Package net.automatalib.common.smartcollection

Class UnorderedCollection<E>

java.lang.Object

java.util.AbstractCollection<E>

net.automatalib.common.smartcollection.AbstractSmartCollection<E>

net.automatalib.common.smartcollection.UnorderedCollection<E>

Type Parameters:

E - element class.

All Implemented Interfaces:

Iterable<E>, Collection<E>, CapacityManagement, SmartCollection<E>

public final class UnorderedCollection<E>
extends AbstractSmartCollection<E>
implements CapacityManagement

This class implements a collection for storing objects in no particular order.

It supports (amortized) constant time insertion and removal. Removal does not invalidate the references of other objects, and can be performed during iteration (using the respective Iterator.remove() method).

Constructor Summary

Constructors

Constructor	Description
UnorderedCollection()	Default constructor.
UnorderedCollection(int initialCapacity)	Constructor.
UnorderedCollection(Collection<? extends E> coll)	Constructor.

Method Summary

Modifier and Type	Method	Description
boolean	addAll(Collection<? extends E> coll)
<T extends E> void	addAll(T[] array)	Adds all elements from the specified array.
E	choose()	Retrieves an arbitrary element from the collection.
ElementReference	chooseRef()	Retrieves the reference to an arbitrary element from the collection.
void	clear()
void	deepClear()	Thoroughly clears the collection, fixing all issues that may have been caused by a call of the above SmartCollection.quickClear().
boolean	ensureAdditionalCapacity(int additionalSpace)	Ensures that the internal storage has room for at least the provided number of additional elements.
boolean	ensureCapacity(int minCapacity)	Ensures that the internal storage has room for at least the provided number of elements.
E	get(ElementReference ref)	Retrieves an element by its reference.
void	hintNextCapacity(int nextCapacityHint)	Gives a hint regarding the capacity that should be reserved when resizing the internal storage for the next time.
boolean	isEmpty()
Iterator<E>	iterator()
void	quickClear()	Quickly clears this collection.
ElementReference	referencedAdd(E elem)	Adds an element to the collection, returning a reference to the newly added element.
Iterator<ElementReference>	referenceIterator()	Retrieves an iterator for iterating over the references of elements in this collection.
Iterable<ElementReference>	references()	This is a method provided for convenience, which allows iterating over the element references using a foreach-style for-loop.
void	remove(ElementReference ref)	Removes an element (by its reference) from the collection.
void	replace(ElementReference ref, E newElement)	Replaces the element referenced by the given reference with the specified element.
int	size()
void	swap(UnorderedCollection<E> other)	Swaps the contents of this UnorderedCollection with another one storing the same elements.

Methods inherited from class net.automatalib.common.smartcollection.AbstractSmartCollection

add, addAll, find, remove

Methods inherited from class java.util.AbstractCollection

contains, containsAll, removeAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

contains, containsAll, equals, hashCode, parallelStream, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

UnorderedCollection

public UnorderedCollection()

Default constructor. Reserves capacity for 10 elements.

UnorderedCollection

public UnorderedCollection(int initialCapacity)

Constructor. Reserves the specified initial capacity.

Parameters:

initialCapacity - the number of elements to reserve capacity for.

UnorderedCollection

public UnorderedCollection(Collection<? extends E> coll)

Constructor. Initializes the collection with the contents of the specified collection.

Parameters:

coll - the collection.

Method Detail

ensureCapacity

public boolean ensureCapacity(@UnknownInitialization(UnorderedCollection.class) UnorderedCollection<E> this,
                              int minCapacity)

Description copied from interface: CapacityManagement

Ensures that the internal storage has room for at least the provided number of elements.

Specified by:

ensureCapacity in interface CapacityManagement

Parameters:

minCapacity - the minimal number of elements the storage should have room for.

Returns:

true iff the internal storage had to be resized, false otherwise.

ensureAdditionalCapacity

public boolean ensureAdditionalCapacity(int additionalSpace)

Description copied from interface: CapacityManagement

Ensures that the internal storage has room for at least the provided number of additional elements.

Calling this method is equivalent to calling the above CapacityManagement.ensureCapacity(int) with an argument of size() + additionalCapacity.

Specified by:

ensureAdditionalCapacity in interface CapacityManagement

Parameters:

additionalSpace - the number of additional elements the storage should have room for.

Returns:

true iff the internal storage had to be resized, false otherwise.

hintNextCapacity

public void hintNextCapacity(int nextCapacityHint)

Description copied from interface: CapacityManagement

Gives a hint regarding the capacity that should be reserved when resizing the internal storage for the next time. This method acts like a "lazy" CapacityManagement.ensureCapacity(int), i.e. it reserves the specified capacity at the time the next resizing of the internal storage is performed.

This method is useful when a not too imprecise upper bound on the elements that will in consequence be added is known. Since the actual number of elements added may be lower than the specified upper bound, a resizing that would have been performed by CapacityManagement.ensureCapacity(int) might not be necessary.

Specified by:

hintNextCapacity in interface CapacityManagement

Parameters:

nextCapacityHint - the next capacity hint.

get

public E get(ElementReference ref)

Description copied from interface: SmartCollection

Retrieves an element by its reference.

If the reference belongs to another collection, the behavior is undefined.

Specified by:

get in interface SmartCollection<E>

Parameters:

ref - the element's reference.

Returns:

the element.

referencedAdd

public ElementReference referencedAdd(E elem)

Description copied from interface: SmartCollection

Adds an element to the collection, returning a reference to the newly added element. If the collection does not support containing the same element multiple times, a reference to the previously existing element is returned.

Specified by:

referencedAdd in interface SmartCollection<E>

Parameters:

elem - the element to be added.

Returns:

a reference to this element in the collection.

remove

public void remove(ElementReference ref)

Description copied from interface: SmartCollection

Removes an element (by its reference) from the collection.

If the reference does not belong to this collection, the behavior is undefined.

Specified by:

remove in interface SmartCollection<E>

Parameters:

ref - the reference to the element to be removed.

referenceIterator

public Iterator<ElementReference> referenceIterator()

Description copied from interface: SmartCollection

Retrieves an iterator for iterating over the references of elements in this collection.

Specified by:

referenceIterator in interface SmartCollection<E>

Returns:

the reference iterator.

replace

public void replace(ElementReference ref,
                    E newElement)

Description copied from interface: SmartCollection

Replaces the element referenced by the given reference with the specified element.

Specified by:

replace in interface SmartCollection<E>

Parameters:

ref - the reference of the element to be replaced.

newElement - the replacement.

choose

public E choose()

Description copied from interface: SmartCollection

Retrieves an arbitrary element from the collection.

Specified by:

choose in interface SmartCollection<E>

Overrides:

choose in class AbstractSmartCollection<E>

Returns:

an arbitrary element from the collection

chooseRef

public ElementReference chooseRef()

Description copied from interface: SmartCollection

Retrieves the reference to an arbitrary element from the collection. If the collection is empty, a NoSuchElementException is thrown.

Specified by:

chooseRef in interface SmartCollection<E>

Overrides:

chooseRef in class AbstractSmartCollection<E>

Returns:

the reference to an arbitrary element in the collection

references

public Iterable<ElementReference> references()

Description copied from interface: SmartCollection

This is a method provided for convenience, which allows iterating over the element references using a foreach-style for-loop.

Specified by:

references in interface SmartCollection<E>

Overrides:

references in class AbstractSmartCollection<E>

Returns:

an Iterable with the above SmartCollection.referenceIterator() as its iterator.

addAll

public <T extends E> void addAll(T[] array)

Description copied from interface: SmartCollection

Adds all elements from the specified array.

Specified by:

addAll in interface SmartCollection<E>

Overrides:

addAll in class AbstractSmartCollection<E>

Type Parameters:

T - array element class, may be a subclass of E.

Parameters:

array - the array of elements to be added.

addAll

public boolean addAll(@UnknownInitialization(UnorderedCollection.class) UnorderedCollection<E> this,
                      Collection<? extends E> coll)

Specified by:

addAll in interface Collection<E>

Overrides:

addAll in class AbstractCollection<E>

quickClear

public void quickClear()

Description copied from interface: SmartCollection

Quickly clears this collection. This method is supposed to perform the minimum amount of effort such that this collection is emptied, disregarding all other side effects such as referencing or garbage collection issues.

Depending on the implementation, this may be just the same as Collection.clear(). However, this could also have side effects like hampering the garbage collection or such.

After calling this method, even a call of the normal Collection.clear() is not guaranteed to fix all these issues. This can only be achieved by the method SmartCollection.deepClear() below.

Specified by:

quickClear in interface SmartCollection<E>

Overrides:

quickClear in class AbstractSmartCollection<E>

deepClear

public void deepClear()

Description copied from interface: SmartCollection

Thoroughly clears the collection, fixing all issues that may have been caused by a call of the above SmartCollection.quickClear().

Specified by:

deepClear in interface SmartCollection<E>

Overrides:

deepClear in class AbstractSmartCollection<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Iterable<E>

Overrides:

iterator in class AbstractSmartCollection<E>

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in class AbstractCollection<E>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<E>

Overrides:

isEmpty in class AbstractCollection<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Overrides:

clear in class AbstractCollection<E>

swap

public void swap(UnorderedCollection<E> other)

Swaps the contents of this UnorderedCollection with another one storing the same elements. This operation runs in constant time, by only swapping storage references.

Parameters:

other - the UnorderedCollection to swap contents with.