private static String saveConvert(String theString,
                                      boolean escapeSpace,
                                      boolean escapeUnicode) {
        int len = theString.length();
        int bufLen = len * 2;
        if (bufLen < 0) {
            bufLen = Integer.MAX_VALUE;
        }
        StringBuffer outBuffer = new StringBuffer(bufLen);

        for (int x = 0; x < len; x++) {
            char aChar = theString.charAt(x);
            // Handle common case first, selecting largest block that
            // avoids the specials below
            if ((aChar > 61) && (aChar < 127)) {
                if (aChar == '\\') {
                    outBuffer.append('\\');
                    outBuffer.append('\\');
                    continue;
                }
                outBuffer.append(aChar);
                continue;
            }
            switch (aChar) {
                case ' ':
                    if (x == 0 || escapeSpace) {
                        outBuffer.append('\\');
                    }
                    outBuffer.append(' ');
                    break;
                case '\t':
                    outBuffer.append('\\');
                    outBuffer.append('t');
                    break;
                case '\n':
                    outBuffer.append('\\');
                    outBuffer.append('n');
                    break;
                case '\r':
                    outBuffer.append('\\');
                    outBuffer.append('r');
                    break;
                case '\f':
                    outBuffer.append('\\');
                    outBuffer.append('f');
                    break;
                case '=': // Fall through
                case ':': // Fall through
                case '#': // Fall through
                case '!':
                    outBuffer.append('\\');
                    outBuffer.append(aChar);
                    break;
                default:
                    if (((aChar < 0x0020) || (aChar > 0x007e)) & escapeUnicode) {
                        outBuffer.append('\\');
                        outBuffer.append('u');
                        outBuffer.append(toHex((aChar >> 12) & 0xF));
                        outBuffer.append(toHex((aChar >> 8) & 0xF));
                        outBuffer.append(toHex((aChar >> 4) & 0xF));
                        outBuffer.append(toHex(aChar & 0xF));
                    } else {
                        outBuffer.append(aChar);
                    }
            }
        }
        return outBuffer.toString();
    }
Converts unicodes to encoded &#92;uxxxx and escapes
special characters with a preceding slash
stroom-importexport/stroom-importexport-impl/src/main/java/stroom/importexport/impl/PropertiesSerialiser.java