MVC Pattern

// ─── EXAMPLE 1 ──────────────────────────────────────────────────────────────
// WHAT WE ARE IMPLEMENTING:
// A student details manager separating database tables from HTML UI widgets.
//
// WHERE THE MVC FITS IN:
// StudentModel is the Model. StudentView represents the View.
// StudentController acts as the Controller coordinating data updates and UI
// rerenders.
// ────────────────────────────────────────────────────────────────────────────
// --- Model ---
class TaskModel {
    private String title;
    private boolean completed;

    public TaskModel(String title) { this.title = title; this.completed = false; }
    public String getTitle() { return title; }
    public boolean isCompleted() { return completed; }
    public void setCompleted(boolean completed) { this.completed = completed; }
}

// --- View ---
class TaskView {
    public void displayTask(TaskModel task) {
        String status = task.isCompleted() ? "[✓]" : "[ ]";
        System.out.println(status + " " + task.getTitle());
    }

    public void showError(String message) {
        System.out.println("ERROR: " + message);
    }
}

// --- Controller ---
class TaskController {
    private final TaskModel model;
    private final TaskView view;

    public TaskController(TaskModel model, TaskView view) {
        this.model = model;
        this.view = view;
    }

    public void markComplete() {
        model.setCompleted(true);
        view.displayTask(model);
    }

    public void render() {
        view.displayTask(model);
    }
}

public class Main {
    public static void main(String[] args) {
        TaskModel model = new TaskModel("Buy groceries");
        TaskView view = new TaskView();
        TaskController controller = new TaskController(model, view);

        controller.render();
        controller.markComplete();
    }
}