java.util
Class IdentityHashMap.KeySet

java.lang.Object
  java.util.AbstractCollection
      java.util.AbstractSet
          java.util.IdentityHashMap.KeySet

All Implemented Interfaces:

Collection, Set

Enclosing class:

IdentityHashMap

private class IdentityHashMap.KeySet

extends AbstractSet

Constructor Summary

private

IdentityHashMap.KeySet()

Method Summary

void	clear() Removes all of the elements from this set (optional operation).
boolean	contains(Object o) Returns true if this set contains the specified element.
int	hashCode() Returns the hash code value for this set.
Iterator	iterator() Returns an iterator over the elements in this set.
boolean	remove(Object o) Removes the specified element from this set if it is present (optional operation).
boolean	removeAll(Collection c) Removes from this set all of its elements that are contained in the specified collection (optional operation).
int	size() Returns the number of elements in this set (its cardinality).

Methods inherited from class java.util.AbstractSet

equals

Methods inherited from class java.util.AbstractCollection

add, addAll, containsAll, isEmpty, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

add, addAll, containsAll, isEmpty, retainAll, toArray, toArray

Constructor Detail

IdentityHashMap.KeySet

private IdentityHashMap.KeySet()

Method Detail

iterator

public Iterator iterator()

Description copied from interface: Set

Returns an iterator over the elements in this set. The elements are returned in no particular order (unless this set is an instance of some class that provides a guarantee).

Specified by:

iterator in interface Set

Specified by:

iterator in class AbstractCollection

Returns:

an iterator over the elements contained in this collection.

size

public int size()

Description copied from interface: Set

Returns the number of elements in this set (its cardinality). If this set contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Specified by:

size in interface Set

Specified by:

size in class AbstractCollection

Returns:

the number of elements in this collection.

contains

public boolean contains(Object o)

Description copied from interface: Set

Returns true if this set contains the specified element. More formally, returns true if and only if this set contains an element e such that (o==null ? e==null : o.equals(e)).

Specified by:

contains in interface Set

Overrides:

contains in class AbstractCollection

Parameters:

o - object to be checked for containment in this collection.

Returns:

true if this collection contains the specified element.

remove

public boolean remove(Object o)

Description copied from interface: Set

Removes the specified element from this set if it is present (optional operation). More formally, removes an element e such that (o==null ? e==null : o.equals(e)), if the set contains such an element. Returns true if the set contained the specified element (or equivalently, if the set changed as a result of the call). (The set will not contain the specified element once the call returns.)

Specified by:

remove in interface Set

Overrides:

remove in class AbstractCollection

Parameters:

o - element to be removed from this collection, if present.

Returns:

true if the collection contained the specified element.

removeAll

public boolean removeAll(Collection c)

Description copied from class: AbstractSet

Removes from this set all of its elements that are contained in the specified collection (optional operation).

This implementation determines which is the smaller of this set and the specified collection, by invoking the size method on each. If this set has fewer elements, then the implementation iterates over this set, checking each element returned by the iterator in turn to see if it is contained in the specified collection. If it is so contained, it is removed from this set with the iterator's remove method. If the specified collection has fewer elements, then the implementation iterates over the specified collection, removing from this set each element returned by the iterator, using this set's remove method.

Note that this implementation will throw an UnsupportedOperationException if the iterator returned by the iterator method does not implement the remove method.

Specified by:

removeAll in interface Set

Overrides:

removeAll in class AbstractSet

Parameters:

c - elements to be removed from this set.

Returns:

true if this set changed as a result of the call.

See Also:

AbstractCollection.remove(Object), AbstractCollection.contains(Object)

clear

public void clear()

Description copied from interface: Set

Removes all of the elements from this set (optional operation). This set will be empty after this call returns (unless it throws an exception).

Specified by:

clear in interface Set

Overrides:

clear in class AbstractCollection

hashCode

public int hashCode()

Description copied from class: AbstractSet

Returns the hash code value for this set. The hash code of a set is defined to be the sum of the hash codes of the elements in the set. This ensures that s1.equals(s2) implies that s1.hashCode()==s2.hashCode() for any two sets s1 and s2, as required by the general contract of Object.hashCode.

This implementation enumerates over the set, calling the hashCode method on each element in the collection, and adding up the results.

Specified by:

hashCode in interface Set

Overrides:

hashCode in class AbstractSet

Returns:

the hash code value for this set.