code: public Object defineBean(String name, Object bean) {
          Object ret = getELContext().getBeans().get(name);
          getELContext().getBeans().put(name, bean);
          return ret;
      }
docs: Define a bean in the local bean repository
  @param name The name of the bean
  @param bean The bean instance to be defined.  If null, the definition
  of the bean is removed.