Encoding Unicodes

Strings.java

public static String convertToJavaString(String theString, boolean useUnicode) {
  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 ' ':
        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 '\b':
        outBuffer.append('\\');
        outBuffer.append('b');
        break;
      case '\'':
        outBuffer.append('\\');
        outBuffer.append('\'');
        break;
      case '"':
        outBuffer.append('\\');
        outBuffer.append('"');
        break;
      default:
        if (useUnicode && ((aChar < 0x0020) || (aChar > 0x007e))) {
          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();
}