org.zkoss.util
Class DualCollection<T>

java.lang.Object
  java.util.AbstractCollection<T>
      org.zkoss.util.DualCollection<T>

All Implemented Interfaces:

Serializable, Iterable<T>, Collection<T>

public class DualCollection<T>
extends AbstractCollection<T>
implements Serializable

A combination of two collections into a collection.

Since:

3.0.0

Author:

tomyeh

See Also:

Serialized Form

Constructor Summary

DualCollection(Collection<T> first, Collection<T> second)
Constructor.

Method Summary

static <M> Collection<M>	combine(Collection<M> first, Collection<M> second) Returns a collection by combining two collections.
Iterator<T>	iterator()
int	size()

Methods inherited from class java.util.AbstractCollection

add, addAll, clear, contains, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

equals, hashCode

Constructor Detail

DualCollection

public DualCollection(Collection<T> first,
                      Collection<T> second)

Constructor. It is better to use combine(java.util.Collection, java.util.Collection) instead of this method since it checks whether any of them is null or equals.

Method Detail

combine

public static final <M> Collection<M> combine(Collection<M> first,
                                              Collection<M> second)

Returns a collection by combining two collections. It checks whether any of them is null, or equals. And, returns the non-null one if another is null. If both null, it returns null.

size

public int size()

Specified by:

size in interface Collection<T>

Specified by:

size in class AbstractCollection<T>

iterator

public Iterator<T> iterator()

Specified by:

iterator in interface Iterable<T>

Specified by:

iterator in interface Collection<T>

Specified by:

iterator in class AbstractCollection<T>