Merge "Switch ByteStringUtils over to HexEncoding impl"

package android.util;

import libcore.util.HexEncoding;

/**

 * A utility class for common byte array to hex string operations and vise versa.

 *

 * @hide

 */

public final class ByteStringUtils {

    private static final char[] HEX_LOWERCASE_ARRAY = "0123456789abcdef".toCharArray();

    private static final char[] HEX_UPPERCASE_ARRAY = "0123456789ABCDEF".toCharArray();

    private ByteStringUtils() {

    /* hide constructor */

            return null;

        }

        final int byteLength = bytes.length;

        final int charCount = 2 * byteLength;

        final char[] chars = new char[charCount];

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

            final int byteHex = bytes[i] & 0xFF;

            chars[i * 2] = HEX_UPPERCASE_ARRAY[byteHex >>> 4];

            chars[i * 2 + 1] = HEX_UPPERCASE_ARRAY[byteHex & 0x0F];

        }

        return new String(chars);

        return HexEncoding.encodeToString(bytes, true /* upperCase */);

    }

    /**

            return null;

        }

        final char[] chars = str.toCharArray();

        final int charLength = chars.length;

        final byte[] bytes = new byte[charLength / 2];

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

            bytes[i] =

                    (byte) (((getIndex(chars[i * 2]) << 4) & 0xF0)

                            | (getIndex(chars[i * 2 + 1]) & 0x0F));

        }

        return bytes;

    }

    private static int getIndex(char c) {

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

            if (HEX_UPPERCASE_ARRAY[i] == c || HEX_LOWERCASE_ARRAY[i] == c) {

                return i;

            }

        }

        return -1;

        return HexEncoding.decode(str, false /* allowSingleChar */);

    }

}