Class UnmodifiableCollection<E>

java.lang.Object

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

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

Type Parameters:

E - the type of the elements in the collection

All Implemented Interfaces:

Serializable, Iterable<E>, Collection<E>, Unmodifiable

public final class UnmodifiableCollection<E>
extends AbstractCollectionDecorator<E>
implements Unmodifiable

Decorates another Collection to ensure it can't be altered.

This class is Serializable from Commons Collections 3.1.

Attempts to modify it will result in an UnsupportedOperationException.

Since:

3.0

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private static final long	serialVersionUID	Serialization version

Constructor Summary

Constructors

Modifier	Constructor	Description
private	UnmodifiableCollection(Collection<? extends E> coll)	Constructor that wraps (not copies).

Method Summary

Modifier and Type	Method	Description
boolean	add(E object)
boolean	addAll(Collection<? extends E> coll)
void	clear()
Iterator<E>	iterator()
boolean	remove(Object object)
boolean	removeAll(Collection<?> coll)
boolean	removeIf(Predicate<? super E> filter)
boolean	retainAll(Collection<?> coll)
static <T> Collection<T>	unmodifiableCollection(Collection<? extends T> coll)	Factory method to create an unmodifiable collection.

Methods inherited from class AbstractCollectionDecorator

contains, containsAll, decorated, isEmpty, setCollection, size, toArray, toArray, toString

Methods inherited from class Object

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

Methods inherited from interface Collection

equals, hashCode, parallelStream, spliterator, stream

Methods inherited from interface Iterable

forEach

Field Details

serialVersionUID

private static final long serialVersionUID

Serialization version

See Also:

• Constant Field Values

Constructor Details

UnmodifiableCollection

private UnmodifiableCollection(Collection<? extends E> coll)

Constructor that wraps (not copies).

Parameters:

coll - the collection to decorate, must not be null

Throws:

NullPointerException - if collection is null

Method Details

unmodifiableCollection

public static <T> Collection<T> unmodifiableCollection(Collection<? extends T> coll)

Factory method to create an unmodifiable collection.

If the collection passed in is already unmodifiable, it is returned.

Type Parameters:

T - the type of the elements in the collection

Parameters:

coll - the collection to decorate, must not be null

Returns:

an unmodifiable collection

Throws:

NullPointerException - if collection is null

Since:

4.0

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Iterable<E>

Overrides:

iterator in class AbstractCollectionDecorator<E>

add

public boolean add(E object)

Specified by:

add in interface Collection<E>

Overrides:

add in class AbstractCollectionDecorator<E>

addAll

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

Specified by:

addAll in interface Collection<E>

Overrides:

addAll in class AbstractCollectionDecorator<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Overrides:

clear in class AbstractCollectionDecorator<E>

remove

public boolean remove(Object object)

Specified by:

remove in interface Collection<E>

Overrides:

remove in class AbstractCollectionDecorator<E>

removeIf

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

Specified by:

removeIf in interface Collection<E>

Overrides:

removeIf in class AbstractCollectionDecorator<E>

Since:

4.4

removeAll

public boolean removeAll(Collection<?> coll)

Specified by:

removeAll in interface Collection<E>

Overrides:

removeAll in class AbstractCollectionDecorator<E>

retainAll

public boolean retainAll(Collection<?> coll)

Specified by:

retainAll in interface Collection<E>

Overrides:

retainAll in class AbstractCollectionDecorator<E>