1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
26 package java.util;
27
28 import java.util.function.Consumer;
29
30 /**
31 * An iterator over a collection. {@code Iterator} takes the place of
32 * {@link Enumeration} in the Java Collections Framework. Iterators
33 * differ from enumerations in two ways:
34 *
35 * <ul>
36 * <li> Iterators allow the caller to remove elements from the
37 * underlying collection during the iteration with well-defined
38 * semantics.
39 * <li> Method names have been improved.
40 * </ul>
41 *
42 * <p>This interface is a member of the
43 * <a href="{@docRoot}/../technotes/guides/collections/index.html">
44 * Java Collections Framework</a>.
45 *
46 * @param <E> the type of elements returned by this iterator
47 *
48 * @author Josh Bloch
49 * @see Collection
50 * @see ListIterator
51 * @see Iterable
52 * @since 1.2
53 */
54 public interface Iterator<E> {
55 /**
56 * Returns {@code true} if the iteration has more elements.
57 * (In other words, returns {@code true} if {@link #next} would
58 * return an element rather than throwing an exception.)
59 *
60 * @return {@code true} if the iteration has more elements
61 */
62 boolean hasNext();
63
64 /**
65 * Returns the next element in the iteration.
|
1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
26 package java.util;
27
28 import java.util.function.Consumer;
29
30 /**
31 * An iterator over a collection. {@code Iterator} takes the place of
32 * {@link Enumeration} in the Java Collections Framework. Iterators
33 * differ from enumerations in two ways:
34 *
35 * <ul>
36 * <li> Iterators allow the caller to remove elements from the
37 * underlying collection during the iteration with well-defined
38 * semantics.
39 * <li> Method names have been improved.
40 * </ul>
41 *
42 * <p>This interface is a member of the
43 * <a href="{@docRoot}/../technotes/guides/collections/index.html">
44 * Java Collections Framework</a>.
45 *
46 * @apiNote
47 * An {@link Enumeration} can be converted into an {@code Iterator} by
48 * using the {@link Enumeration#asIterator} method.
49 *
50 * @param <E> the type of elements returned by this iterator
51 *
52 * @author Josh Bloch
53 * @see Collection
54 * @see ListIterator
55 * @see Iterable
56 * @since 1.2
57 */
58 public interface Iterator<E> {
59 /**
60 * Returns {@code true} if the iteration has more elements.
61 * (In other words, returns {@code true} if {@link #next} would
62 * return an element rather than throwing an exception.)
63 *
64 * @return {@code true} if the iteration has more elements
65 */
66 boolean hasNext();
67
68 /**
69 * Returns the next element in the iteration.
|