com.google.common.collect.ConsumingQueueIterator Maven / Gradle / Ivy
/*
* Copyright (C) 2015 The Guava Authors
*
* 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.google.common.collect;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.GwtCompatible;
import java.util.ArrayDeque;
import java.util.Collections;
import java.util.Queue;
/**
* An Iterator implementation which draws elements from a queue, removing them from the queue as it
* iterates.
*/
@GwtCompatible
class ConsumingQueueIterator extends AbstractIterator {
private final Queue queue;
ConsumingQueueIterator(T... elements) {
this.queue = new ArrayDeque(elements.length);
Collections.addAll(queue, elements);
}
ConsumingQueueIterator(Queue queue) {
this.queue = checkNotNull(queue);
}
@Override
public T computeNext() {
return queue.isEmpty() ? endOfData() : queue.remove();
}
}