instance method association_accessor_methods

# File activerecord/lib/active_record/associations.rb, line 1435
        def association_accessor_methods(reflection, association_proxy_class)
          redefine_method(reflection.name) do |*params|
            force_reload = params.first unless params.empty?
            association = association_instance_get(reflection.name)

            if association.nil? || force_reload
              association = association_proxy_class.new(self, reflection)
              retval = force_reload ? reflection.klass.uncached { association.reload } : association._load
              if retval.nil? and association_proxy_class == BelongsToAssociation
                association_instance_set(reflection.name, nil)
                return nil
              end
              association_instance_set(reflection.name, association)
            end

            association.target.nil? ? nil : association
          end

          redefine_method("loaded_#{reflection.name}?") do
            association = association_instance_get(reflection.name)
            association && association.loaded?
          end

          redefine_method("#{reflection.name}=") do |new_value|
            association = association_instance_get(reflection.name)

            if association.nil? || association.target != new_value
              association = association_proxy_class.new(self, reflection)
            end

            association.replace(new_value)
            association_instance_set(reflection.name, new_value.nil? ? nil : association)
          end

          redefine_method("set_#{reflection.name}_target") do |target|
            return if target.nil? and association_proxy_class == BelongsToAssociation
            association = association_proxy_class.new(self, reflection)
            association.target = target
            association_instance_set(reflection.name, association)
          end
        end