com.artemis.utils

Class Bag<E>

java.lang.Object

com.artemis.utils.Bag<E>

Type Parameters:

E - object type this bag holds

All Implemented Interfaces:

ImmutableBag<E>, Iterable<E>

public class Bag<E>
extends Object
implements ImmutableBag<E>

Collection type a bit like ArrayList but does not preserve the order of its entities, speedwise it is very good, especially suited for games.

Author:

Arni Arent

Field Summary

Fields

Modifier and Type	Field and Description
protected int	size The amount of elements contained in bag.

Constructor Summary

Constructors

Constructor and Description
Bag() Constructs an empty Bag with an initial capacity of 64.
Bag(int capacity) Constructs an empty Bag with the specified initial capacity.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(E e) Adds the specified element to the end of this bag.
void	addAll(ImmutableBag<E> items) Add all items into this bag.
void	clear() Removes all of the elements from this bag.
boolean	contains(E e) Check if bag contains this element.
void	ensureCapacity(int index) Check if an item, if added at the given item will fit into the bag.
void	fastClear() Removes all of the elements from this by re-allocating the backing array.
E	get(int index) Returns the element at the specified position in Bag.
int	getCapacity() Returns the number of elements the bag can hold without growing.
Object[]	getData() Returns this bag's underlying array.
boolean	isEmpty() Returns true if this bag contains no elements.
boolean	isIndexWithinBounds(int index) Checks if the internal storage supports this index.
Iterator<E>	iterator()
boolean	remove(E e) Removes the first occurrence of the specified element from this Bag, if it is present.
E	remove(int index) Removes the element at the specified position in this Bag.
boolean	removeAll(ImmutableBag<E> bag) Removes from this Bag all of its elements that are contained in the specified Bag.
E	removeLast() Remove and return the last object in the bag.
E	safeGet(int index) Returns the element at the specified position in Bag.
void	set(int index, E e) Set element at specified index in the bag.
int	size() Returns the number of elements in this bag.
void	sort(Comparator<E> comparator) Sorts the bag using the comparator.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

size

protected int size

The amount of elements contained in bag.

Constructor Detail

Bag

public Bag()

Constructs an empty Bag with an initial capacity of 64.

Bag

public Bag(int capacity)

Constructs an empty Bag with the specified initial capacity.

Parameters:

capacity - the initial capacity of Bag

Method Detail

remove

public E remove(int index)
         throws ArrayIndexOutOfBoundsException

Removes the element at the specified position in this Bag.

It does this by overwriting it was last element then removing last element

Parameters:

index - the index of element to be removed

Returns:

element that was removed from the Bag

Throws:

ArrayIndexOutOfBoundsException

sort

public void sort(Comparator<E> comparator)

Sorts the bag using the comparator.

Parameters:

comparator -

removeLast

public E removeLast()

Remove and return the last object in the bag.

Returns:

the last object in the bag, null if empty

remove

public boolean remove(E e)

Removes the first occurrence of the specified element from this Bag, if it is present.

If the Bag does not contain the element, it is unchanged. It does this by overwriting it was last element then removing last element

Parameters:

e - element to be removed from this list, if present

Returns:

true if this list contained the specified element

contains

public boolean contains(E e)

Check if bag contains this element.

Specified by:

contains in interface ImmutableBag<E>

Parameters:

e - element to check

Returns:

true if the bag contains this element

removeAll

public boolean removeAll(ImmutableBag<E> bag)

Removes from this Bag all of its elements that are contained in the specified Bag.

Parameters:

bag - Bag containing elements to be removed from this Bag

Returns:

true if this Bag changed as a result of the call

get

public E get(int index)
      throws ArrayIndexOutOfBoundsException

Returns the element at the specified position in Bag.

Specified by:

get in interface ImmutableBag<E>

Parameters:

index - index of the element to return

Returns:

the element at the specified position in bag

Throws:

ArrayIndexOutOfBoundsException

safeGet

public E safeGet(int index)

Returns the element at the specified position in Bag. This method ensures that the bag grows if the requested index is outside the bounds of the current backing array.

Parameters:

index - index of the element to return

Returns:

the element at the specified position in bag

size

public int size()

Returns the number of elements in this bag.

Specified by:

size in interface ImmutableBag<E>

Returns:

the number of elements in this bag

getCapacity

public int getCapacity()

Returns the number of elements the bag can hold without growing.

Returns:

the number of elements the bag can hold without growing

isIndexWithinBounds

public boolean isIndexWithinBounds(int index)

Checks if the internal storage supports this index.

Parameters:

index - index to check

Returns:

true if the index is within bounds

isEmpty

public boolean isEmpty()

Returns true if this bag contains no elements.

Specified by:

isEmpty in interface ImmutableBag<E>

Returns:

true if this bag contains no elements

add

public void add(E e)

Adds the specified element to the end of this bag.

If required, it also increases the capacity of the bag.

Parameters:

e - element to be added to this list

set

public void set(int index,
       E e)

Set element at specified index in the bag.

Parameters:

index - position of element

e - the element

ensureCapacity

public void ensureCapacity(int index)

Check if an item, if added at the given item will fit into the bag.

If not, the bag capacity will be increased to hold an item at the index.

Parameters:

index - index to check

clear

public void clear()

Removes all of the elements from this bag.

The bag will be empty after this call returns.

fastClear

public void fastClear()

Removes all of the elements from this by re-allocating the backing array.

The bag will be empty after this call returns.

addAll

public void addAll(ImmutableBag<E> items)

Add all items into this bag.

Parameters:

items - bag with items to add

getData

public Object[] getData()

Returns this bag's underlying array.

Use with care.

Returns:

the underlying array

See Also:

size()

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

toString

public String toString()

Overrides:

toString in class Object