Class SynchronizedCollection<E>

java.lang.Object

org.apache.commons.collections4.collection.SynchronizedCollection<E>

Type Parameters:

E - the type of the elements in the collection

All Implemented Interfaces:

Serializable, Iterable<E>, Collection<E>

Direct Known Subclasses:

SynchronizedBag, SynchronizedMultiSet, SynchronizedQueue

public class SynchronizedCollection<E>
extends Object
implements Collection<E>, Serializable

Decorates another Collection to synchronize its behaviour for a multi-threaded environment.

Iterators must be manually synchronized:

synchronized (coll) {
  Iterator it = coll.iterator();
  // do stuff with iterator
}

This class is Serializable from Commons Collections 3.1.

Since:

3.0

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected final Object	lock	The object to lock on, needed for List/SortedSet views

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SynchronizedCollection(Collection<E> collection)	Constructor that wraps (not copies).
protected	SynchronizedCollection(Collection<E> collection, Object lock)	Constructor that wraps (not copies).

Method Summary

Modifier and Type	Method	Description
boolean	add(E object)
boolean	addAll(Collection<? extends E> coll)
void	clear()
boolean	contains(Object object)
boolean	containsAll(Collection<?> coll)
protected Collection<E>	decorated()	Gets the collection being decorated.
boolean	equals(Object object)
int	hashCode()
boolean	isEmpty()
Iterator<E>	iterator()	Iterators must be manually synchronized.
boolean	remove(Object object)
boolean	removeAll(Collection<?> coll)
boolean	removeIf(Predicate<? super E> filter)
boolean	retainAll(Collection<?> coll)
int	size()
static <T> SynchronizedCollection<T>	synchronizedCollection(Collection<T> coll)	Factory method to create a synchronized collection.
Object[]	toArray()
<T> T[]	toArray(T[] object)
String	toString()

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface Collection

parallelStream, spliterator, stream, toArray

Methods inherited from interface Iterable

forEach

Field Details

lock

protected final Object lock

The object to lock on, needed for List/SortedSet views

Constructor Details

SynchronizedCollection

protected SynchronizedCollection(Collection<E> collection)

Constructor that wraps (not copies).

Parameters:

collection - the collection to decorate, must not be null

Throws:

NullPointerException - if the collection is null

SynchronizedCollection

protected SynchronizedCollection(Collection<E> collection,
 Object lock)

Constructor that wraps (not copies).

Parameters:

collection - the collection to decorate, must not be null

lock - the lock object to use, must not be null

Throws:

NullPointerException - if the collection or lock is null

Method Details

synchronizedCollection

public static <T> SynchronizedCollection<T> synchronizedCollection(Collection<T> coll)

Factory method to create a synchronized collection.

Type Parameters:

T - the type of the elements in the collection

Parameters:

coll - the collection to decorate, must not be null

Returns:

a new synchronized collection

Throws:

NullPointerException - if collection is null

Since:

4.0

decorated

protected Collection<E> decorated()

Gets the collection being decorated.

Returns:

the decorated collection

add

public boolean add(E object)

Specified by:

add in interface Collection<E>

addAll

public boolean addAll(Collection<? extends E> coll)

Specified by:

addAll in interface Collection<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

contains

public boolean contains(Object object)

Specified by:

contains in interface Collection<E>

containsAll

public boolean containsAll(Collection<?> coll)

Specified by:

containsAll in interface Collection<E>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<E>

iterator

public Iterator<E> iterator()

Iterators must be manually synchronized.

synchronized (coll) {
  Iterator it = coll.iterator();
  // do stuff with iterator
}

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Iterable<E>

Returns:

an iterator that must be manually synchronized on the collection

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection<E>

toArray

public <T> T[] toArray(T[] object)

Specified by:

toArray in interface Collection<E>

remove

public boolean remove(Object object)

Specified by:

remove in interface Collection<E>

removeIf

public boolean removeIf(Predicate<? super E> filter)

Specified by:

removeIf in interface Collection<E>

Since:

4.4

removeAll

public boolean removeAll(Collection<?> coll)

Specified by:

removeAll in interface Collection<E>

retainAll

public boolean retainAll(Collection<?> coll)

Specified by:

retainAll in interface Collection<E>

size

public int size()

Specified by:

size in interface Collection<E>

equals

public boolean equals(Object object)

Specified by:

equals in interface Collection<E>

Overrides:

equals in class Object

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<E>

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object