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An unofficial backport of the JDK Classfile API to Java 17

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/*
 * Copyright (c) 2022, 2024, 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
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 */

package io.github.dmlloyd.classfile.attribute;

import io.github.dmlloyd.classfile.Attribute;
import io.github.dmlloyd.classfile.CodeModel;
import io.github.dmlloyd.classfile.Label;

import io.github.dmlloyd.classfile.impl.BoundAttribute;

/**
 * Models the {@code Code} attribute (JVMS {@jvms 4.7.3}), appears on non-native,
 * non-abstract methods and contains the bytecode of the method body.  Delivered
 * as a {@link io.github.dmlloyd.classfile.MethodElement} when traversing the elements of a
 * {@link io.github.dmlloyd.classfile.MethodModel}.
 * 
 * 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.
 *
 * @since 24
 */
public sealed interface CodeAttribute extends Attribute, CodeModel
        permits BoundAttribute.BoundCodeAttribute {

    /**
     * {@return the maximum size of the local variable table}
     */
    int maxLocals();

    /**
     * {@return the maximum size of the operand stack}
     */
    int maxStack();

    /**
     * {@return The length of the code array in bytes}
     */
    int codeLength();

    /**
     * {@return the bytes (bytecode) of the code array}
     */
    byte[] codeArray();

    /**
     * {@return the position of the {@code label} in the {@link #codeArray codeArray}}
     * @param label a marker for a position within this {@code CodeAttribute}
     * @throws IllegalArgumentException if the {@code label} is not from this attribute
     */
    int labelToBci(Label label);
}