mondrian.util
Class UnionIterator<T>

java.lang.Object
  mondrian.util.UnionIterator<T>

All Implemented Interfaces:

Iterator<T>

public class UnionIterator<T>
extends Object
implements Iterator<T>

Iterator over union of several Iterable collections.

Try, for instance, using the over(java.lang.Iterable...) helper method:

List<String> names;
List<String> addresses;
for (Sstring s : UnionIterator.over(names, addresses)) { print(s);
}

Since:

Apr 28, 2008

Author:

jhyde

Constructor Summary

UnionIterator(Collection<? extends T>... iterables)
Creates a UnionIterator over a list of collections.

UnionIterator(Iterable<? extends T>... iterables)
Creates a UnionIterator.

Method Summary

boolean	hasNext()
T	next()
static <T> Iterable<T>	over(Collection<? extends T>... collections) Returns the union of a list of collections.
static <T> Iterable<T>	over(Iterable<? extends T>... iterables) Returns the union of a list of iterables.
void	remove()

Methods inherited from class java.lang.Object

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

Constructor Detail

UnionIterator

public UnionIterator(Iterable<? extends T>... iterables)

Creates a UnionIterator.

Parameters:

iterables - Array of iterables

UnionIterator

public UnionIterator(Collection<? extends T>... iterables)

Creates a UnionIterator over a list of collections.

Parameters:

iterables - Array of collections

Method Detail

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T>

next

public T next()

Specified by:

next in interface Iterator<T>

remove

public void remove()

Specified by:

remove in interface Iterator<T>

over

public static <T> Iterable<T> over(Iterable<? extends T>... iterables)

Returns the union of a list of iterables.

You can use it like this:

 Iterable<String> iter1;
 Iterable<String> iter2;
 for (String s : union(iter1, iter2)) {
   print(s);
 }

Parameters:

iterables - Array of one or more iterables

Returns:

iterable over the union of the iterables

over

public static <T> Iterable<T> over(Collection<? extends T>... collections)

Returns the union of a list of collections.

This method exists for code that will be retrowoven to run on JDK 1.4. Retroweaver has its own version of the Iterable interface, which is problematic since the Collection classes don't implement it. This method solves some of these problems by working in terms of collections; retroweaver deals with these correctly.

Parameters:

collections - Array of one or more collections

Returns:

iterable over the union of the collections

See Also:

over(Iterable[])