android.support.v4.util

Class CircularArray<E>

java.lang.Object

android.support.v4.util.CircularArray<E>

public final class CircularArray<E>
extends Object

CircularArray is a generic circular array data structure that provides O(1) random read, O(1) prepend and O(1) append. The CircularArray automatically grows its capacity when number of added items is over its capacity.

Constructor Summary

Constructors

Constructor and Description
CircularArray() Create a CircularArray with default capacity.
CircularArray(int minCapacity) Create a CircularArray with capacity for at least minCapacity elements.

Method Summary

Modifier and Type	Method and Description
void	addFirst(E e) Add an element in front of the CircularArray.
void	addLast(E e) Add an element at end of the CircularArray.
void	clear() Remove all elements from the CircularArray.
E	get(int n) Get nth (0 <= n <= size()-1) element of the CircularArray.
E	getFirst() Get first element of the CircularArray.
E	getLast() Get last element of the CircularArray.
boolean	isEmpty() Return true if size() is 0.
E	popFirst() Remove first element from front of the CircularArray and return it.
E	popLast() Remove last element from end of the CircularArray and return it.
void	removeFromEnd(int numOfElements) Remove multiple elements from end of the CircularArray, ignore when numOfElements is less than or equals to 0.
void	removeFromStart(int numOfElements) Remove multiple elements from front of the CircularArray, ignore when numOfElements is less than or equals to 0.
int	size() Get number of elements in the CircularArray.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CircularArray

public CircularArray()

Create a CircularArray with default capacity.

CircularArray

public CircularArray(int minCapacity)

Create a CircularArray with capacity for at least minCapacity elements.

Parameters:

minCapacity - The minimum capacity required for the CircularArray.

Method Detail

addFirst

public void addFirst(E e)

Add an element in front of the CircularArray.

Parameters:

e - Element to add.

addLast

public void addLast(E e)

Add an element at end of the CircularArray.

Parameters:

e - Element to add.

popFirst

public E popFirst()

Remove first element from front of the CircularArray and return it.

Returns:

The element removed.

Throws:

ArrayIndexOutOfBoundsException - if CircularArray is empty.

popLast

public E popLast()

Remove last element from end of the CircularArray and return it.

Returns:

The element removed.

Throws:

ArrayIndexOutOfBoundsException - if CircularArray is empty.

clear

public void clear()

Remove all elements from the CircularArray.

removeFromStart

public void removeFromStart(int numOfElements)

Remove multiple elements from front of the CircularArray, ignore when numOfElements is less than or equals to 0.

Parameters:

numOfElements - Number of elements to remove.

Throws:

ArrayIndexOutOfBoundsException - if numOfElements is larger than size()

removeFromEnd

public void removeFromEnd(int numOfElements)

Remove multiple elements from end of the CircularArray, ignore when numOfElements is less than or equals to 0.

Parameters:

numOfElements - Number of elements to remove.

Throws:

ArrayIndexOutOfBoundsException - if numOfElements is larger than size()

getFirst

public E getFirst()

Get first element of the CircularArray.

Returns:

The first element.

Throws:

{@link - ArrayIndexOutOfBoundsException} if CircularArray is empty.

getLast

public E getLast()

Get last element of the CircularArray.

Returns:

The last element.

Throws:

{@link - ArrayIndexOutOfBoundsException} if CircularArray is empty.

get

public E get(int n)

Get nth (0 <= n <= size()-1) element of the CircularArray.

Parameters:

n - The zero based element index in the CircularArray.

Returns:

The nth element.

Throws:

{@link - ArrayIndexOutOfBoundsException} if n < 0 or n >= size().

size

public int size()

Get number of elements in the CircularArray.

Returns:

Number of elements in the CircularArray.

isEmpty

public boolean isEmpty()

Return true if size() is 0.

Returns:

true if size() is 0.