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Java-Style getters and setters can increase production risks

This code insight counts one violation each time a class define getter or setter (one of then or both) for a given member. If the implementation of the class contain the following pattern: self.<member> then a violation will be counted if the class defines a getter/setter mehod compliant with the following naming (case insensitive) unless the declaration of this method is preceded with the decorator @property or @xxx.setter: (get|set)_*<member>

Why you should care

Python is not Java. If you need to set or get the members of a class or object, just expose the member publicly and access it directly. If you need to perform some computations before getting or setting the member, then use Python’s built-in property decorator. Usage of built-in property decorator allow to associate a member access syntax (<object>.<attribute>), to a treatment implemented by a function. this is usefull because:

• there is no "private attribute" concept in python's classes. But property decorator force getters and setter decorators force to call a getter for each access to a member.
• for existing client code accessing directly to members , it is possible to add data treatment throught getter and setter without needing to modify the client code.

  class P:
      def __init__(self,x):
          self.x = x

      @x.setter
      def x(self, x):
          if x < 0:
              self.__x = 0
          elif x > 1000:
              self.__x = 1000
          else:
              self.__x = x

      @property
      def x(self):
          return self.__x

Business Impacts

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CAST recommendations

References

http://docs.quantifiedcode.com/python-code-patterns/correctness/implementing_java-style_getters_and_setters.html [nz_btn text="See features" link="http://casthighlight.wpengine.com/outputs-analytics/" target="_self" icon="icon-stats" animate="false" animation_type="ghost" color="black" size="small" shape="rounded" type="normal" hover_normal="fill" hover_ghost="fill"][nz_btn text="How it works" link="http://casthighlight.wpengine.com/how-it-works/" target="_self" icon="icon-cog" animate="false" animation_type="ghost" color="black" size="small" shape="rounded" type="ghost" hover_normal="fill" hover_ghost="fill"]