Coverage Summary for Class: ConsumingQueueIterator (com.google.common.collect)

1 /*
2  * Copyright (C) 2015 The Guava Authors
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5  * in compliance with the License. You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software distributed under the License
10  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11  * or implied. See the License for the specific language governing permissions and limitations under
12  * the License.
13  */
14 
15 package com.google.common.collect;
16 
17 import static com.google.common.base.Preconditions.checkNotNull;
18 
19 import com.google.common.annotations.GwtCompatible;
20 import java.util.ArrayDeque;
21 import java.util.Collections;
22 import java.util.Queue;
23 
24 /**
25  * An Iterator implementation which draws elements from a queue, removing them from the queue as it
26  * iterates.
27  */
28 @GwtCompatible
29 class ConsumingQueueIterator<T> extends AbstractIterator<T> {
30   private final Queue<T> queue;
31 
32   ConsumingQueueIterator(T... elements) {
33     this.queue = new ArrayDeque<T>(elements.length);
34     Collections.addAll(queue, elements);
35   }
36 
37   ConsumingQueueIterator(Queue<T> queue) {
38     this.queue = checkNotNull(queue);
39   }
40 
41   @Override
42   public T computeNext() {
43     return queue.isEmpty() ? endOfData() : queue.remove();
44   }
45 }