/*
* Copyright (c) 2012,2013 Big Switch Networks, Inc.
*
* Licensed under the Eclipse Public License, Version 1.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.eclipse.org/legal/epl-v10.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied. See the License for the specific language governing
* permissions and limitations under the License.
*
* This file incorporates work covered by the following copyright and
* permission notice:
*
* Originally created by David Erickson, Stanford University
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an "AS
* IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language
* governing permissions and limitations under the License.
*/
package org.sdnplatform.util;
import java.util.Iterator;
import java.util.NoSuchElementException;
/**
* Iterator over all values in an iterator of iterators
*
* @param <T> the type of elements returned by this iterator
*/
public class MultiIterator<T> implements Iterator<T> {
Iterator<Iterator<T>> subIterator;
Iterator<T> current = null;
public MultiIterator(Iterator<Iterator<T>> subIterator) {
super();
this.subIterator = subIterator;
}
@Override
public boolean hasNext() {
if (current == null) {
if (subIterator.hasNext()) {
current = subIterator.next();
} else {
return false;
}
}
while (!current.hasNext() && subIterator.hasNext()) {
current = subIterator.next();
}
return current.hasNext();
}
@Override
public T next() {
if (hasNext())
return current.next();
throw new NoSuchElementException();
}
@Override
public void remove() {
if (hasNext())
current.remove();
throw new NoSuchElementException();
}
}