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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).
 *
 * 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.
 */
/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package jdk.internal.org.objectweb.asm;
/**
 * An entry of the constant pool, of the BootstrapMethods attribute, or of the (ASM specific) type
 * table of a class.
 *
 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.4">JVMS
 *     4.4</a>
 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.23">JVMS
 *     4.7.23</a>
 * @author Eric Bruneton
 */
abstract class Symbol {
    // Tag values for the constant pool entries (using the same order as in the JVMS).
    /** The tag value of CONSTANT_Class_info JVMS structures. */
    static final int CONSTANT_CLASS_TAG = 7;
    /** The tag value of CONSTANT_Fieldref_info JVMS structures. */
    static final int CONSTANT_FIELDREF_TAG = 9;
    /** The tag value of CONSTANT_Methodref_info JVMS structures. */
    static final int CONSTANT_METHODREF_TAG = 10;
    /** The tag value of CONSTANT_InterfaceMethodref_info JVMS structures. */
    static final int CONSTANT_INTERFACE_METHODREF_TAG = 11;
    /** The tag value of CONSTANT_String_info JVMS structures. */
    static final int CONSTANT_STRING_TAG = 8;
    /** The tag value of CONSTANT_Integer_info JVMS structures. */
    static final int CONSTANT_INTEGER_TAG = 3;
    /** The tag value of CONSTANT_Float_info JVMS structures. */
    static final int CONSTANT_FLOAT_TAG = 4;
    /** The tag value of CONSTANT_Long_info JVMS structures. */
    static final int CONSTANT_LONG_TAG = 5;
    /** The tag value of CONSTANT_Double_info JVMS structures. */
    static final int CONSTANT_DOUBLE_TAG = 6;
    /** The tag value of CONSTANT_NameAndType_info JVMS structures. */
    static final int CONSTANT_NAME_AND_TYPE_TAG = 12;
    /** The tag value of CONSTANT_Utf8_info JVMS structures. */
    static final int CONSTANT_UTF8_TAG = 1;
    /** The tag value of CONSTANT_MethodHandle_info JVMS structures. */
    static final int CONSTANT_METHOD_HANDLE_TAG = 15;
    /** The tag value of CONSTANT_MethodType_info JVMS structures. */
    static final int CONSTANT_METHOD_TYPE_TAG = 16;
    /** The tag value of CONSTANT_Dynamic_info JVMS structures. */
    static final int CONSTANT_DYNAMIC_TAG = 17;
    /** The tag value of CONSTANT_InvokeDynamic_info JVMS structures. */
    static final int CONSTANT_INVOKE_DYNAMIC_TAG = 18;
    /** The tag value of CONSTANT_Module_info JVMS structures. */
    static final int CONSTANT_MODULE_TAG = 19;
    /** The tag value of CONSTANT_Package_info JVMS structures. */
    static final int CONSTANT_PACKAGE_TAG = 20;
    // Tag values for the BootstrapMethods attribute entries (ASM specific tag).
    /** The tag value of the BootstrapMethods attribute entries. */
    static final int BOOTSTRAP_METHOD_TAG = 64;
    // Tag values for the type table entries (ASM specific tags).
    /** The tag value of a normal type entry in the (ASM specific) type table of a class. */
    static final int TYPE_TAG = 128;
    /**
      * The tag value of an {@link Frame#ITEM_UNINITIALIZED} type entry in the type table of a class.
      */
    static final int UNINITIALIZED_TYPE_TAG = 129;
    /** The tag value of a merged type entry in the (ASM specific) type table of a class. */
    static final int MERGED_TYPE_TAG = 130;
    // Instance fields.
    /**
      * The index of this symbol in the constant pool, in the BootstrapMethods attribute, or in the
      * (ASM specific) type table of a class (depending on the {@link #tag} value).
      */
    final int index;
    /**
      * A tag indicating the type of this symbol. Must be one of the static tag values defined in this
      * class.
      */
    final int tag;
    /**
      * The internal name of the owner class of this symbol. Only used for {@link
      * #CONSTANT_FIELDREF_TAG}, {@link #CONSTANT_METHODREF_TAG}, {@link
      * #CONSTANT_INTERFACE_METHODREF_TAG}, and {@link #CONSTANT_METHOD_HANDLE_TAG} symbols.
      */
    final String owner;
    /**
      * The name of the class field or method corresponding to this symbol. Only used for {@link
      * #CONSTANT_FIELDREF_TAG}, {@link #CONSTANT_METHODREF_TAG}, {@link
      * #CONSTANT_INTERFACE_METHODREF_TAG}, {@link #CONSTANT_NAME_AND_TYPE_TAG}, {@link
      * #CONSTANT_METHOD_HANDLE_TAG}, {@link #CONSTANT_DYNAMIC_TAG} and {@link
      * #CONSTANT_INVOKE_DYNAMIC_TAG} symbols.
      */
    final String name;
    /**
      * The string value of this symbol. This is:
      *
      * <ul>
      *   <li>a field or method descriptor for {@link #CONSTANT_FIELDREF_TAG}, {@link
      *       #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG}, {@link
      *       #CONSTANT_NAME_AND_TYPE_TAG}, {@link #CONSTANT_METHOD_HANDLE_TAG}, {@link
      *       #CONSTANT_METHOD_TYPE_TAG}, {@link #CONSTANT_DYNAMIC_TAG} and {@link
      *       #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
      *   <li>an arbitrary string for {@link #CONSTANT_UTF8_TAG} and {@link #CONSTANT_STRING_TAG}
      *       symbols,
      *   <li>an internal class name for {@link #CONSTANT_CLASS_TAG}, {@link #TYPE_TAG} and {@link
      *       #UNINITIALIZED_TYPE_TAG} symbols,
      *   <li>{@literal null} for the other types of symbol.
      * </ul>
      */
    final String value;
    /**
      * The numeric value of this symbol. This is:
      *
      * <ul>
      *   <li>the symbol's value for {@link #CONSTANT_INTEGER_TAG},{@link #CONSTANT_FLOAT_TAG}, {@link
      *       #CONSTANT_LONG_TAG}, {@link #CONSTANT_DOUBLE_TAG},
      *   <li>the CONSTANT_MethodHandle_info reference_kind field value for {@link
      *       #CONSTANT_METHOD_HANDLE_TAG} symbols,
      *   <li>the CONSTANT_InvokeDynamic_info bootstrap_method_attr_index field value for {@link
      *       #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
      *   <li>the offset of a bootstrap method in the BootstrapMethods boostrap_methods array, for
      *       {@link #CONSTANT_DYNAMIC_TAG} or {@link #BOOTSTRAP_METHOD_TAG} symbols,
      *   <li>the bytecode offset of the NEW instruction that created an {@link
      *       Frame#ITEM_UNINITIALIZED} type for {@link #UNINITIALIZED_TYPE_TAG} symbols,
      *   <li>the indices (in the class' type table) of two {@link #TYPE_TAG} source types for {@link
      *       #MERGED_TYPE_TAG} symbols,
      *   <li>0 for the other types of symbol.
      * </ul>
      */
    final long data;
    /**
      * Additional information about this symbol, generally computed lazily. <i>Warning: the value of
      * this field is ignored when comparing Symbol instances</i> (to avoid duplicate entries in a
      * SymbolTable). Therefore, this field should only contain data that can be computed from the
      * other fields of this class. It contains:
      *
      * <ul>
      *   <li>the {@link Type#getArgumentsAndReturnSizes} of the symbol's method descriptor for {@link
      *       #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG} and {@link
      *       #CONSTANT_INVOKE_DYNAMIC_TAG} symbols,
      *   <li>the index in the InnerClasses_attribute 'classes' array (plus one) corresponding to this
      *       class, for {@link #CONSTANT_CLASS_TAG} symbols,
      *   <li>the index (in the class' type table) of the merged type of the two source types for
      *       {@link #MERGED_TYPE_TAG} symbols,
      *   <li>0 for the other types of symbol, or if this field has not been computed yet.
      * </ul>
      */
    int info;
    /**
      * Constructs a new Symbol. This constructor can't be used directly because the Symbol class is
      * abstract. Instead, use the factory methods of the {@link SymbolTable} class.
      *
      * @param index the symbol index in the constant pool, in the BootstrapMethods attribute, or in
      *     the (ASM specific) type table of a class (depending on 'tag').
      * @param tag the symbol type. Must be one of the static tag values defined in this class.
      * @param owner The internal name of the symbol's owner class. Maybe {@literal null}.
      * @param name The name of the symbol's corresponding class field or method. Maybe {@literal
      *     null}.
      * @param value The string value of this symbol. Maybe {@literal null}.
      * @param data The numeric value of this symbol.
      */
    Symbol(
            final int index,
            final int tag,
            final String owner,
            final String name,
            final String value,
            final long data) {
        this.index = index;
        this.tag = tag;
        this.owner = owner;
        this.name = name;
        this.value = value;
        this.data = data;
    }
    /**
      * Returns the result {@link Type#getArgumentsAndReturnSizes} on {@link #value}.
      *
      * @return the result {@link Type#getArgumentsAndReturnSizes} on {@link #value} (memoized in
      *     {@link #info} for efficiency). This should only be used for {@link
      *     #CONSTANT_METHODREF_TAG}, {@link #CONSTANT_INTERFACE_METHODREF_TAG} and {@link
      *     #CONSTANT_INVOKE_DYNAMIC_TAG} symbols.
      */
    int getArgumentsAndReturnSizes() {
        if (info == 0) {
            info = Type.getArgumentsAndReturnSizes(value);
        }
        return info;
    }
}
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