| /* |
| * Copyright 2000-2013 JetBrains s.r.o. |
| * |
| * 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 com.jetbrains.python.toolbox; |
| |
| import org.jetbrains.annotations.Nullable; |
| |
| import java.util.Iterator; |
| |
| /** |
| * An iterator that combines several other iterators and exhaust them one by one, in chain. |
| * User: dcheryasov |
| * Date: Nov 19, 2009 3:49:38 AM |
| */ |
| public class ChainIterator<T> extends ChainedListBase<Iterator<T>> implements Iterator<T> { |
| |
| private ChainIterationMixin<T, Iterator<T>> myMixin; |
| |
| /** |
| * Creates new instance. |
| * @param initial initial iterator. If null, the new iterator is empty, use {@link #add} to add initial content. |
| */ |
| public ChainIterator(@Nullable Iterator<T> initial) { |
| super(initial); |
| |
| myMixin = new ChainIterationMixin<T, Iterator<T>>(this) { |
| @Override |
| public Iterator<T> toIterator(Iterator<T> first) { |
| return first; |
| } |
| }; |
| } |
| |
| |
| /** |
| * Adds another iterator to the chain. Values from this iterator will follow the values of the iterator passed to the constructor. |
| * Adding after the iteration has started is safe. |
| * @param another iterator to add to the end of the chain. |
| * @return self, for easy chaining. |
| */ |
| public ChainIterator<T> add(Iterator<T> another) { |
| return (ChainIterator<T>)super.add(another); |
| } |
| |
| |
| public boolean hasNext() { |
| return myMixin.hasNext(); |
| } |
| |
| public T next() { |
| return myMixin.next(); |
| } |
| |
| public void remove() { |
| throw new UnsupportedOperationException("Cannot remove from ChainIterator"); |
| } |
| } |