public static Object unescapeValue()

in ldap/model/src/main/java/org/apache/directory/api/ldap/model/name/Rdn.java [1299:1454]
131 lines of code
38 McCabe index (conditional complexity)

    public static Object unescapeValue( String value )
    {
        if ( Strings.isEmpty( value ) )
        {
            return "";
        }

        char[] chars = value.toCharArray();

        // If the value is contained into double quotes, return it as is.
        if ( ( chars[0] == '\"' ) && ( chars[chars.length - 1] == '\"' ) )
        {
            return new String( chars, 1, chars.length - 2 );
        }

        if ( chars[0] == '#' )
        {
            if ( chars.length == 1 )
            {
                // The value is only containing a #
                return Strings.EMPTY_BYTES;
            }

            if ( ( chars.length % 2 ) != 1 )
            {
                throw new IllegalArgumentException( I18n.err( I18n.ERR_13613_VALUE_NOT_IN_HEX_FORM_ODD_NUMBER ) );
            }

            // HexString form
            byte[] hexValue = new byte[( chars.length - 1 ) / 2];
            int pos = 0;

            for ( int i = 1; i < chars.length; i += 2 )
            {
                if ( Chars.isHex( chars, i ) && Chars.isHex( chars, i + 1 ) )
                {
                    hexValue[pos++] = Hex.getHexValue( chars[i], chars[i + 1] );
                }
                else
                {
                    throw new IllegalArgumentException( I18n.err( I18n.ERR_13614_VALUE_NOT_IN_HEX_FORM ) );
                }
            }

            return hexValue;
        }
        else
        {
            boolean escaped = false;
            boolean isHex = false;
            byte pair = -1;
            int pos = 0;

            byte[] bytes = new byte[chars.length * 6];

            for ( int i = 0; i < chars.length; i++ )
            {
                if ( escaped )
                {
                    escaped = false;

                    switch ( chars[i] )
                    {
                        case '\\':
                        case '"':
                        case '+':
                        case ',':
                        case ';':
                        case '<':
                        case '>':
                        case '#':
                        case '=':
                        case ' ':
                            bytes[pos++] = ( byte ) chars[i];
                            break;

                        default:
                            if ( Chars.isHex( chars, i ) )
                            {
                                isHex = true;
                                pair = ( byte ) ( Hex.getHexValue( chars[i] ) << 4 );
                            }

                            break;
                    }
                }
                else
                {
                    if ( isHex )
                    {
                        if ( Chars.isHex( chars, i ) )
                        {
                            pair += Hex.getHexValue( chars[i] );
                            bytes[pos++] = pair;
                            isHex = false;
                            pair = 0;
                        }
                    }
                    else
                    {
                        switch ( chars[i] )
                        {
                            case '\\':
                                escaped = true;
                                break;

                            // We must not have a special char
                            // Specials are : '"', '+', ',', ';', '<', '>', ' ',
                            // '#' and '='
                            case '"':
                            case '+':
                            case ',':
                            case ';':
                            case '<':
                            case '>':
                            case '#':
                                if ( i != 0 )
                                {
                                    // '#' are allowed if not in first position
                                    bytes[pos++] = '#';
                                }
                                
                                break;

                            case ' ':
                                if ( ( i == 0 ) || ( i == chars.length - 1 ) )
                                {
                                    throw new IllegalArgumentException( I18n.err( I18n.ERR_13615_UNESCAPED_CHARS_NOT_ALLOWED ) );
                                }
                                else
                                {
                                    bytes[pos++] = ' ';
                                    break;
                                }

                            default:
                                if ( chars[i] < 128 )
                                {
                                    bytes[pos++] = ( byte ) chars[i];
                                }
                                else
                                {
                                    byte[] result = Unicode.charToBytes( chars[i] );
                                    System.arraycopy( result, 0, bytes, pos, result.length );
                                    pos += result.length;
                                }

                                break;
                        }
                    }
                }
            }

            return Strings.utf8ToString( bytes, pos );
        }
    }