public static <T> T getObj(String className)
      throws ClassNotFoundException, InstantiationException, IllegalAccessException {
    return (T) Class.forName(className).newInstance();
  }
Instantiate a class instance from a given className.
@param className
@param <T>
@return
@throws ReflectiveOperationException
ambry-utils/src/main/java/com/github/ambry/utils/Utils.java