☀️ WeatherApp MVC in Clprolf Framework

Everyone knows the MVC pattern.

Let’s look at a simple example:
a WeatherApp written in Java + Clprolf framework —
which behaves like a Spring MVC application,
but runs locally in Swing.

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🧠 1. The Idea Behind It

In Spring MVC, a Controller receives a request,
calls a Repository or Service,
and returns a View.

In Clprolf, we do exactly the same —
but we explicitly declare the roles of each component.

Component	Clprolf Role	Description
WeatherApp	@ClWorker	The system launcher (like Spring Boot main)
WeatherController	@ClAgent	The “brain” that coordinates the logic
WeatherRepository	@ClWorker	Technical layer fetching data
WeatherRenderer	@ClWorker	The View layer (UI and user input)

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🏗️ 2. The Complete Code

package org.clprolf.examples.design_patterns.mvc;

import org.clprolf.framework.java.Worker;

@ClWorker
public class WeatherApp {
    public static void main(String[] args) {
        WeatherController controller = new WeatherController();
    }
}

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🧩 Controller (Agent Layer)

package org.clprolf.examples.design_patterns.mvc;

import org.clprolf.framework.java.Agent;

@ClAgent
public class WeatherController {
    private WeatherRepository model;
    private WeatherRenderer view;

    public WeatherController() {
        model = new WeatherRepository();
        view = new WeatherRenderer(this);
    }

    public void giveTheWeather(String location){
        model.setLocation(location);
        model.fetchWeather();
        String forecast = model.getForecast();
        view.displayForecast(forecast);
    }
}

This class acts like a Spring @Controller:
it receives a request (giveTheWeather),
calls the repository,
and updates the view.

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🎨 View (Worker Layer)

package org.clprolf.examples.design_patterns.mvc;

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;

import org.clprolf.framework.java.Agent;
import org.clprolf.framework.java.Worker;

@ClWorker
public class WeatherRenderer {

    private JFrame frame;
    private JTextField locationField;
    private JTextArea forecastArea;
    private WeatherController expert;

    @ClAgent
    @ClFamily
    private static interface WindowObserver extends ActionListener { }

    @ClAgent
    private class WindowObserverImpl implements WindowObserver {

        @Override
        public void actionPerformed(ActionEvent e) {
            String location = getLocationInput();
            this.expert.giveTheWeather(location);
        }
    }

    public WeatherRenderer(WeatherController expert) {
        this.expert = expert;
        prepareViewObjects();
    }

    protected void prepareViewObjects() {
        frame = new JFrame("Weather Forecast");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 200);

        JPanel panel = new JPanel(new BorderLayout());
        JLabel locationLabel = new JLabel("Enter Location:");
        locationField = new JTextField(20);
        locationField.addActionListener(new WindowObserverImpl());

        forecastArea = new JTextArea(5, 30);
        forecastArea.setEditable(false);

        panel.add(locationLabel, BorderLayout.NORTH);
        panel.add(locationField, BorderLayout.CENTER);
        panel.add(new JScrollPane(forecastArea), BorderLayout.SOUTH);

        frame.getContentPane().add(panel);
        frame.setVisible(true);
    }

    public String getLocationInput() {
        return locationField.getText();
    }

    public void displayForecast(String forecast) {
        forecastArea.setText(forecast);
    }
}

Here, the view acts like a web frontend.
It observes user input (capacity-inherited ActionListener)
and sends the event to the controller agent.

You could almost replace Swing with HTML/JavaScript
and it would behave the same way!

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☁️ Repository (Technical Worker)

package org.clprolf.examples.design_patterns.mvc;

import org.clprolf.framework.java.Worker;

@ClWorker
class WeatherRepository {
    private String location;
    private String forecast;

    public void setLocation(String location) {
        this.location = location;
    }

    public void fetchWeather() {
        this.forecast = "Sunny with a chance of clouds";
    }

    public String getForecast() {
        return forecast;
    }
}

A pure worker: no intelligence, no UI — just technical work.
That’s exactly what a Repository or Service does in Spring MVC.

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🔄 3. The MVC Flow

User (View) → WeatherRenderer (worker)
             → WeatherController (agent)
             → WeatherRepository (worker)
             → back to WeatherRenderer

The same logical flow as Spring MVC —
but here, everything runs locally and instantly.

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🧠 4. Why It Matters

This example shows that Clprolf framework integrates seamlessly with existing patterns.
It doesn’t replace MVC, Spring, or OOP —
it simply clarifies and strengthens them.

In a Spring app, you’d just change the way communication happens
(HTTP + @GetMapping instead of direct calls) —
but your roles, responsibilities, and architecture remain identical.

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💬 5. Final Thoughts

Clprolf makes architecture visible.
You no longer guess what a class is supposed to be:
you declare it — explicitly.

A Controller is an Agent.
A Repository is a Worker.
A Launcher is a Worker.
A View is also a Worker — the interface between human and machine.

In short:
Clprolf doesn’t reinvent MVC — it makes it self-explanatory.

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🧡 Summary

Traditional Role	Clprolf Equivalent	Layer
Controller	@ClAgent	Logic / Domain
Repository	@ClWorker	Data / Technical
View	@ClWorker	Presentation
Launcher	@ClWorker	System entry

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