Building a Java Application: An Interactive Virtual Guide to Barcelona

Hello there, fellow Java enthusiasts! Today's project is about creating an interactive virtual guide to Barcelona; an application that provides users with information about landmarks, historical sites, local cuisine, public transportation and more in the beautiful city of Barcelona.

As with most of our projects, we're going to start by setting up the project environment. Let's create a new Java project in our favourite IDE. We'll call it "BarcelonaGuide". We'll use several libraries, most notably Google's Gson library for working with JSON, and the JavaFX library to create a user-friendly, interactive UI. We'll fetch the data about Barcelona from an API, so that the information is always up-to-date.

import com.google.gson.Gson;
import javafx.application.Application;
import javafx.scene.control.Menu;

Next comes the heart of our program, our data models. The "Landmark" class contains information about a single landmark (name, location, brief history). The "Transportation" class includes information on different modes of transportation available in various areas. Lastly, the "Cuisine" class encapsulates details about local dishes and where to find them.

public class Landmark {
    private String name;
    private String location;
    private String history;
    
    // Getters and Setters...
}

public class Transportation {
    private String type;
    private String area;
    
    // Getters and Setters...
}

public class Cuisine {
    private String dishName;
    private String restaurantName;
    
    // Getters and Setters...
}

Our application will fetch information from the API and parse it into these classes. This is where the Gson library comes into play. Gson makes it easy to parse JSON into our classes. It also provides methods to convert back into JSON, if needed.

Gson gson = new Gson();
Landmark landmark = gson.fromJson(jsonString, Landmark.class);

Having designed our backend, it's time to focus on creating a visually appealing and interactive frontend using JavaFX. It consists of different menus for landmarks, transportation, and cuisine which users can browse, search, and interact with.

Menu landmarkMenu = new Menu("Landmarks");
Menu transportationMenu = new Menu("Transportation");
Menu cuisineMenu = new Menu("Cuisine");

Under each menu, a list of items will be displayed, pulled from their corresponding classes, ensuring consistent and current data is always used.

After setting up our menus, we add a map view so that users can visualize the locations of landmarks and restaurants. We'll use JavaFX's WebView for this, displaying a Google Maps webpage focused on Barcelona.

As with any software development project, constant testing and debugging are crucial. Along the way, ensure to test your application on various scenarios to cover as many corners as possible.

With persistence and ingenuity, you'll soon have your Java application offering a virtual tour of Barcelona's landmarks, local cuisines and public transportation options. Enjoy developing this exciting project, and of course, happy coding!