/*

 * Copyright (c) 2019, 2020, 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.internal.javac;

import java.lang.annotation.*;

/**

 * Indicates the API declaration in question is associated with a

 * <em>preview feature</em>. See JEP 12: "Preview Language and VM

 * Features" (http://openjdk.java.net/jeps/12).

 *

 * Note this internal annotation is handled specially by the javac compiler.

 * To work properly with {@code --release older-release}, it requires special

 * handling in {@code make/langtools/src/classes/build/tools/symbolgenerator/CreateSymbols.java}

 * and {@code src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/ClassReader.java}.

 *

 * @since 14

 */

// Match the meaningful targets of java.lang.Deprecated, omit local

// variables and parameter declarations

@Target({ElementType.METHOD,

         ElementType.CONSTRUCTOR,

         ElementType.FIELD,

         ElementType.PACKAGE,

         ElementType.MODULE,

         ElementType.TYPE})

 // CLASS retention will hopefully be sufficient for the purposes at hand

@Retention(RetentionPolicy.CLASS)

// *Not* @Documented

public @interface PreviewFeature {

    /**

     * Name of the preview feature the annotated API is associated

     * with.

     */

    public Feature feature();

    public boolean reflective() default false;

    public enum Feature {

        /*

         * This one can only be removed after JDK 17

         */

        SEALED_CLASSES,

        SWITCH_PATTERN_MATCHING,

        /**

         * A key for testing.

         */

        TEST,

        ;

    }

}