com.blogspot.mydailyjava.weaklockfree

Class WeakConcurrentSet<V>

java.lang.Object

com.blogspot.mydailyjava.weaklockfree.WeakConcurrentSet<V>

All Implemented Interfaces:

Iterable<V>, Runnable

public class WeakConcurrentSet<V>
extends Object
implements Runnable, Iterable<V>

A thread-safe set with weak values. Entries are based on a key's system hash code and keys are considered equal only by reference equality.

This class does not implement the Set interface because this implementation is incompatible with the set contract. While iterating over a set's entries, any value that has not passed iteration is referenced non-weakly.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	WeakConcurrentSet.Cleaner Determines the cleaning format.

Constructor Summary

Constructors

Constructor and Description
WeakConcurrentSet(WeakConcurrentSet.Cleaner cleaner)

Method Summary

Modifier and Type	Method and Description
boolean	add(V value)
int	approximateSize() Returns the approximate size of this set where the returned number is at least as big as the actual number of entries.
void	clear() Clears the set.
boolean	contains(V value)
void	expungeStaleEntries() Cleans all unused references.
Thread	getCleanerThread()
Iterator<V>	iterator()
boolean	remove(V value)
void	run()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

WeakConcurrentSet

public WeakConcurrentSet(WeakConcurrentSet.Cleaner cleaner)

Method Detail

add

public boolean add(V value)

Parameters:

value - The value to add to the set.

Returns:

true if the value was added to the set and was not contained before.

contains

public boolean contains(V value)

Parameters:

value - The value to check if it is contained in the set.

Returns:

true if the set contains the value.

remove

public boolean remove(V value)

Parameters:

value - The value to remove from the set.

Returns:

true if the value is contained in the set.

clear

public void clear()

Clears the set.

approximateSize

public int approximateSize()

Returns the approximate size of this set where the returned number is at least as big as the actual number of entries.

Returns:

The minimum size of this set.

run

public void run()

Specified by:

run in interface Runnable

expungeStaleEntries

public void expungeStaleEntries()

Cleans all unused references.

getCleanerThread

public Thread getCleanerThread()

Returns:

The cleaner thread or null if no such thread was set.

iterator

public Iterator<V> iterator()

Specified by:

iterator in interface Iterable<V>