Prototype Design Pattern

Overview

The Prototype Design Pattern is used to create duplicate objects while ensuring performance. It allows for cloning objects, which is particularly useful when object creation is expensive or complex.

Key Characteristics

• Enables cloning of objects without relying on their concrete classes.
• Reduces the cost of creating objects by reusing existing ones.
• Provides a way to create object copies with minimal overhead.

Implementation

The following is an example of a Prototype implementation in Java:

interface Prototype {
    Prototype clone();
}

class ConcretePrototype implements Prototype {
    private String data;

    public ConcretePrototype(String data) {
        this.data = data;
    }

    public String getData() {
        return data;
    }

    @Override
    public Prototype clone() {
        return new ConcretePrototype(this.data);
    }

    @Override
    public String toString() {
        return "ConcretePrototype{data='" + data + "'}";
    }
}

public class PrototypeDemo {
    public static void main(String[] args) {
        ConcretePrototype prototype = new ConcretePrototype("Initial Data");
        ConcretePrototype clonedPrototype = (ConcretePrototype) prototype.clone();

        System.out.println(prototype);
        System.out.println(clonedPrototype);
    }
}
    

When to Use

• When object creation is costly in terms of time or resources.
• When you need to create multiple objects that are similar but not exact copies.

Advantages

• Reduces the cost of creating objects by reusing existing ones.
• Decouples object creation from their specific classes.

Disadvantages

• Cloning complex objects with nested structures can be challenging.
• Requires all objects to implement a clone method.

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