/**
* Copyright (c) 2002-2011 "Neo Technology,"
* Network Engine for Objects in Lund AB [http://neotechnology.com]
*
* This file is part of Neo4j.
*
* Neo4j is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.neo4j.helpers.collection;
import java.util.Iterator;
/**
* Wraps an {@link Iterable} so that it returns items of another type. The
* iteration is done lazily.
*
* @param <T> the type of items to return
* @param <U> the type of items to wrap/convert from
*/
public abstract class IterableWrapper<T, U> implements Iterable<T>
{
private Iterable<U> source;
public IterableWrapper( Iterable<U> iterableToWrap )
{
this.source = iterableToWrap;
}
protected abstract T underlyingObjectToObject( U object );
public Iterator<T> iterator()
{
return new MyIteratorWrapper( source.iterator() );
}
private class MyIteratorWrapper extends IteratorWrapper<T, U>
{
public MyIteratorWrapper( Iterator<U> iteratorToWrap )
{
super( iteratorToWrap );
}
@Override
protected T underlyingObjectToObject( U object )
{
return IterableWrapper.this.underlyingObjectToObject( object );
}
}
}