1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.collections.primitives;
18
19 /**
20 * An iterator over <code>double</code> values.
21 *
22 * @see org.apache.commons.collections.primitives.adapters.DoubleIteratorIterator
23 * @see org.apache.commons.collections.primitives.adapters.IteratorDoubleIterator
24 *
25 * @since Commons Primitives 1.0
26 * @version $Revision: 480460 $ $Date: 2006-11-29 03:14:21 -0500 (Wed, 29 Nov 2006) $
27 *
28 * @author Rodney Waldhoff
29 */
30 public interface DoubleIterator {
31 /**
32 * Returns <code>true</code> iff I have more elements.
33 * (In other words, returns <code>true</code> iff
34 * a subsequent call to {@link #next next} will return
35 * an element rather than throwing an exception.)
36 *
37 * @return <code>true</code> iff I have more elements
38 */
39 boolean hasNext();
40
41 /**
42 * Returns the next element in me.
43 *
44 * @return the next element in me
45 * @throws java.util.NoSuchElementException if there is no next element
46 */
47 double next();
48
49 /**
50 * Removes from my underlying collection the last
51 * element {@link #next returned} by me
52 * (optional operation).
53 *
54 * @throws UnsupportedOperationException if this operation is not supported
55 * @throws IllegalStateException if {@link #next} has not yet been
56 * called, or {@link #remove} has already been called since
57 * the last call to {@link #next}.
58 */
59 void remove();
60 }