1. write the implementation class of this

/** * Set is an interface that describes the operations of the ADT set. A set is a * homogeneous collection of objects. It is unordered, there are no limits on * the number of items it can store, and it cannot contain duplicate items. */ public interface SetInterface {

/** * Determines the current number of entries in this set. * * @return The integer number of entries currently in this set */ public int getSize();

/** * Determines whether this set is empty. * * @return true if this set is empty; false if not */ public boolean isEmpty();

/** * Adds a new entry to this set, avoiding duplicates. * *

If newEntry is not null, this set does not contain newEntry, and this * set has available capacity (if applicable), then add modifies the set so * that it contains newEntry. All other entries remain unmodified. * Duplicates are determined using the .equals() method. * *

If newEntry is null, then add throws NullPointerException without * modifying the set. If this set already contains newEntry, then add * returns false without modifying the set. If this set has a capacity * limit, and does not have available capacity, then add throws * SetFullException without modifying the set. If this set does not have a * capacity limit (i.e., if it resizes as needed), then it will never throw * SetFullException. * * @param newEntry The object to be added as a new entry * @return true if the addition is successful; false if the item already is * in this set * @throws SetFullException If this set has a fixed capacity and does not * have the capacity to store an additional entry * @throws NullPointerException If newEntry is null */ public boolean add(E newEntry) throws SetFullException, NullPointerException;

/** * Removes a specific entry from this set, if possible. * *

If this set contains the entry, remove modifies the set so that it no * longer contains entry. All other entries remain unmodified. Identifying * this entry is accomplished using the .equals() method. The removed entry * will be returned. * *

If this set does not contain entry, remove will return null without * modifying the set. Because null cannot be added, a return value of null * will never indicate a successful removal. * *

If the specified entry is null, then remove throws * NullPointerException without modifying the set. * * @param entry The entry to be removed * @return The removed entry if removal was successful; null otherwise * @throws NullPointerException If entry is null */ public E remove(E entry) throws NullPointerException;

/** * Removes an arbitrary entry from this set, if possible. * *

If this set contains at least one entry, remove will modify the set * so that it no longer contains one of its entries. All other entries * remain unmodified. The removed entry will be returned. * *

If this set is empty, remove will return null without modifying the * set. Because null cannot be added, a return value of null will never * indicate a successful removal. * * @return The removed entry if the removal was successful; null otherwise */ public E remove();

/** * Removes all entries from this set. * *

If this set is already empty, clear will not modify the set. * Otherwise, the set will be modified so that it contains no entries. */ public void clear();

/** * Tests whether this set contains a given entry. Equality is determined * using the .equals() method. * *

If this set contains entry, then contains returns true. Otherwise * (including if this set is empty), contains returns false. If entry is * null, then remove throws NullPointerException. The method never modifies * this set. * * @param entry The entry to locate * @return true if this set contains entry; false if not * @throws NullPointerException If entry is null */ public boolean contains(E entry) throws NullPointerException;

/** * Retrieves all entries that are in this set. * *

An array is returned that contains a reference to each of the entries * in this set. The returned array's length will be equal to the number of * elements in this set, and thus the array will contain no null values. * *

If the implementation of set is array-backed, toArray will not return * the private backing array. Instead, a new array will be allocated with * exactly the appropriate capacity (including an array of size 0, if the * set is empty). * * @return A newly-allocated array of all the entries in this set */ public Object[] toArray();

}

2.

/** * A MovieShelf is a representation of a shelf of movies. It assumes you are * not a collector and therefore only have one copy of each movie. It also * assumes you are not very organized and don't alphabetize your movies. * It uses the Set data structure to store a collection of Movies. */ public interface MovieShelfInterface {

/** * Adds a movie to the shelf, if possible. * * @param item the movie to add * @return true if the movie was added, and false if it's already on the shelf. */ public boolean addItem(Movie item);

/** * Removes a movie from the shelf, if it exists. * * @param item the movie to remove * @return true if the movie was removed, and false if it wasn't on the shelf. */ public boolean removeItem(Movie item);

/** * Watches a movie. If a movie with the same description is on the shelf, * then its watch count is incremented, and the new watch count is returned. * If the movie is not on the shelf, this method makes no changes to the * shelf and returns -1. * * @param item the movie to watch * @return the new watch count, or -1 if the movie was not found */ public int watchMovie(Movie item);

/** * Prints all movies. Prints each item on a separate line. Each item should * show the title, year, rating, and watch count. */ public void printAll();

/** * Borrows a movie from another movie shelf, if possible. * * If the given movie is not on the other shelf, this method does not * modify either shelf and returns false. * * If the given movie is already on this shelf, this method does not * modify either shelf and returns false. * * Otherwise, it will remove the movie from the other shelf, and * add it to this shelf, and return true. * * @param other the shelf to borrow a movie from. * @param item the movie to borrow. * @return true if it was borrowed successfully, false otherwise. */ public boolean borrowMovie(MovieShelfInterface other, Movie item); }