DualCollection (zk 10.0.0 API)

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

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<T>, java.util.Collection<T>
```
public class DualCollection<T>
extends java.util.AbstractCollection<T>
implements java.io.Serializable
```
A combination of two collections into a collection.

Since:

3.0.0

Author:

tomyeh

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor Description

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

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static <M> java.util.Collection<M>`	`combine(java.util.Collection<M> first, java.util.Collection<M> second)`	Returns a collection by combining two collections.
`java.util.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, parallelStream, removeIf, spliterator, stream, toArray

Methods inherited from interface java.lang.Iterable
forEach

- Constructor Detail
  - DualCollection
```
public DualCollection(java.util.Collection<T> first,
                      java.util.Collection<T> second)
```
    Constructor. It is better to use combine(java.util.Collection<M>, java.util.Collection<M>) instead of this method since it checks whether any of them is null or equals.
- Method Detail
  - combine
```
public static final <M> java.util.Collection<M> combine(java.util.Collection<M> first,
                                                        java.util.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 java.util.Collection<T>
    
    Specified by:
    
    size in class java.util.AbstractCollection<T>
  - iterator
```
public java.util.Iterator<T> iterator()
```
    Specified by:
    
    iterator in interface java.util.Collection<T>
    
    Specified by:
    
    iterator in interface java.lang.Iterable<T>
    
    Specified by:
    
    iterator in class java.util.AbstractCollection<T>