code: public void setOption(String key) throws UnsupportedOption {
  		if (key.equals(IGNORE_SCHEMA_ID)) {
  			options.add(key);
  		} else {
  			throw new UnsupportedOption("DecodingOption '" + key
  					+ "' is unknown!");
  		}
  	}
docs: Enables given option.
  
  <p>
  Note: Some options (e.g. INCLUDE_SCHEMA_ID) will only take effect if the
  EXI options document is set to encode options in general (see
  INCLUDE_OPTIONS).
  </p>
  
  @param key
  referring to a specific option
  
  @throws UnsupportedOption
  if option is not supported