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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

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 * 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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 * You should have received a copy of the GNU General Public License version

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/*

 * 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;

/**

 * The path to a type argument, wildcard bound, array element type, or static inner type within an

 * enclosing type.

 *

 * @author Eric Bruneton

 */

public final class TypePath {

    /** A type path step that steps into the element type of an array type. See {@link #getStep}. */

    public static final int ARRAY_ELEMENT = 0;

    /** A type path step that steps into the nested type of a class type. See {@link #getStep}. */

    public static final int INNER_TYPE = 1;

    /** A type path step that steps into the bound of a wildcard type. See {@link #getStep}. */

    public static final int WILDCARD_BOUND = 2;

    /** A type path step that steps into a type argument of a generic type. See {@link #getStep}. */

    public static final int TYPE_ARGUMENT = 3;

    /**

      * The byte array where the 'type_path' structure - as defined in the Java Virtual Machine

      * Specification (JVMS) - corresponding to this TypePath is stored. The first byte of the

      * structure in this array is given by {@link #typePathOffset}.

      *

      * @see <a

      *     href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.20.2">JVMS

      *     4.7.20.2</a>

      */

    private final byte[] typePathContainer;

    /** The offset of the first byte of the type_path JVMS structure in {@link #typePathContainer}. */

    private final int typePathOffset;

    /**

      * Constructs a new TypePath.

      *

      * @param typePathContainer a byte array containing a type_path JVMS structure.

      * @param typePathOffset the offset of the first byte of the type_path structure in

      *     typePathContainer.

      */

    TypePath(final byte[] typePathContainer, final int typePathOffset) {

        this.typePathContainer = typePathContainer;

        this.typePathOffset = typePathOffset;

    }

    /**

      * Returns the length of this path, i.e. its number of steps.

      *

      * @return the length of this path.

      */

    public int getLength() {

        // path_length is stored in the first byte of a type_path.

        return typePathContainer[typePathOffset];

    }

    /**

      * Returns the value of the given step of this path.

      *

      * @param index an index between 0 and {@link #getLength()}, exclusive.

      * @return one of {@link #ARRAY_ELEMENT}, {@link #INNER_TYPE}, {@link #WILDCARD_BOUND}, or {@link

      *     #TYPE_ARGUMENT}.

      */

    public int getStep(final int index) {

        // Returns the type_path_kind of the path element of the given index.

        return typePathContainer[typePathOffset + 2 * index + 1];

    }

    /**

      * Returns the index of the type argument that the given step is stepping into. This method should

      * only be used for steps whose value is {@link #TYPE_ARGUMENT}.

      *

      * @param index an index between 0 and {@link #getLength()}, exclusive.

      * @return the index of the type argument that the given step is stepping into.

      */

    public int getStepArgument(final int index) {

        // Returns the type_argument_index of the path element of the given index.

        return typePathContainer[typePathOffset + 2 * index + 2];

    }

    /**

      * Converts a type path in string form, in the format used by {@link #toString()}, into a TypePath

      * object.

      *

      * @param typePath a type path in string form, in the format used by {@link #toString()}. May be

      *     {@literal null} or empty.

      * @return the corresponding TypePath object, or {@literal null} if the path is empty.

      */

    public static TypePath fromString(final String typePath) {

            return null;

        }

        int typePathLength = typePath.length();

        ByteVector output = new ByteVector(typePathLength);

        output.putByte(0);

        int typePathIndex = 0;

        while (typePathIndex < typePathLength) {

            char c = typePath.charAt(typePathIndex++);

            if (c == '[') {

                output.put11(ARRAY_ELEMENT, 0);

            } else if (c == '.') {

                output.put11(INNER_TYPE, 0);

            } else if (c == '*') {

                output.put11(WILDCARD_BOUND, 0);

            } else if (c >= '0' && c <= '9') {

                int typeArg = c - '0';

                while (typePathIndex < typePathLength) {

                    c = typePath.charAt(typePathIndex++);

                    if (c >= '0' && c <= '9') {

                        typeArg = typeArg * 10 + c - '0';

                    } else if (c == ';') {

                        break;

                    } else {

                        throw new IllegalArgumentException();

                    }

                }

                output.put11(TYPE_ARGUMENT, typeArg);

            } else {

                throw new IllegalArgumentException();

            }

        }

        output.data[0] = (byte) (output.length / 2);

        return new TypePath(output.data, 0);

    }

    /**

      * Returns a string representation of this type path. {@link #ARRAY_ELEMENT} steps are represented

      * with '[', {@link #INNER_TYPE} steps with '.', {@link #WILDCARD_BOUND} steps with '*' and {@link

      * #TYPE_ARGUMENT} steps with their type argument index in decimal form followed by ';'.

      */

    @Override

    public String toString() {

        int length = getLength();

        StringBuilder result = new StringBuilder(length * 2);

        for (int i = 0; i < length; ++i) {

            switch (getStep(i)) {

                case ARRAY_ELEMENT:

                    result.append('[');

                    break;

                case INNER_TYPE:

                    result.append('.');

                    break;

                case WILDCARD_BOUND:

                    result.append('*');

                    break;

                case TYPE_ARGUMENT:

                    result.append(getStepArgument(i)).append(';');

                    break;

                default:

                    throw new AssertionError();

            }

        }

        return result.toString();

    }

    /**

      * Puts the type_path JVMS structure corresponding to the given TypePath into the given

      * ByteVector.

      *

      * @param typePath a TypePath instance, or {@literal null} for empty paths.

      * @param output where the type path must be put.

      */

    static void put(final TypePath typePath, final ByteVector output) {

        if (typePath == null) {

            output.putByte(0);

        } else {

            int length = typePath.typePathContainer[typePath.typePathOffset] * 2 + 1;

            output.putByteArray(typePath.typePathContainer, typePath.typePathOffset, length);

        }

    }

}