# File lib/active_record/associations.rb, line 286
      def has_many(association_id, options = {})
        validate_options([ :foreign_key, :class_name, :exclusively_dependent, :dependent, :conditions, :order, :finder_sql, :counter_sql, 
                                                                                                         :before_add, :after_add, :before_remove, :after_remove ], options.keys)
        association_name, association_class_name, association_class_primary_key_name =
              associate_identification(association_id, options[:class_name], options[:foreign_key])
 
        require_association_class(association_class_name)

        if options[:dependent] and options[:exclusively_dependent]
          raise ArgumentError, ':dependent and :exclusively_dependent are mutually exclusive options.  You may specify one or the other.' # ' ruby-mode
        # See HasManyAssociation#delete_records.  Dependent associations
        # delete children, otherwise foreign key is set to NULL.
        elsif options[:dependent]
          module_eval "before_destroy '#{association_name}.each { |o| o.destroy }'"
        elsif options[:exclusively_dependent]
          module_eval "before_destroy { |record| #{association_class_name}.delete_all(%(#{association_class_primary_key_name} = \#{record.quoted_id})) }"
        end

        add_multiple_associated_save_callbacks(association_name)
                                add_association_callbacks(association_name, options)
                                
        collection_accessor_methods(association_name, association_class_name, association_class_primary_key_name, options, HasManyAssociation)
        
        # deprecated api
        deprecated_collection_count_method(association_name)
        deprecated_add_association_relation(association_name)
        deprecated_remove_association_relation(association_name)
        deprecated_has_collection_method(association_name)
        deprecated_find_in_collection_method(association_name)
        deprecated_find_all_in_collection_method(association_name)
        deprecated_collection_create_method(association_name)
        deprecated_collection_build_method(association_name)
      end