@GwtCompatible public abstract class ForwardingCollection<E> extends ForwardingObject implements java.util.Collection<E>
Warning: The methods of ForwardingCollection
forward
indiscriminately to the methods of the delegate. For example,
overriding add(E)
alone will not change the behavior of addAll(java.util.Collection<? extends E>)
, which can lead to unexpected behavior. In this case, you should
override addAll
as well, either providing your own implementation, or
delegating to the provided standardAddAll
method.
The standard
methods are not guaranteed to be thread-safe, even
when all of the methods that they depend on are thread-safe.
Modifier | Constructor and Description |
---|---|
protected |
ForwardingCollection()
Constructor for use by subclasses.
|
Modifier and Type | Method and Description |
---|---|
boolean |
add(E element) |
boolean |
addAll(java.util.Collection<? extends E> collection) |
void |
clear() |
boolean |
contains(java.lang.Object object) |
boolean |
containsAll(java.util.Collection<?> collection) |
protected abstract java.util.Collection<E> |
delegate()
Returns the backing delegate instance that methods are forwarded to.
|
boolean |
isEmpty() |
java.util.Iterator<E> |
iterator() |
boolean |
remove(java.lang.Object object) |
boolean |
removeAll(java.util.Collection<?> collection) |
boolean |
retainAll(java.util.Collection<?> collection) |
int |
size() |
protected boolean |
standardAddAll(java.util.Collection<? extends E> collection)
A sensible definition of
addAll(java.util.Collection<? extends E>) in terms of add(E) . |
protected void |
standardClear()
|
protected boolean |
standardContains(java.lang.Object object)
A sensible definition of
contains(java.lang.Object) in terms of iterator() . |
protected boolean |
standardContainsAll(java.util.Collection<?> collection)
A sensible definition of
containsAll(java.util.Collection<?>) in terms of contains(java.lang.Object)
. |
protected boolean |
standardIsEmpty()
A sensible definition of
isEmpty() as !iterator().hasNext . |
protected boolean |
standardRemove(java.lang.Object object)
A sensible definition of
remove(java.lang.Object) in terms of iterator() ,
using the iterator's remove method. |
protected boolean |
standardRemoveAll(java.util.Collection<?> collection)
A sensible definition of
removeAll(java.util.Collection<?>) in terms of iterator() ,
using the iterator's remove method. |
protected boolean |
standardRetainAll(java.util.Collection<?> collection)
A sensible definition of
retainAll(java.util.Collection<?>) in terms of iterator() ,
using the iterator's remove method. |
protected java.lang.Object[] |
standardToArray()
A sensible definition of
toArray() in terms of toArray(Object[]) . |
protected <T> T[] |
standardToArray(T[] array)
|
protected java.lang.String |
standardToString()
A sensible definition of
ForwardingObject.toString() in terms of iterator() . |
java.lang.Object[] |
toArray() |
<T> T[] |
toArray(T[] array) |
toString
protected ForwardingCollection()
protected abstract java.util.Collection<E> delegate()
ForwardingObject
ForwardingSet.delegate()
. Concrete subclasses override this method to supply
the instance being decorated.delegate
in class ForwardingObject
public java.util.Iterator<E> iterator()
public int size()
size
in interface java.util.Collection<E>
public boolean removeAll(java.util.Collection<?> collection)
removeAll
in interface java.util.Collection<E>
public boolean isEmpty()
isEmpty
in interface java.util.Collection<E>
public boolean contains(java.lang.Object object)
contains
in interface java.util.Collection<E>
public boolean remove(java.lang.Object object)
remove
in interface java.util.Collection<E>
public boolean containsAll(java.util.Collection<?> collection)
containsAll
in interface java.util.Collection<E>
public boolean addAll(java.util.Collection<? extends E> collection)
addAll
in interface java.util.Collection<E>
public boolean retainAll(java.util.Collection<?> collection)
retainAll
in interface java.util.Collection<E>
public void clear()
clear
in interface java.util.Collection<E>
public java.lang.Object[] toArray()
toArray
in interface java.util.Collection<E>
public <T> T[] toArray(T[] array)
toArray
in interface java.util.Collection<E>
@Beta protected boolean standardContains(@Nullable java.lang.Object object)
contains(java.lang.Object)
in terms of iterator()
.
If you override iterator()
, you may wish to override contains(java.lang.Object)
to forward to this implementation.@Beta protected boolean standardContainsAll(java.util.Collection<?> collection)
containsAll(java.util.Collection<?>)
in terms of contains(java.lang.Object)
. If you override contains(java.lang.Object)
, you may wish to override containsAll(java.util.Collection<?>)
to forward to this implementation.@Beta protected boolean standardAddAll(java.util.Collection<? extends E> collection)
addAll(java.util.Collection<? extends E>)
in terms of add(E)
. If you
override add(E)
, you may wish to override addAll(java.util.Collection<? extends E>)
to forward
to this implementation.@Beta protected boolean standardRemove(@Nullable java.lang.Object object)
remove(java.lang.Object)
in terms of iterator()
,
using the iterator's remove
method. If you override iterator()
, you may wish to override remove(java.lang.Object)
to forward to this
implementation.@Beta protected boolean standardRemoveAll(java.util.Collection<?> collection)
removeAll(java.util.Collection<?>)
in terms of iterator()
,
using the iterator's remove
method. If you override iterator()
, you may wish to override removeAll(java.util.Collection<?>)
to forward to this
implementation.@Beta protected boolean standardRetainAll(java.util.Collection<?> collection)
retainAll(java.util.Collection<?>)
in terms of iterator()
,
using the iterator's remove
method. If you override iterator()
, you may wish to override retainAll(java.util.Collection<?>)
to forward to this
implementation.@Beta protected void standardClear()
clear()
in terms of iterator()
,
using the iterator's remove
method. If you override iterator()
, you may wish to override clear()
to forward to this
implementation.@Beta protected boolean standardIsEmpty()
isEmpty()
as !iterator().hasNext
.
If you override isEmpty()
, you may wish to override isEmpty()
to forward to this implementation. Alternately, it may be more efficient to
implement isEmpty
as size() == 0
.@Beta protected java.lang.String standardToString()
ForwardingObject.toString()
in terms of iterator()
.
If you override iterator()
, you may wish to override ForwardingObject.toString()
to forward to this implementation.@Beta protected java.lang.Object[] standardToArray()
toArray()
in terms of toArray(Object[])
. If you override toArray(Object[])
, you may
wish to override toArray()
to forward to this implementation.@Beta protected <T> T[] standardToArray(T[] array)
toArray(Object[])
in terms of size()
and iterator()
. If you override either of these methods, you
may wish to override toArray()
to forward to this implementation.