| /* | |
| * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. | |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
| * | |
| * This code is free software; you can redistribute it and/or modify it | |
| * under the terms of the GNU General Public License version 2 only, as | |
| * published by the Free Software Foundation. Oracle designates this | |
| * particular file as subject to the "Classpath" exception as provided | |
| * by Oracle in the LICENSE file that accompanied this code. | |
| * | |
| * This code is distributed in the hope that it will be useful, but WITHOUT | |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| * version 2 for more details (a copy is included in the LICENSE file that | |
| * accompanied this code). | |
| * | |
| * You should have received a copy of the GNU General Public License version | |
| * 2 along with this work; if not, write to the Free Software Foundation, | |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| * | |
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| */ | |
| package java.util; | |
| /** | |
| * Marker interface used by {@code List} implementations to indicate that | |
| * they support fast (generally constant time) random access. The primary | |
| * purpose of this interface is to allow generic algorithms to alter their | |
| * behavior to provide good performance when applied to either random or | |
| * sequential access lists. | |
| * | |
| * <p>The best algorithms for manipulating random access lists (such as | |
| * {@code ArrayList}) can produce quadratic behavior when applied to | |
| * sequential access lists (such as {@code LinkedList}). Generic list | |
| * algorithms are encouraged to check whether the given list is an | |
| * {@code instanceof} this interface before applying an algorithm that would | |
| * provide poor performance if it were applied to a sequential access list, | |
| * and to alter their behavior if necessary to guarantee acceptable | |
| * performance. | |
| * | |
| * <p>It is recognized that the distinction between random and sequential | |
| * access is often fuzzy. For example, some {@code List} implementations | |
| * provide asymptotically linear access times if they get huge, but constant | |
| * access times in practice. Such a {@code List} implementation | |
| * should generally implement this interface. As a rule of thumb, a | |
| * {@code List} implementation should implement this interface if, | |
| * for typical instances of the class, this loop: | |
| * <pre> | |
| * for (int i=0, n=list.size(); i < n; i++) | |
| * list.get(i); | |
| * </pre> | |
| * runs faster than this loop: | |
| * <pre> | |
| * for (Iterator i=list.iterator(); i.hasNext(); ) | |
| * i.next(); | |
| * </pre> | |
| * | |
| * <p>This interface is a member of the | |
| * <a href="{@docRoot}/java.base/java/util/package-summary.html#CollectionsFramework"> | |
| * Java Collections Framework</a>. | |
| * | |
| * @since 1.4 | |
| */ | |
| public interface RandomAccess { | |
| } |