001/*
002 * ModeShape (http://www.modeshape.org)
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *       http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.modeshape.schematic.annotation;
017
018import java.lang.annotation.Documented;
019import java.lang.annotation.ElementType;
020import java.lang.annotation.Retention;
021import java.lang.annotation.RetentionPolicy;
022import java.lang.annotation.Target;
023
024/**
025 * Copyright (c) 2005 Brian Goetz and Tim Peierls.<br />
026 * Released under the Creative Commons Attribution License<br />
027 * (http://creativecommons.org/licenses/by/2.5)<br />
028 * Official home: http://www.jcip.net<br />
029 * Adopted from Java Concurrency in Practice.
030 * <p>
031 * This annotation documents that instances of the annotated class are immutable. This means that its state is seen to others as
032 * never being changed, even though the actual private internal state may indeed change. Therefore, in an immutable class:
033 * <ul>
034 * <li>all public fields are final; and</li>
035 * <li>all public final reference fields refer to other immutable objects; and</li>
036 * <li>constructors and methods do not publish references to any internal state which is potentially mutable by the
037 * implementation.</li>
038 * </ul>
039 * </p>
040 */
041@Documented
042@Target( ElementType.TYPE )
043@Retention( RetentionPolicy.RUNTIME )
044public @interface Immutable {
045}