Internet Package Registration (JavaFX)

A JavaFX desktop app for registering internet service contracts: a form with validation on top, a table of all contracts below. Built with FXML, JavaFX properties and a custom CSS dark theme, split into models and controllers (MVC).

Features

• Register a contract: person (first name, last name, email, gender), address, speed, bandwidth, duration
• Validation of the person and the package, with error dialogs listing every problem
• TableView with 8 columns, bound to an ObservableList; add and delete update it automatically
• Delete the selected row (with a message if nothing is selected)
• Clear buttons for the person part and the package part of the form
• Custom dark theme (CSS), icon buttons and icon column headers
• Undecorated window with its own close button, draggable with the mouse
• Three sample contracts loaded at start

Package options

Parameter	Values
Speed (Mbit/s)	2, 5, 10, 20, 50, 100
Bandwidth (GB)	1, 5, 10, 100, Flat
Duration	1 year, 2 years

Tech

Java 17+, JavaFX 21 (FXML, CSS), Maven. Scene layout can be opened in SceneBuilder.

Project structure

src/main/java/my/
├── Launcher.java              # entry point
├── MainApplication.java       # loads FXML + CSS, window setup, dragging
├── models/                    # Person, NetPackage + enums Gender, Speed, Bandwidth, Duration
└── controllers/               # NetPackageController, ShowAlerts
src/main/resources/my/
├── netpackage_view.fxml       # layout
├── style.css                  # theme
└── icons/                     # button and column icons

Run

Requirements: JDK 17+, Maven 3.6+.

git clone https://github.com/jlnMldnvc/<repo-name>.git
cd <repo-name>
mvn clean javafx:run

Or in IntelliJ IDEA: run my.Launcher.

How it works

Form bound to a model. The person fields are bound bidirectionally to a Person object, so clearing the model clears the form:

firstNameField.textProperty().bindBidirectional(formPerson.firstNameProperty());

Table bound to a list. Each contract is its own object with its own Person:

netPackageTableView.setItems(netPackages);          // ObservableList<NetPackage>
personFirstNameColumn.setCellValueFactory(cell ->
        cell.getValue().getPerson().firstNameProperty());

Enums with display labels. Speed, Bandwidth, Duration and Gender override toString(), so the same enum fills the ComboBox and the table cell.

Validation in the model. Person.isValid() and NetPackage.isValid() collect error messages; ShowAlerts shows them in one dialog.

Starting point and what I changed

The project started from an introductory JavaFX exercise: a single Person form with a TableView. I extended it into a different application:

Starting exercise	This project
One model (Person)	Person + NetPackage (5 properties) + 4 enums
Everything in one package, one controller	models/ and controllers/ packages, ShowAlerts helper
Gender chosen with ToggleButtons, switch on node ids	ComboBox<Gender> bound to an enum
Delete by selected index (fails with nothing selected)	Delete by selected item, with a check and message
Columns via PropertyValueFactory	Type-safe lambda cell value factories
Default look, SplitPane layout	GridPane/VBox layout, custom CSS theme, icons, draggable undecorated window
Errors stored as a list in a property	ObservableList<String> of errors inside each model, validated at person and package level

The original exercise is kept in examples/person-form/ for comparison.

Manual test checklist

• App starts, table shows 3 sample contracts
• Valid form → new row appears; empty required fields → error dialog
• Delete with a selection removes the row; without selection shows a message
• Clear Person / Clear Package reset only their own fields
• Close button exits the app

Known limitations / next steps

• Data is kept in memory only (lost when the app closes)
• Email is only checked for being non-empty
• Next: save to a file or database (SQL via JDBC / Spring Data), unit tests for validation

Credits

Icons: Google Material Symbols (Apache License 2.0).

License

MIT