# ri > ActiveRecord::ReadonlyAttributes::ClassMethods

## [ActiveRecord::ReadonlyAttributes::ClassMethods](https://www.chedong.com/phpMan.php/perldoc/ActiveRecord%3A%3AReadonlyAttributes%3A%3AClassMethods/markdown)

(from /home/chedong/.local/share/rdoc)
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## Instance methods:

  attr_readonly
  readonly_attributes