@GwtCompatible public abstract class ForwardingSet<E> extends ForwardingCollection<E> implements Set<E>
Warning: The methods of ForwardingSet forward
indiscriminately to the methods of the delegate. For example,
overriding ForwardingCollection.add(E) alone will not change the behavior of ForwardingCollection.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 |
ForwardingSet()
Constructor for use by subclasses.
|
| Modifier and Type | Method and Description |
|---|---|
protected abstract Set<E> |
delegate()
Returns the backing delegate instance that methods are forwarded to.
|
boolean |
equals(Object object)
Indicates whether some other object is "equal to" this one.
|
int |
hashCode()
Returns a hash code value for the object.
|
protected boolean |
standardEquals(Object object)
A sensible definition of
equals(java.lang.Object) in terms of ForwardingCollection.size() and
ForwardingCollection.containsAll(java.util.Collection<?>). |
protected int |
standardHashCode()
A sensible definition of
hashCode() in terms of ForwardingCollection.iterator(). |
protected boolean |
standardRemoveAll(Collection<?> collection)
A sensible definition of
ForwardingCollection.removeAll(java.util.Collection<?>) in terms of ForwardingCollection.iterator()
and ForwardingCollection.remove(java.lang.Object). |
add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, retainAll, size, standardAddAll, standardClear, standardContains, standardContainsAll, standardIsEmpty, standardRemove, standardRetainAll, standardToArray, standardToArray, standardToString, toArray, toArraytoStringprotected ForwardingSet()
protected abstract Set<E> delegate()
ForwardingObjectdelegate(). Concrete subclasses override this method to supply
the instance being decorated.delegate in class ForwardingCollection<E>public boolean equals(@Nullable Object object)
java.lang.Object
The equals method implements an equivalence relation
on non-null object references:
x, x.equals(x) should return
true.
x and y, x.equals(y)
should return true if and only if
y.equals(x) returns true.
x, y, and z, if
x.equals(y) returns true and
y.equals(z) returns true, then
x.equals(z) should return true.
x and y, multiple invocations of
x.equals(y) consistently return true
or consistently return false, provided no
information used in equals comparisons on the
objects is modified.
x,
x.equals(null) should return false.
The equals method for class Object implements
the most discriminating possible equivalence relation on objects;
that is, for any non-null reference values x and
y, this method returns true if and only
if x and y refer to the same object
(x == y has the value true).
Note that it is generally necessary to override the hashCode
method whenever this method is overridden, so as to maintain the
general contract for the hashCode method, which states
that equal objects must have equal hash codes.
equals in interface Collection<E>equals in interface Set<E>equals in class Objectobject - the reference object with which to compare.true if this object is the same as the obj
argument; false otherwise.Object.hashCode(),
HashMappublic int hashCode()
java.lang.ObjectHashMap.
The general contract of hashCode is:
hashCode method
must consistently return the same integer, provided no information
used in equals comparisons on the object is modified.
This integer need not remain consistent from one execution of an
application to another execution of the same application.
equals(Object)
method, then calling the hashCode method on each of
the two objects must produce the same integer result.
Object.equals(java.lang.Object)
method, then calling the hashCode method on each of the
two objects must produce distinct integer results. However, the
programmer should be aware that producing distinct integer results
for unequal objects may improve the performance of hash tables.
As much as is reasonably practical, the hashCode method defined by
class Object does return distinct integers for distinct
objects. (This is typically implemented by converting the internal
address of the object into an integer, but this implementation
technique is not required by the
JavaTM programming language.)
hashCode in interface Collection<E>hashCode in interface Set<E>hashCode in class ObjectObject.equals(java.lang.Object),
System.identityHashCode(java.lang.Object)protected boolean standardRemoveAll(Collection<?> collection)
ForwardingCollection.removeAll(java.util.Collection<?>) in terms of ForwardingCollection.iterator()
and ForwardingCollection.remove(java.lang.Object). If you override iterator or remove,
you may wish to override ForwardingCollection.removeAll(java.util.Collection<?>) to forward to this
implementation.standardRemoveAll in class ForwardingCollection<E>ForwardingCollection version as of 12.0)protected boolean standardEquals(@Nullable Object object)
equals(java.lang.Object) in terms of ForwardingCollection.size() and
ForwardingCollection.containsAll(java.util.Collection<?>). If you override either of those methods, you may wish
to override equals(java.lang.Object) to forward to this implementation.protected int standardHashCode()
hashCode() in terms of ForwardingCollection.iterator().
If you override ForwardingCollection.iterator(), you may wish to override equals(java.lang.Object)
to forward to this implementation.Copyright © 2010-2013. All Rights Reserved.