bag

Interface BagInterface<T>

All Known Implementing Classes:

Bag

public interface BagInterface<T>

An interface that describes the operations of a bag of objects.

Version:

4.1

Author:

Frank M. Carrano, Timothy M. Henry

Method Summary

Modifier and Type	Method and Description
boolean	add(T newEntry) Adds a new entry to this bag.
void	clear() Removes all entries from this bag.
boolean	contains(T anEntry) Tests whether this bag contains a given entry.
int	getCurrentSize() Gets the current number of entries in this bag.
int	getFrequencyOf(T anEntry) Counts the number of times a given entry appears in this bag.
boolean	isEmpty() Sees whether this bag is empty.
T	remove() Removes one unspecified entry from this bag, if possible.
boolean	remove(T anEntry) Removes one occurrence of a given entry from this bag.
T[]	toArray() Retrieves all entries that are in this bag.

Method Detail

getCurrentSize

int getCurrentSize()

Gets the current number of entries in this bag.

Returns:

The integer number of entries currently in the bag.

isEmpty

boolean isEmpty()

Sees whether this bag is empty.

Returns:

True if the bag is empty, or false if not.

add

boolean add(T newEntry)

Adds a new entry to this bag.

Parameters:

newEntry - The object to be added as a new entry.

Returns:

True if the addition is successful, or false if not.

remove

T remove()

Removes one unspecified entry from this bag, if possible.

Returns:

Either the removed entry, if the removal. was successful, or null.

remove

boolean remove(T anEntry)

Removes one occurrence of a given entry from this bag.

Parameters:

anEntry - The entry to be removed.

Returns:

True if the removal was successful, or false if not.

clear

void clear()

Removes all entries from this bag.

getFrequencyOf

int getFrequencyOf(T anEntry)

Counts the number of times a given entry appears in this bag.

Parameters:

anEntry - The entry to be counted.

Returns:

The number of times anEntry appears in the bag.

contains

boolean contains(T anEntry)

Tests whether this bag contains a given entry.

Parameters:

anEntry - The entry to locate.

Returns:

True if the bag contains anEntry, or false if not.

toArray

T[] toArray()

Retrieves all entries that are in this bag.

Returns:

A newly allocated array of all the entries in the bag. Note: If the bag is empty, the returned array is empty.