Can you explain what is meant by creating a full copy of an object in programming?

Creating a deep copy of an object means creating a new object that is an exact copy of the original, including all nested objects and data structures. Unlike shallow copying, which only copies references to nested objects, deep copying creates new instances of all nested objects.

This is important when you want to avoid unwanted changes to the original object when modifying the copy, especially if the object contains mutable fields or collections.

Example of deep copying in Java:

class Person implements Cloneable {
    String name;
    Address address; // Address is a separate class

    @Override
    protected Object clone() throws CloneNotSupportedException {
        Person cloned = (Person) super.clone();
        cloned.address = (Address) address.clone(); // deep copy of nested object
        return cloned;
    }
}

Here, the clone method creates a new Person object and a new Address object so that changes in the copy do not affect the original.