/* | |
* Licensed to the Apache Software Foundation (ASF) under one | |
* or more contributor license agreements. See the NOTICE file | |
* distributed with this work for additional information | |
* regarding copyright ownership. The ASF licenses this file | |
* to you 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.apache.myfaces.buildtools.maven2.plugin.builder.trinidad.util; | |
import java.util.Iterator; | |
import java.util.NoSuchElementException; | |
/** | |
* CompoundIterator consumes the initial iterator before | |
* observing the next iterator. | |
*/ | |
public class CompoundIterator implements Iterator | |
{ | |
public CompoundIterator( | |
Iterator primary, | |
Iterator secondary) | |
{ | |
this(new Iterator[] {primary, secondary}); | |
} | |
public CompoundIterator( | |
Iterator[] iterators) | |
{ | |
_iterators = iterators; | |
_index = 0; | |
_advance(); | |
} | |
public boolean hasNext() | |
{ | |
return (_next != null); | |
} | |
public Object next() | |
{ | |
if (_next == null) | |
throw new NoSuchElementException(); | |
Object obj = _next; | |
_advance(); | |
return obj; | |
} | |
public void remove() | |
{ | |
throw new UnsupportedOperationException(); | |
} | |
private void _advance() | |
{ | |
Iterator current = _iterators[_index]; | |
if (current != null && !current.hasNext()) | |
{ | |
_index ++; | |
current = (_index < _iterators.length) ? _iterators[_index] : null; | |
} | |
_next = (current != null && current.hasNext()) ? current.next() : null; | |
} | |
private Object _next; | |
private Iterator[] _iterators; | |
private int _index; | |
} |