Package io.deephaven.util.datastructures

Class SimpleReferenceManager<T,R extends SimpleReference<T>>

java.lang.Object

io.deephaven.util.datastructures.SimpleReferenceManager<T,R>

public final class SimpleReferenceManager<T,R extends SimpleReference<T>>
extends Object

A helper for managing a list of References. It hides the internal management of expired references and provides for iteration over the valid ones

Constructor Summary

Constructors

Constructor	Description
SimpleReferenceManager(@NotNull Function<T,R> referenceFactory)	Create a SimpleReferenceManager, with CopyOnWriteArrayList as backing structure.
SimpleReferenceManager(@NotNull Function<T,R> referenceFactory, boolean concurrent)	Create a SimpleReferenceManager, with either ArrayList or CopyOnWriteArrayList as backing structure.
SimpleReferenceManager(@NotNull Function<T,R> referenceFactory, @NotNull Collection<R> referenceCollection)	Create a SimpleReferenceManager with the specified referenceCollection as the backing data structure..

Method Summary

Modifier and Type	Method	Description
R	add(T item)	Add the specified item to the list.
void	clear()	Clear the list of references.
void	forEach(@NotNull BiConsumer<R,T> consumer)	Execute the provided procedure on each reference, item pair whose item is still reachable, while removing any cleared references.
T	getFirstItem(@NotNull Predicate<T> filter)	Retrieve the first valid item that satisfies a filter.
R	getFirstReference(@NotNull Predicate<T> filter)	Retrieve the first valid reference whose item satisfies a filter.
boolean	isEmpty()	Return true if the list is empty.
T	remove(T item)	Remove item from the list if present according to reference equality (==), and also any cleared references.
void	removeAll(@NotNull Collection<T> items)	Remove items in the collection from the list, and also any cleared references.
boolean	removeIf(@NotNull Predicate<T> filter)	Retrieve all encountered items that satisfy a filter, while also removing any cleared references.
int	size()	Return the number of valid references in the list.

Methods inherited from class java.lang.Object

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

Constructor Details

SimpleReferenceManager

public SimpleReferenceManager(@NotNull
 @NotNull Function<T,R> referenceFactory)

Create a SimpleReferenceManager, with CopyOnWriteArrayList as backing structure.

Parameters:

referenceFactory - Factory to create references for added referents; should always make a unique reference

SimpleReferenceManager

public SimpleReferenceManager(@NotNull
 @NotNull Function<T,R> referenceFactory,
 boolean concurrent)

Create a SimpleReferenceManager, with either ArrayList or CopyOnWriteArrayList as backing structure.

Parameters:

referenceFactory - Factory to create references for added referents; should always make a unique reference

concurrent - Use CopyOnWriteArrayList for internal storage if true, else ArrayList

SimpleReferenceManager

public SimpleReferenceManager(@NotNull
 @NotNull Function<T,R> referenceFactory,
 @NotNull
 @NotNull Collection<R> referenceCollection)

Create a SimpleReferenceManager with the specified referenceCollection as the backing data structure..

Parameters:

referenceFactory - Factory to create references for added referents; should always make a unique reference

referenceCollection - The collection to use for holding references

Method Details

add

public R add(@NotNull
 T item)

Add the specified item to the list.

Parameters:

item - the item to add.

remove

public T remove(@NotNull
 T item)

Remove item from the list if present according to reference equality (==), and also any cleared references.

Parameters:

item - the item to remove.

Returns:

The item if it was removed, else null

removeAll

public void removeAll(@NotNull
 @NotNull Collection<T> items)

Remove items in the collection from the list, and also any cleared references.

Parameters:

items - the items to remove.

removeIf

public boolean removeIf(@NotNull
 @NotNull Predicate<T> filter)

Retrieve all encountered items that satisfy a filter, while also removing any cleared references.

Parameters:

filter - The filter to decide if a valid item should be removed

Returns:

Whether we succeeded in removing anything

forEach

public void forEach(@NotNull
 @NotNull BiConsumer<R,T> consumer)

Execute the provided procedure on each reference, item pair whose item is still reachable, while removing any cleared references.

Parameters:

consumer - The function to call with each reachable pair

getFirstItem

public T getFirstItem(@NotNull
 @NotNull Predicate<T> filter)

Retrieve the first valid item that satisfies a filter. Remove any encountered cleared references as a side effect.

Parameters:

filter - The filter to decide if a valid item should be returned

Returns:

The first valid item that passed the filter, or null if no such item exists

getFirstReference

public R getFirstReference(@NotNull
 @NotNull Predicate<T> filter)

Retrieve the first valid reference whose item satisfies a filter. Remove any encountered cleared references as a side effect.

Parameters:

filter - The filter to decide if a valid item should be returned

Returns:

The first valid item that passed the filter, or null if no such item exists

isEmpty

public boolean isEmpty()

Return true if the list is empty. Does not check for cleared references.

Returns:

true if the list is empty.

size

public int size()

Return the number of valid references in the list. Note that each reference is checked for validity, making this operation linear in the number of references.

Returns:

the number of valid references in the list

clear

public void clear()

Clear the list of references.