and Parser implementation will be discussed in 2 parts:

Command Implementation

Instead of adding another parameter in AddressBook class called allPersonsStorage, another approach would be letting persons parameter to hold all the unfiltered information and updating filteredPersons parameter in the ModelManager class. filteredPersons is a list of persons that is defined in ModelManager. It is especially used in FindCommand, that applies a basic filter to the list of persons in the application with only one criteria NAME. However, filteredPersons is implemented with Predicate approach.

Pros of this approach:
- Does not need any additional permanent parameter to be created in AddressBook class.
- Decreases the number of changes made in each list changing method of the AddressBook class. Because, if any additional parameter is added to AddressBook class, all the functions have to be changed considering the new parameter.
Cons of this approach:
- It is hard and time consuming to implement this approach because Predicates are used. In AddressBook class itself, we can directly reach to the persons and their all fields easily. But with Predicate approach, it requires additional data to be built (Predicates may need to be created before adding new persons to the parameter). Moreover, we do not have much knowledge about Predicate usage and because of these reasons, our job may take more time to finish.

Parser Implementation

Instead of putting the criterion contents between both PREFIXES and REVERSE PREFIXES, we could only add the content after PREFIX (without any REVERSE PREFIX usage) like the addition process .

Pros of this approach:
- User would need to write less number of characters
Cons of this approach:
- Using also reverse prefix makes the job much easier, because it simply marks also the end of the content.
- In currently implemented version, no order of the criterion is necessary. So, first phone number and then name etc. can be added for filtering condition. However in the alternative approach, implementing the input taking with no order is harder and time consuming.

3.3.3. Testing of Filter Command Design

The testing methods for filtering is written for 3 different parts:

FilterCommandParserTests

This test class is prepared for unit testing of FilterCommandParser cass. With the tests:
- The validity of inputs with single and multiple field are present are checked.
- The given order of inputs are checked in case of any possibility for an error.
- Empty command or filter command without any type specification are checked.
- The exceptions thrown are controlled, when the criterion are empty.
- For number type of criterion, the negative and positive out of bound values, entering string values and entering valid values are checked.
- For String type of criterion, the type of characters allowed are checked.

FilterCommandTests

This test class is prepared for unit testing of Filtering Command. With these tests Filtering process are checked:
- when a single or multiple criterion are given,
- when filtering occurs multiple times,
- when type is clear or reverse and there are no/one/multiple filters are applied before.

FilterCommandIntegrationTests

This test class contains integration tests and investigates the interaction of FilterCommand with: UndoCommand, RedoCommand, AddCommand, DeleteCommand,SortCommand, FindCommand, SelectCommand, and cases, when all of them are together.
Each test case at least contains filtering with or - success or and - success, clear - success and clear - failure, reverse - success and reverse - failure.
Also for every interacting command, failure and success cases are both investigated.

3.4. Sort Commands

3.4.1. Current Implementation Summary

There are currently eleven main sorting methods present: name, surname, gpa, education, degree, skills, positions, endorsements, skill number, position number, endorsement number. There is also a complimentary reverse sort method for each main sorting method.

name is called by the user through the following cli input: sort name.
It takes the current list displayed in the left hand GUI panel and sorts them by name alphabetically. The name sort begins with the first name and then proceeds to last name.
surname is called by the user through the following cli input: sort surname.
It takes the current list displayed in the left hand GUI panel and sorts them by surname alphabetically.
gpa is called by the user through the following cli input: sort gpa.
It takes the current list displayed in the left hand GUI panel and sorts them by gpa in decreasing numeric order.
education is called by the user through the following cli input: sort education.
It takes the current list displayed in the left hand GUI panel and sorts them by education alphabetically.
degree is called by the user through the following cli input: sort degree.
It takes the current list displayed in the left hand GUI panel and sorts them by degree starting with PhD and then proceeding to Masters, Bachelors, Associates and High School in this order.
skills is called by the user through the following cli input: sort skills.
It takes the current list displayed in the left hand GUI panel and first orders the skill tags for each person alphabetically. The method then proceeds to sort all persons based on their skill tags, in alphabetical order.
positions is called by the user through the following cli input: sort positions.
It takes the current list displayed in the left hand GUI panel and first orders the position tags for each person alphabetically. The method then proceeds to sort all persons based on their position tags, in alphabetical order.
endorsements is called by the user through the following cli input: sort endorsements.
It takes the current list displayed in the left hand GUI panel and first orders the endorsements for each person alphabetically. The method then proceeds to sort all persons based on their endorsements, in alphabetical order.
skill number is called by the user through the following cli input: sort skill number.
It takes the current list displayed in the left hand GUI panel and orders the persons based on their number of skills in descending order.
position number is called by the user through the following cli input: sort position number.
It takes the current list displayed in the left hand GUI panel and orders the persons based on their number of positions in descending order.
endorsement number is called by the user through the following cli input: sort endorsement number.
It takes the current list displayed in the left hand GUI panel and orders the persons based on their number of endorsements in descending order.
reverse can be applied before the sort keyword (e.g. name) through the following cli input: sort reverse name

(the current list means that if filter is on, only those filtered persons shall be sorted and the filter shall remain on)

Intelligent Sorting:

For a recruiting company with a large number of contacts it is highly likely that certain fields shall be repeated (for example two different persons can both have Bachelors degrees). To aid the user, intelligent sorting has been implemented. It sorts persons that match in the field that the initial sort is looking at and then performs a secondary sort using a method related to the initial sort. The sequences of these are shown below.

Table 1. Flow pattern for the sorting methods
Initial Sort Method	Subsequent Sort Method (for persons with same value after first sort method)	Secondary Subsequent Sort Method (for persons with same value after first and subsequent sort method)
Name	-	-
Surname	Name	-
Skills, Positions, Endorsements	Name	-
Skills, Positions, Endorsements Number	Skills, Positions, Endorsements respectively	Name
Gpa	Name	-
Degree	GPA	Name
Education	GPA	Name

3.4.2. Current Implementation Description.

The sort command works in a similar fashion to the commands already in place. Below is a sequence diagram for a general sort method. The SortCommandParser implements the already created Parser interface. It is used to take the CLI user input and make a new SortCommand object only if a valid Sort Word has been passed into the CLI.

The SortCommand is an extension of the abstract command class. This means history, command results and addressbook committing follow the same format as the commands in place. This allows it’s compatibility with those commands already present. It takes the list of persons in the addressbook. It ensures that if a filter is present, only these filtered persons are sorted, but the complete persons list is left unaffected. This presents accidental deletion of contact information. The SortCommand class proceeds to take the input, initially from the CLI, and uses processSortMethod to call the necessary sorting method. The sorting method classes all implement the SortMethod interface which executes the necessary sort on the list and has a getList() method.

Once a correctly ordered list of persons has been retrieved by the SortCommand class, it checks for the reverse keyword and makes the necessary adaption. All the persons are then deleted from this model. Due to the severity of this command, additional care has been taken to ensure it can only be processed providing there is a list of persons (of the same length) present to replace it. It then adds the persons back into the addressbook in the correct order, taking note of the filter to ensure compatibility.

Sequence Diagram for a general sort method.

Also of note are the methods used in the sorts themselves. Below is shown the sequence diagram for a surname sorting method as an example. The sort methods begin by retrieving the field of interest to the particular sorting method. The aim is to create a Comparator<Person> which can subsequently be easily sorted either numerically or alphabetically. To retrieve the field of interest, the Person class is used. For those fields not suited to numerical or alphabetical sorting, associated values can be generated. For example in the degree field, values are given to the different levels which can then be sorted. These methods should be stored in PersonUtil to keep the frequently used Person class as clear and relevant as possible.

For the skills, positions and endorsements sorting methods, it is required for the person’s individual tags to be sorted first. This uses a sorting method on each person and the creation of new person with correctly ordered skill/position/endorsement tags. Once a comparator has been created, the SortUtil class can be used to perform the actual sorting. This makes use of Java’s stream.Collectors method.

For intelligent sorting the SortListWithDuplicates class is used. It divides the list of persons from the initial sort into smaller lists (dupPersonList) of those returning the same comparator value. These are then individually sorted by the subsequent sorting method. By utilising similar methods for each sort method, this makes the subsequent calling of further sort methods quick and easy. It is worth noting that a subsequent sorting method shall then perform a further sort if its comparator returns a duplicate value within the duplicate list. This process is terminated by the sort name method since the addressbook does not allow people to be added with the same name.

3.4.3. Implementation Rational

Sequence Diagram for the surname sort.

Despite the risk of slightly increasing the coupling, the aim was to use methods already written and rely on good cohesion. For example, once a sort command has correctly written the correctly ordered persons to a List<Person>, rather than duplicating large amounts of code by modifying the already listed persons in the GUI, it shall simply remove the persons in that addressbook version and then immediately re-add them in the correct order.

It is of note that the temporary deletion of persons from the addressbook should be foolproof and there should be no way that the sort command ever permanently deletes the addressbook. Furthermore, ensuring the command works with the already implemented undo/redo command should ensure the user still has full control over all the persons in the contact book.

The future of this product demands the dynamic addition of contact fields as they become important. These fields should then be able to be sorted. Consequently it is paramount that the addition of a further sort command is easy. This is achieved through the SortMethod interface and provision of very adaptable sorting method techniques that can be later used. The steps taken to add a new sort command are provided below.

3.4.4. Approaches Considered

When writing sort commands, there were two approaches considered: modify the indices of all persons and then refresh the left-hand GUI panel with this new list; or temporarily delete the list of persons and then add a new list of correctly ordered persons.

Elements of lists in Java are ordered by when they were added. Sorting is possible using Collections, however this requires them to be strings. Since the Recruit Me application contains lists of various object types, typically Person, there is no immediate compatibility with Collections. Furthermore it was suspected that to simply modify the indices of persons, a lot of duplicate code would be need to be written since this aspect of addressbook-level4 was not easily modifiable. Because of this the second method was opted for.

It was also decided to make this command as similar as possible in style to those already present. This meant that it was almost immediately compatible with the other commands. This way it could also make use of various methods already in place.

3.4.5. Adding a New Sort Command

To add a new sort command, the following classes should be altered accordingly:

cliSyntax - add the necessary new SortWord (and the reverse option), this should match the desired CLI user input
SortCommandParser - add the new SortWords as an accepted input
Sort[NewMethod] - a new class that implements the SortMethod interface, that will execute a sort on the list of Persons, according to the new method, and a getList() method for returning this correctly ordered list. Here a subsequent ordering method can be specified for intelligent sorting
Person - it is often useful to have a Person’s field as a string or numerical value in order to create a comparator. Consequently a method should be provided here for returning the Person’s new field as a string or number.
SortCommand - create the link between the new SortWord and the new Sort[NewMethod] class
SortUtil - a place for lower-level processes required by the new sort method and called from Sort[NewMethod]

When choosing the subsequent sort for intelligent sorting, a loop must not be created. For example matching gpa’s can’t use education as a subsequent sorting method if education is already using gpa. This is because if a person has both the same gpa and education, they can’t be sorted.

The developer should also add the necessary testing methods in SortCommandTest and SortCommandIntegrationTest

3.5. Endorse Command

3.5.1. Overview

A command for the use of company employees that want to assist in the hiring process and find the candidates that will work best in their teams.
The endorse command allows employees to select candidates by their index and create an endorsement tag to help candidates stand out in the recruiting platform.
There is a complementary 'clear' function for removing endorsement tags if an employee wants to rescind his recommendation.

3.5.2. Current Implementation

Endorsing mechanism is facilitated by AddressBook. Like other commands, the Logic Manager parses the user input and recognizes the 'endorse' keyword as the user calling the endorse command and sending the arguments to the EndorseCommandParser. The parser then interprets the specified index as an Index object and identifies the candidate to endorse. A new tag of type 'endorse' is created and added to the set of tags associated with the specific Person object. The tag is shaded teal to represent an endorsement and a "e:" prefix is added to the tag name in order to save the color correctly as a JsonAdaptedTag (as described in Section 3.2: Colored Tags).

Clearing Endorsements

Endorsing can be reversed through the 'clear' keyword. When an employee has previously endorsed a candidate and then wants to remove that endorsement, he or she can include 'clear' in their endorse command input before the index is specified. The EndorseCommandParser recognizes the clear command and specifies that this is a clearing process in the instantiation of a new EndorseCommand object. To specify a normal endorse command, the EndorseCommand object is passed a process code of 0 in the constructor and a process code of 1 to show that a clearing command has been called. The object recognizes the passing of a clearing process and removes the tag of the specified employee in the Person class.

Incorporation With Other Commands

Add and Edit Commands

The add command does not have prefixes for creating endorsement tags so that candidates cannot add any company endorsements when they add themselves to the platform or when they edit their profile.

Because endorsements are only created and removed by employees, they are saved as part of the candidate profile and cannot be changed by a candidate editing their skills and position tags. If a candidate adds or removes tags from their profile, any employee endorsements that they have received will be maintained.

Filter and Sort Commands

In order for the command to be functional in a filtered or sorted view, the candidate is found in the model through the filtered persons list. When a user filters by specified parameters and/or sorts the results by a profile characteristic, using the endorse command on the new indexed results will still result in a successful endorsement of the correct candidate.

3.5.3. Endorse Command Tests

Tests the implementation of the endorse command and the endorse clear command. Checks that the endorse command correctly creates an endorsement tag and endorses the correct indexed person. Also checks that the endorse clear command removes an endorsement tag from the correct indexed person. The following use cases are tested:

Endorses the correct index and correct person at the specified index
Clears endorsement of correct person at the correct index
Accepts a valid employee name
Accepts a valid integer as the index
Cannot endorse a candidate more than once
Cannot clear an endorsement that has never been made

3.5.4. Alternate Implementation

Coming in v2.0

Separating exclusive features for different users so that only candidates can change their skills and only employees can endorse candidates. We will differentiate the experiences that the distinct users (candidates, recruiters, and employees) can have with the platform and make a more individual view for each person. Distinguishing which user is using the system will allow us to prevent some users from using functions that are only meant for others, such as candidates using the endorse function or employees editing a candidate profile.

3.6. [Proposed] Data Encryption

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

3.7. Logging

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

The logging level can be controlled using the logLevel setting in the configuration file (See Section 3.8, “Configuration”)
The Logger for a class can be obtained using LogsCenter.getLogger(Class) which will log messages according to the specified logging level
Currently log messages are output through: Console and to a .log file.

Logging Levels

SEVERE : Critical problem detected which may possibly cause the termination of the application
WARNING : Can continue, but with caution
INFO : Information showing the noteworthy actions by the App
FINE : Details that is not usually noteworthy but may be useful in debugging e.g. print the actual list instead of just its size

3.8. Configuration

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

[[Implementation-Sort Commands]] === Sort Commands

Elements of lists in Java are ordered by when they were added. Sorting is possible using Collections, however this requires them to be strings. Since the Recruit Me application contains lists of various types, typically Person, there is no immediate compatibility with Collections. Furthermore it was suspected that to simply modify the indices of persons, a lot of duplicate code would be need to be written since this aspect of addressbooklevel4 was not easily modifiable. Because of this the second method was opted for.

Despite the risk of slightly increasing the coupling, the aim was to use methods already written and rely on good cohesion. For example, once a sort command has correctly written the correctly ordered persons to a List<Person>, rather than duplicating large amounts of code by modifying the already listed persons, it shall use the already written delete person and add person commands.

It is of note that the temporary deletion of persons from the addressbook should be foolproof and there should be no way that the sort command ever permenantly deltes the addressbook. Furthermore, ensuring the command works with the already implemented undo/redo command should ensure the user still has full control over all the persons in the contact book.

To add a new sort command, the following should be taken into account… (INSERT CLASS DIAGRAM)

Two sorting methods are currently present: alphabetical and skills…

=== Education and GPA

New parameters for perspective employees to add to their information. Employers are able to look at this information to determine if the person is suitable for the position at the company. Education and GPA can be use to filer or sort the perspective employees.

Education

New parameter to specify the level of schooling achieved by the perspective employee.

GPA

New parameter for the grade point average achieved by the perspective employee.

NOT COMPLETE.

== 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.

=== 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.

=== Publishing Documentation

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

=== Converting Documentation to PDF format

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

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

Follow the instructions in UsingGradle.adoc to convert the AsciiDoc files in the docs/ directory to HTML format.
Go to your generated HTML files in the build/docs folder, right click on them and select Open with → Google Chrome.
Within Chrome, click on the Print option in Chrome’s menu.
Set the destination to Save as PDF, then click Save to save a copy of the file in PDF format. For best results, use the settings indicated in the screenshot below.

Figure 9. Saving documentation as PDF files in Chrome

=== Site-wide Documentation Settings

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

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

Table 2. List of site-wide attributes
Attribute name	Description	Default value
`site-name`	The name of the website. If set, the name will be displayed near the top of the page.	not set
`site-githuburl`	URL to the site’s repository on GitHub. Setting this will add a "View on GitHub" link in the navigation bar.	not set
`site-seedu`	Define this attribute if the project is an official SE-EDU project. This will render the SE-EDU navigation bar at the top of the page, and add some SE-EDU-specific navigation items.	not set

=== Per-file Documentation Settings

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

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

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

Table 3. List of per-file attributes, excluding Asciidoctor’s built-in attributes
Attribute name	Description	Default value
`site-section`	Site section that the document belongs to. This will cause the associated item in the navigation bar to be highlighted. One of: `UserGuide`, `DeveloperGuide`, `LearningOutcomes`, `AboutUs`, `ContactUs` Official SE-EDU projects only	not set
`no-site-header`	Set this attribute to remove the site navigation bar.	not set

=== Site Template

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

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

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

== Testing

=== 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)

=== Types of tests

We have two types of tests:

GUI Tests - These are tests involving the GUI. They include,
1. System Tests that test the entire App by simulating user actions on the GUI. These are in the systemtests package.
2. Unit tests that test the individual components. These are in seedu.address.ui package.
Non-GUI Tests - These are tests not involving the GUI. They include,
1. Unit tests targeting the lowest level methods/classes.
  e.g. seedu.address.commons.StringUtilTest
2. Integration tests that are checking the integration of multiple code units (those code units are assumed to be working).
  e.g. seedu.address.storage.StorageManagerTest
3. Hybrids of unit and integration tests. These test are checking multiple code units as well as how the are connected together.
  e.g. seedu.address.logic.LogicManagerTest

=== Troubleshooting Testing Problem: HelpWindowTest fails with a NullPointerException.

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

== Dev Ops

=== Build Automation

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

=== Continuous Integration

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

=== Coverage Reporting

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

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

=== 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.

=== Managing Dependencies

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

Include those libraries in the repo (this bloats the repo size)
Require developers to download those libraries manually (this creates extra work for developers)

== 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 [GetStartedProgramming-EachComponent].
Next, add a feature that touches multiple components to learn how to implement an end-to-end feature across all components. [GetStartedProgramming-RemarkCommand] explains how to go about adding such a feature.

=== Improving each component

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

`Logic` component

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

Do take a look at Section 2.3, “Logic component” before attempting to modify the Logic component.

Add a shorthand equivalent alias for each of the individual commands. For example, besides typing clear, the user can also type c to remove all persons in the list.
- Hints
  
  Just like we store each individual command word constant COMMAND_WORD inside *Command.java (e.g. FindCommand#COMMAND_WORD, DeleteCommand#COMMAND_WORD), you need a new constant for aliases as well (e.g. FindCommand#COMMAND_ALIAS).
  
  AddressBookParser is responsible for analyzing command words.
- Solution
  
  Modify the switch statement in AddressBookParser#parseCommand(String) such that both the proper command word and alias can be used to execute the same intended command.
  
  Add new tests for each of the aliases that you have added.
  
  Update the user guide to document the new aliases.
  
  See this PR for the full solution.

`Model` component

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

Do take a look at Section 2.4, “Model component” before attempting to modify the Model component.

Add a removeTag(Tag) method. The specified tag will be removed from everyone in the address book.
- Hints
  
  The Model and the AddressBook API need to be updated.
  
  Think about how you can use SLAP to design the method. Where should we place the main logic of deleting tags?
  
  Find out which of the existing API methods in AddressBook and Person classes can be used to implement the tag removal logic. AddressBook allows you to update a person, and Person allows you to update the tags.
- Solution
  
  Implement a removeTag(Tag) method in AddressBook. Loop through each person, and remove the tag from each person.
  
  Add a new API method deleteTag(Tag) in ModelManager. Your ModelManager should call AddressBook#removeTag(Tag).
  
  Add new tests for each of the new public methods that you have added.
  
  See this PR for the full solution.

`Ui` component

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

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

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

Before

After
- Hints
  
  The tag labels are created inside the PersonCard constructor (new Label(tag.tagName)). JavaFX’s Label class allows you to modify the style of each Label, such as changing its color.
  
  Use the .css attribute -fx-background-color to add a color.
  
  You may wish to modify DarkTheme.css to include some pre-defined colors using css, especially if you have experience with web-based css.
- Solution
  
  You can modify the existing test methods for PersonCard 's to include testing the tag’s color as well.
  
  See this PR for the full solution.
  
  The PR uses the hash code of the tag names to generate a color. This is deliberately designed to ensure consistent colors each time the application runs. You may wish to expand on this design to include additional features, such as allowing users to set their own tag colors, and directly saving the colors to storage, so that tags retain their colors even if the hash code algorithm changes.
Modify NewResultAvailableEvent such that ResultDisplay can show a different style on error (currently it shows the same regardless of errors).

Before

After
- Hints
  
  NewResultAvailableEvent is raised by CommandBox which also knows whether the result is a success or failure, and is caught by ResultDisplay which is where we want to change the style to.
  
  Refer to CommandBox for an example on how to display an error.
- Solution
  
  Modify NewResultAvailableEvent 's constructor so that users of the event can indicate whether an error has occurred.
  
  Modify ResultDisplay#handleNewResultAvailableEvent(NewResultAvailableEvent) to react to this event appropriately.
  
  You can write two different kinds of tests to ensure that the functionality works:
  
  The unit tests for ResultDisplay can be modified to include verification of the color.
  
  The system tests AddressBookSystemTest#assertCommandBoxShowsDefaultStyle() and AddressBookSystemTest#assertCommandBoxShowsErrorStyle() to include verification for ResultDisplay as well.
  
  See this PR for the full solution.
  
  Do read the commits one at a time if you feel overwhelmed.
Modify the StatusBarFooter to show the total number of people in the address book.

Before

After
- Hints
  
  StatusBarFooter.fxml will need a new StatusBar. Be sure to set the GridPane.columnIndex properly for each StatusBar to avoid misalignment!
  
  StatusBarFooter needs to initialize the status bar on application start, and to update it accordingly whenever the address book is updated.
- Solution
  
  Modify the constructor of StatusBarFooter to take in the number of persons when the application just started.
  
  Use StatusBarFooter#handleAddressBookChangedEvent(AddressBookChangedEvent) to update the number of persons whenever there are new changes to the addressbook.
  
  For tests, modify StatusBarFooterHandle by adding a state-saving functionality for the total number of people status, just like what we did for save location and sync status.
  
  For system tests, modify AddressBookSystemTest to also verify the new total number of persons status bar.
  
  See this PR for the full solution.

`Storage` component

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

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

Add a new method backupAddressBook(ReadOnlyAddressBook), so that the address book can be saved in a fixed temporary location.
- Hint
  
  Add the API method in AddressBookStorage interface.
  
  Implement the logic in StorageManager and JsonAddressBookStorage class.
- Solution
  
  See this PR for the full solution.

=== Creating a new command: remark

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

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

==== 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.

==== Step-by-step Instructions

===== [Step 1] Logic: Teach the app to accept 'remark' which does nothing Let’s start by teaching the application how to parse a remark command. We will add the logic of remark later.

Main:

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

Tests:

Add RemarkCommandTest that tests that execute() throws an Exception.
Add new test method to AddressBookParserTest, which tests that typing "remark" returns an instance of RemarkCommand.

===== [Step 2] Logic: Teach the app to accept 'remark' arguments Let’s teach the application to parse arguments that our remark command will accept. E.g. 1 r/Likes to drink coffee.

Main:

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

Tests:

Modify RemarkCommandTest to test the RemarkCommand#equals() method.
Add RemarkCommandParserTest that tests different boundary values for RemarkCommandParser.
Modify AddressBookParserTest to test that the correct command is generated according to the user input.

===== [Step 3] Ui: Add a placeholder for remark in PersonCard Let’s add a placeholder on all our PersonCard s to display a remark for each person later.

Main:

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

Tests:

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

===== [Step 4] Model: Add Remark class We have to properly encapsulate the remark in our Person class. Instead of just using a String, let’s follow the conventional class structure that the codebase already uses by adding a Remark class.

Main:

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

Tests:

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

===== [Step 5] Model: Modify Person to support a Remark field Now we have the Remark class, we need to actually use it inside Person.

Main:

Add getRemark() in Person.
You may assume that the user will not be able to use the add and edit commands to modify the remarks field (i.e. the person will be created without a remark).
Modify SampleDataUtil to add remarks for the sample data (delete your data/addressbook.json so that the application will load the sample data when you launch it.)

===== [Step 6] Storage: Add Remark field to JsonAdaptedPerson class We now have Remark s for Person s, but they will be gone when we exit the application. Let’s modify JsonAdaptedPerson to include a Remark field so that it will be saved.

Main:

Add a new JSON field for Remark.

Tests:

Fix invalidAndValidPersonAddressBook.json, typicalPersonsAddressBook.json, validAddressBook.json etc., such that the JSON tests will not fail due to a missing remark field.

===== [Step 6b] Test: Add withRemark() for PersonBuilder Since Person can now have a Remark, we should add a helper method to PersonBuilder, so that users are able to create remarks when building a Person.

Tests:

Add a new method withRemark() for PersonBuilder. This method will create a new Remark for the person that it is currently building.
Try and use the method on any sample Person in TypicalPersons.

===== [Step 7] Ui: Connect Remark field to PersonCard Our remark label in PersonCard is still a placeholder. Let’s bring it to life by binding it with the actual remark field.

Main:

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

Tests:

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

===== [Step 8] Logic: Implement RemarkCommand#execute() logic We now have everything set up… but we still can’t modify the remarks. Let’s finish it up by adding in actual logic for our remark command.

Main:

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

Tests:

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

==== Full Solution

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

== Product Scope - Target user profile

General Needs:

has a need to manage a significant number of contacts
prefer desktop apps over other types
can type fast
prefers typing over mouse input
is reasonably comfortable using CLI apps

Special Needs:

this is an application for recruitment agency specifically
the commands (filtering, sorting, deleting, adding etc.) and tags (education, experience etc.) are designed for applicants

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

== 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…
`* * *`	new user	see usage instructions	refer to instructions when I forget how to use the App
`* * *`	user	add a new person
`* * *`	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
`* *`	user	hide private contact details by default	minimize chance of someone else seeing them by accident
`* *`	user with many persons in the address book	sort persons by name	locate a person easily
`* *`	user with many persons in the address book	filter persons by any of the multiple properties at the same time	see which persons are fit into the criterion
`* *`	user with many persons in the address book	use all the other operations when filtering is active	locate the searched persons more easily
`* *`	user with many persons in the address book	disable the active filtering	see all the list when the job is done
`* *`	user with many persons in the address book	undo the operation what he/she just did	prevent false updates in the address book
`* *`	user with many persons in the address book	redo the operation what he/she just did	prevent false undo operations in the address book
`* *`	user with many persons in the address book	see the education level, technical skills and experience of the persons	choose persons regarding more information given.

* * *

new user

see usage instructions

refer to instructions when I forget how to use the App

* * *

user

add a new person

* * *

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

* *

user

hide private contact details by default

minimize chance of someone else seeing them by accident

* *