code: public static void incrementVersion(Object target) {
          MetaClass metaClass = GroovySystem.getMetaClassRegistry().getMetaClass(target.getClass());
          if (metaClass.hasProperty(target, GormProperties.VERSION)!=null) {
              Object version = metaClass.getProperty(target, GormProperties.VERSION);
              if (version instanceof Long) {
                  Long newVersion = (Long) version + 1;
                  metaClass.setProperty(target, GormProperties.VERSION, newVersion);
              }
          }
      }
docs: Increments the entities version number in order to force an update
  @param target The target entity