code: private String getPatternString( String key )
          throws MissingResourceException
      {
          ResourceBundle bundle = getBundle();
          Object object = bundle.getObject( key );
  
          // is the resource a single string
          if( object instanceof String )
          {
              return (String) object;
          }
          else if( object instanceof String[] )
          {
              //if string array then randomly pick one
              String[] strings = (String[]) object;
              return strings[ RANDOM.nextInt( strings.length ) ];
          }
          else
          {
              throw new MissingResourceException( "Unable to find resource of appropriate type.",
                                                  "java.lang.String",
                                                  key
              );
          }
      }
docs: Utility method to retrieve a string from ResourceBundle.
  If the key is a single string then that will be returned.
  If key refers to string array then a random string will be chosen.
  Other types cause an exception.
  
  @param key the key to resource
  
  @return the string resource
  
  @throws MissingResourceException if an error occurs