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.
default method warning: This class does not forward calls to default methods. Instead, it inherits their default implementations. When those implementations
invoke methods, they invoke methods on the ForwardingCollection.
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) |
toStringclone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, waitprotected ForwardingCollection()
protected abstract java.util.Collection<E> delegate()
ForwardingObjectForwardingSet.delegate(). Concrete subclasses override this method to supply the
instance being decorated.delegate in class ForwardingObjectpublic 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(@CheckForNull
java.lang.Object object)
contains in interface java.util.Collection<E>public boolean remove(@CheckForNull
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>protected boolean standardContains(@CheckForNull
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.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.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.protected boolean standardRemove(@CheckForNull
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.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.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.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.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.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.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.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.