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/*
 * Copyright (c) 2012-2024, jcabi.com
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met: 1) Redistributions of source code must retain the above
 * copyright notice, this list of conditions and the following
 * disclaimer. 2) Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided
 * with the distribution. 3) Neither the name of the jcabi.com nor
 * the names of its contributors may be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.jcabi.aspects;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Annotates an immutable class.
 *
 * For example:
 *
 * 
 @Immutable
 * public class Foo {
 *   private String data;
 * }
 *
 * As soon as you try to instantiate this class a runtime exception
 * will be thrown, because this class is mutable.
 *
 * @since 0.7.8
 * @see http://aspects.jcabi.com/
 * @see Objects Should Be Immutable, by Yegor Bugayenko
 */
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface Immutable {
    /**
     * Identifies that an array-type field should be considered immutable. Note
     * that for an array to be considered immutable, its component type must
     * also be immutable.
     * @since 0.17
     * @todo #33 Let's prevent modifications to arrays having this annotation,
     *  somehow. Perhaps we can create an aspect that will throw an exception
     *  should something try to write into the array. See
     *  https://bugs.eclipse.org/bugs/show_bug.cgi?id=157031
     */
    @Documented
    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.FIELD)
    @interface Array {
    }
}