code: public static void put(Writer writer, char value) throws IOException {
  		writer.write("\"");
  		writer.write(sanitize(value));
  		writer.write("\"");
  	}
docs: Writes the given value with the given writer, sanitizing with {@link #sanitize(String)} as a valid JSON-formatted data.
  @param writer
  @param value
  @throws IOException
  @author vvakame