stringByAddingPercentEscapesUsingEncoding for Java

gistfile1.java

    public static String stringByAddingPercentEscapesUsingEncoding(String input, String encoding)
            throws UnsupportedEncodingException {
        byte[] inputBytes = input.getBytes(encoding);
        StringBuilder stringBuilder = new StringBuilder(inputBytes.length);
        for(int i = 0; i < inputBytes.length; ++i) {
            int charByte = inputBytes[i] < 0 ? inputBytes[i] + 256 : inputBytes[i];
            if( charByte <= 0x20 || charByte >= 0x7F ||
                    (charByte == 0x22 || charByte == 0x25 || charByte == 0x3C ||
                            charByte == 0x3E || charByte == 0x20 || charByte == 0x5B ||
                            charByte == 0x5C || charByte == 0x5D || charByte == 0x5E ||
                            charByte == 0x60 || charByte == 0x7b || charByte == 0x7c ||
                            charByte == 0x7d)) {
                stringBuilder.append(String.format("%%%02X", charByte));
            }
            else {
                stringBuilder.append((char)charByte);
            }
        }
        return stringBuilder.toString();
    }