com.tangosol.util
Class DeltaSet

java.lang.Object
  java.util.AbstractCollection
      java.util.AbstractSet
          com.tangosol.util.DeltaSet

All Implemented Interfaces:

Serializable, Cloneable, Iterable, Collection, Set

public class DeltaSet
extends AbstractSet
implements Cloneable, Serializable

Implements a set which is based on another set, which is assumed to be immutable.

Version:

1.00, 11/30/98

Author:

Cameron Purdy

Nested Class Summary

protected class

DeltaSet.DeltaIterator Iterator for the contents of a delta set.

Constructor Summary

DeltaSet(Set set)
Construct this set based on an existing set.

Method Summary

boolean	add(Object o) Ensures that this Collection contains the specified element.
void	clear() Removes all of the elements from this Collection.
Object	clone() Clone the delta set.
boolean	contains(Object o) Returns true if this Collection contains the specified element.
protected Set	ensureAdded() Get a mutable set of items that were added to the delta set.
protected Set	ensureRemoved() Get a mutable set of items that were removed from the delta set.
Set	getAdded() Determine what items were added to the delta set.
Set	getOriginal() Determine what items were in the original set.
Set	getRemoved() Determine what items were removed from the delta set.
boolean	isModified() Determine if any items were added or removed.
Iterator	iterator() Returns an Iterator over the elements contained in this Collection.
boolean	remove(Object o) Removes a single instance of the specified element from this Collection, if it is present (optional operation).
void	reset() Discard the changes to the set ("rollback").
void	resolve() Apply the changes to the underlying set ("commit").
int	size() Returns the number of elements in this Collection.
Object[]	toArray() Returns an array containing all of the elements in this Set.

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, isEmpty, retainAll, toArray, toString

Methods inherited from interface java.util.Set

addAll, containsAll, isEmpty, retainAll, toArray

Constructor Detail

DeltaSet

public DeltaSet(Set set)

Construct this set based on an existing set.

Parameters:

set - the set to base this delta set on

Method Detail

getOriginal

public Set getOriginal()

Determine what items were in the original set.

Returns:

the set used to construct this DeltaSet

isModified

public boolean isModified()

Determine if any items were added or removed.

Returns:

true if the set has been modified

getAdded

public Set getAdded()

Determine what items were added to the delta set.

Returns:

an immutable set of added items

getRemoved

public Set getRemoved()

Determine what items were removed from the delta set.

Returns:

an immutable set of removed items

ensureAdded

protected Set ensureAdded()

Get a mutable set of items that were added to the delta set.

Returns:

a mutable set of added items

ensureRemoved

protected Set ensureRemoved()

Get a mutable set of items that were removed from the delta set.

Returns:

a mutable set of removed items

resolve

public void resolve()

Apply the changes to the underlying set ("commit").

reset

public void reset()

Discard the changes to the set ("rollback").

iterator

public Iterator iterator()

Returns an Iterator over the elements contained in this Collection.

Specified by:

iterator in interface Iterable

Specified by:

iterator in interface Collection

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()

Returns the number of elements in this Collection.

Specified by:

size in interface Collection

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)

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

Specified by:

contains in interface Collection

Specified by:

contains in interface Set

Overrides:

contains in class AbstractCollection

Parameters:

o - the object to search for in the set

Returns:

true if this set contains the specified object

add

public boolean add(Object o)

Ensures that this Collection contains the specified element.

Specified by:

add in interface Collection

Specified by:

add in interface Set

Overrides:

add in class AbstractCollection

Parameters:

o - element whose presence in this Collection is to be ensured

Returns:

true if the Collection changed as a result of the call

remove

public boolean remove(Object o)

Removes a single instance of the specified element from this Collection, if it is present (optional operation). More formally, removes an element e such that (o==null ? e==null : o.equals(e)), if the Collection contains one or more such elements. Returns true if the Collection contained the specified element (or equivalently, if the Collection changed as a result of the call).

Specified by:

remove in interface Collection

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

clear

public void clear()

Removes all of the elements from this Collection.

Specified by:

clear in interface Collection

Specified by:

clear in interface Set

Overrides:

clear in class AbstractCollection

toArray

public Object[] toArray()

Returns an array containing all of the elements in this Set. Obeys the general contract of Collection.toArray.

Specified by:

toArray in interface Collection

Specified by:

toArray in interface Set

Overrides:

toArray in class AbstractCollection

Returns:

an Object array containing all of the elements in this Set

clone

public Object clone()

Clone the delta set.

Returns:

a clone of this delta set