src/java.base/share/classes/java/lang/foreign/GroupLayout.java

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package java.lang.foreign;

import java.util.List;

/**
 * A compound layout that is an aggregation of multiple, heterogeneous
 * <em>member layouts</em>. There are two ways in which member layouts can be combined:
 * if member layouts are laid out one after the other, the resulting group layout is a
 * {@linkplain StructLayout struct layout}; conversely, if all member layouts are laid
 * out at the same starting offset, the resulting group layout is a
 * {@linkplain UnionLayout union layout}.
 *
 * @implSpec
 * This class is immutable, thread-safe and
 * <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>.
 *
 * @sealedGraph
 * @since 22
 */
public sealed interface GroupLayout extends MemoryLayout permits StructLayout, UnionLayout {

    /**
     * {@return the member layouts of this group layout}
     *
     * @apiNote the order in which member layouts are returned is the same order in which
     *          member layouts have been passed to one of the group layout factory methods
     *          (see {@link MemoryLayout#structLayout(MemoryLayout...)} and
     *          {@link MemoryLayout#unionLayout(MemoryLayout...)}).
     */
    List<MemoryLayout> memberLayouts();

    /**
     * {@inheritDoc}
     */
    @Override
    GroupLayout withName(String name);

    /**
     * {@inheritDoc}
     */
    @Override
    GroupLayout withoutName();

    /**
     * {@inheritDoc}
     * @throws IllegalArgumentException {@inheritDoc}
     * @throws IllegalArgumentException if {@code byteAlignment} is less than {@code M},
     *         where {@code M} is the maximum alignment constraint in any of the
     *         member layouts associated with this group layout
     */
    @Override
    GroupLayout withByteAlignment(long byteAlignment);
}