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/*
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 * 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).
 *
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 * 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 io.github.dmlloyd.classfile.attribute;

import java.lang.constant.ClassDesc;
import java.util.Arrays;
import java.util.List;

import io.github.dmlloyd.classfile.Attribute;
import io.github.dmlloyd.classfile.ClassElement;
import io.github.dmlloyd.classfile.constantpool.ClassEntry;
import io.github.dmlloyd.classfile.impl.BoundAttribute;
import io.github.dmlloyd.classfile.impl.UnboundAttribute;
import io.github.dmlloyd.classfile.impl.Util;
import io.github.dmlloyd.classfile.extras.PreviewFeature;

/**
 * Models the {@code PermittedSubclasses} attribute (JVMS {@jvms 4.7.31}), which can
 * appear on classes to indicate which classes may extend this class.
 * Delivered as a {@link io.github.dmlloyd.classfile.ClassElement} when
 * traversing the elements of a {@link io.github.dmlloyd.classfile.ClassModel}.
 * 
 * The attribute does not permit multiple instances in a given location.
 * Subsequent occurrence of the attribute takes precedence during the attributed
 * element build or transformation.
 * 
 * The attribute was introduced in the Java SE Platform version 17.
 *
 * @since 22
 */
@PreviewFeature(feature = PreviewFeature.Feature.CLASSFILE_API)
public sealed interface PermittedSubclassesAttribute
        extends Attribute, ClassElement
        permits BoundAttribute.BoundPermittedSubclassesAttribute, UnboundAttribute.UnboundPermittedSubclassesAttribute {

    /**
     * {@return the list of permitted subclasses}
     */
    List permittedSubclasses();

    /**
     * {@return a {@code PermittedSubclasses} attribute}
     * @param permittedSubclasses the permitted subclasses
     */
    static PermittedSubclassesAttribute of(List permittedSubclasses) {
        return new UnboundAttribute.UnboundPermittedSubclassesAttribute(permittedSubclasses);
    }

    /**
     * {@return a {@code PermittedSubclasses} attribute}
     * @param permittedSubclasses the permitted subclasses
     */
    static PermittedSubclassesAttribute of(ClassEntry... permittedSubclasses) {
        return of(List.of(permittedSubclasses));
    }

    /**
     * {@return a {@code PermittedSubclasses} attribute}
     * @param permittedSubclasses the permitted subclasses
     */
    static PermittedSubclassesAttribute ofSymbols(List permittedSubclasses) {
        return of(Util.entryList(permittedSubclasses));
    }

    /**
     * {@return a {@code PermittedSubclasses} attribute}
     * @param permittedSubclasses the permitted subclasses
     */
    static PermittedSubclassesAttribute ofSymbols(ClassDesc... permittedSubclasses) {
        // List view, since ref to nestMembers is temporary
        return ofSymbols(Arrays.asList(permittedSubclasses));
    }
}