code: public Properties getAllMessages(Locale locale) {
  
  		Properties props = new Properties();
  		Properties mergedProps = null;
  		if (locale == null) {
  			locale = Locale.getDefault();
  		}
  		mergedProps = getMergedProperties(locale).getProperties();
  
  		Set<Entry<Object, Object>> entries = mergedProps.entrySet();
  		for (Entry<Object, Object> entry : entries) {
  			String key = (String) entry.getKey();
  			if (LocaleUtils.matchesFilter(key, filters)) {
  
  				try {
  					// Use the property encoding of the file
  					String msg = getMessage(key, new Object[0], locale);
  					
  					// When war is deployed, the resource bundle are encoded in ISO 8859-1
  					// and otherwise in UTF-8 
  					// Check the following link for more detail https://grails.org/Internationalization
  					if(!warDeployed){
  						msg = new String(msg.getBytes(CHARSET_ISO_8859_1),
  								CHARSET_UTF_8);
  					}
  
  					props.put(key, msg);
  				} catch (NoSuchMessageException e) {
  					// This is expected, so it's OK to have an empty catch
  					// block.
  					if (LOGGER.isDebugEnabled())
  						LOGGER.debug("Message key [" + key + "] not found.");
  				} catch (UnsupportedEncodingException e) {
  					LOGGER.warn("Unable to convert value of message bundle associated to key '"
  							+ key + "' because the charset is unknown");
  				}
  			}
  		}
  		return props;
  	}
docs: Returns all the messages
  
  @return all the messages