code: protected static Charset getCharset(final Map<String, String> properties) {
  		String charsetName = properties.get("charset");
  		try {
  			return charsetName == null ? Charset.defaultCharset() : Charset.forName(charsetName);
  		} catch (IllegalArgumentException ex) {
  			InternalLogger.log(Level.ERROR, "Invalid charset: " + charsetName);
  			return Charset.defaultCharset();
  		}
  	}
docs: Extracts the charset from configuration. The default charset will be returned, if no charset is defined or the
  defined charset doesn't exist.
  
  @param properties
  Configuration for writer
  @return Configured charset