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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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.
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package java.lang.classfile.constantpool;

import java.lang.classfile.AnnotationValue;
import java.lang.constant.ConstantDesc;
import jdk.internal.javac.PreviewFeature;

/**
 * A constant pool entry that may be used by annotation constant values,
 * which includes the four kinds of primitive constants and UTF8 constants.
 * These entries are also the only entries that do not refer to other
 * constant pool entries.
 *
 * @apiNote
 * An annotation constant value entry alone is not sufficient to determine
 * the annotation constant; for example, an {@link IntegerEntry} of {@code 1}
 * can mean {@code true} in {@link AnnotationValue.OfBoolean} or {@code 1}
 * in {@link AnnotationValue.OfInt}.
 *
 * @see AnnotationValue.OfConstant
 * @sealedGraph
 * @since 22
 */
@PreviewFeature(feature = PreviewFeature.Feature.CLASSFILE_API)
public sealed interface AnnotationConstantValueEntry extends PoolEntry
        permits DoubleEntry, FloatEntry, IntegerEntry, LongEntry, Utf8Entry {

    /**
     * {@return the constant value}  The constant value will be an {@link Integer},
     * {@link Long}, {@link Float}, {@link Double} for the primitive constants,
     * or {@link String} for UTF8 constants.
     */
    ConstantDesc constantValue();
}