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Memento

Theory

Mutations

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This task is pretty simple: you must finish the implementation of the Memento pattern. The class named Originator has only one field that contains a List of integer numbers. The class named Caretaker implements the logic of saving the state of an instance of Originator to a variable named snapshot and restore the state of the Originator instance from snapshot. The only part missing is the Memento component.

Your task is to create a class that will embody a snapshot of the state of the Originator class and implement the logic of the getMemento and setMemento methods in Originator. You may use any name for your class but do not forget to specify the proper type of the snapshot variable in Caretaker, as well as the return type of the getMemento method and the type of the parameter of the setMemento method in Originator.

Also, keep mutability in mind.

Write a program in Java 17
import java.util.*;

class Originator {
private List<Integer> numbers = new ArrayList<>();

public void addNumber(Integer number) {
numbers.add(number);
}

public List<Integer> getNumbers() {
return numbers;
}

public /* specify type */ getMemento() {

}

public void setMemento(/* specify type */ memento) {

}
}

class Caretaker {
private final Originator originator;
private /* specify type */ snapshot = null;

Caretaker(Originator originator) {
this.originator = originator;
}

public void save() {
snapshot = originator.getMemento();
}

public void restore() {
if (snapshot != null) {
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