Where and when have you used the Prototype pattern?

The Prototype pattern is used when there is a need to create many similar objects with minimal costs. For example, when working with a user interface to create identical visual elements or when generating data for tests.

A specific example: creating a series of Image objects for display in a gallery. Instead of loading and processing each image separately, a single "prototype" Image object with common properties (such as size, effects) is created, and then its instances are cloned, with only the file path changed for each.

// Prototype implementation example
public class Image implements Cloneable {
    private String filePath;
    private int width;
    private int height;

    public Image(String filePath, int width, int height) {
        this.filePath = filePath;
        this.width = width;
        this.height = height;
    }

    // Getters and setters

    @Override
    protected Object clone() throws CloneNotSupportedException {
        // Shallow copy
        return super.clone();
    }

    // Method to display the image
    public void display() {
        System.out.println("Displaying image: " + filePath + " (" + width + "x" + height + ")");
    }
}

public class ImageGallery {
    private Image prototypeImage;

    public ImageGallery(int width, int height) {
        // Create a prototype with common properties
        this.prototypeImage = new Image(null, width, height);
    }

    public Image createImage(String filePath) {
        try {
            // Clone the prototype
            Image newImage = (Image) prototypeImage.clone();
            // Set specific property
            newImage.setFilePath(filePath);
            return newImage;
        } catch (CloneNotSupportedException e) {
            e.printStackTrace();
            return null;
        }
    }

    public static void main(String[] args) {
        ImageGallery gallery = new ImageGallery(800, 600);

        // Create images based on the prototype
        Image img1 = gallery.createImage("path/to/image1.jpg");
        Image img2 = gallery.createImage("path/to/image2.png");
        Image img3 = gallery.createImage("path/to/image3.gif");

        img1.display();
        img2.display();
        img3.display();
    }
}