Strategy Pattern for Multiple Type Codes

From: Clint Shank (clintshank_at_hotmail.com)
Date: 02/10/05

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    Date: 10 Feb 2005 12:21:41 -0800

    Please bear with the contrived example... Suppose we have an Employee
    class whose functionality depends on several type codes,
    manager/engineer and hourly/salary. Now, any Employee can be any
    combination (manager/hourly, manager/salary, engineer/hourly,
    engineer/salary). Some of the behavior depends on just the
    manager/engineer type code. Some of the behavior depends on the
    hourly/salary type code. And some of the behavior depends on all four
    cases. Specifically,

    Case 1: Just engineer/manager
       if (engineer)
          do engineer behavior
       else
          do manager behavior

    Case 2: All 4
       if (engineer)
          if (hourly)
             do engineer/hourly behavior
          else
             do engineer/salary behavior
       else
          if (hourly)
             do manager/hourly behavior
          else
             do manager/salary behavior

    Case 3: 3 cases
       if (engineer)
          do engineer behavior that doesn't care about hourly/salary
       else
          if (hourly)
             do manager/hourly behavior
          else
             do manager/salary behavior

    So these are the contrived cases that actually map to my real world
    cases. There's not many, maybe only these three, but I'm wondering if
    I should do something clever with the Strategy design pattern. Only
    there are multiple type codes and the behavior sometimes depends on
    both. I'm not sure how to cleanly separate that. Does anybody have
    any suggestions? Leave as is? Only a Manager/Engineer Strategy since
    all the cases depend on that distinction? Two Strategy hierarchies?

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