Implement the push(), pop(), and peek() methods for efficient execution using an ArrayListbacking store. Since you can use the ArrayList to do much of the work, you must also write a class of JUnit test methods provide 100% coverage of your methods.

import java.util.ArrayList; import java.util.EmptyStackException;

/** * Class which wraps Java's built-in {@link ArrayList} implementation so that it adds & removes elements from the end of * the List to improve efficiency AND uses the traditional method names. * * @param Type of data stored within this Stack. */ public class ProperStack { /** * The actual Stack in which all the elements will be stored. This is protected (and not private) so that students can * use this field in the test cases they create.. */ protected ArrayList store;

/** Create a new (empty) instance of this class. */ public ProperStack() { store = new ArrayList<>(); }

/** * Adds an item to the end of the stack. Traditionally, this is the only method available to add data to a Stack. * * @param item Element to be added to the end of the stack. * @return Element added to the Stack (e.g., {@code item}). */ public E push(E item) {

}

/** * Removes and returns the element at the top of this Stack. Traditionally, this is the only method available to * remove data from the Stack. * * @return Element that was removed from the top of the Stack. * @throws EmptyStackException Thrown when the Stack does not have any elements to remove. */ public E pop() {

}

/** * Like {@link #pop()}, this returns the element at the top of the Stack, but unlike {@link #pop} this method DOES NOT * remove the element. * * @return Element that is at the top of the Stack. */ public E peek() {

} }