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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

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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) 2000-2013 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 class TypePath {

    /**

     * A type path step that steps into the element type of an array type. See

     * {@link #getStep getStep}.

     */

    /**

     * A type path step that steps into the nested type of a class type. See

     * {@link #getStep getStep}.

     */

    /**

     * A type path step that steps into the bound of a wildcard type. See

     * {@link #getStep getStep}.

     */

    /**

     * A type path step that steps into a type argument of a generic type. See

     * {@link #getStep getStep}.

     */

    /**

     * The byte array where the path is stored, in Java class file format.

     */

    byte[] b;

    /**

     * The offset of the first byte of the type path in 'b'.

     */

    int offset;

    /**

     * Creates a new type path.

     *

     * @param b

     *            the byte array containing the type path in Java class file

     *            format.

     * @param offset

     *            the offset of the first byte of the type path in 'b'.

     */

    TypePath(byte[] b, int offset) {

        this.b = b;

        this.offset = offset;

    }

    /**

     * Returns the length of this path.

     *

     * @return the length of this path.

     */

    public int getLength() {

        return b[offset];

    }

    /**

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

     *

     * @param index

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

     * @return {@link #ARRAY_ELEMENT ARRAY_ELEMENT}, {@link #INNER_TYPE

     *         INNER_TYPE}, {@link #WILDCARD_BOUND WILDCARD_BOUND}, or

     *         {@link #TYPE_ARGUMENT TYPE_ARGUMENT}.

     */

    public int getStep(int index) {

        return b[offset + 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 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(int index) {

        return b[offset + 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 null or empty.

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

     */

    public static TypePath fromString(final String typePath) {

        if (typePath == null || typePath.length() == 0) {

            return null;

        }

        int n = typePath.length();

        ByteVector out = new ByteVector(n);

        out.putByte(0);

        for (int i = 0; i < n;) {

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

            if (c == '[') {

                out.put11(ARRAY_ELEMENT, 0);

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

                out.put11(INNER_TYPE, 0);

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

                out.put11(WILDCARD_BOUND, 0);

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

                int typeArg = c - '0';

                while (i < n && (c = typePath.charAt(i)) >= '0' && c <= '9') {

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

                    i += 1;

                }

                if (i < n && typePath.charAt(i) == ';') {

                    i += 1;

                }

                out.put11(TYPE_ARGUMENT, typeArg);

            }

        }

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

        return new TypePath(out.data, 0);

    }

    /**

     * Returns a string representation of this type path. {@link #ARRAY_ELEMENT

     * ARRAY_ELEMENT} steps are represented with '[', {@link #INNER_TYPE

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

     * with '*' and {@link #TYPE_ARGUMENT 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:

                result.append('_');

            }

        }

        return result.toString();

    }

}