CS 110: Introduction to Programming in Java

Step 2: Identifying Methods

• Identify within the methods in the classes any repetition that can be either avoided or done with a helper method.
  • Circle one instance of the repeated code segment. Next to it, indicate a good Intention Revealing Name for the helper method. Also, write down any values that are different each time and so should be passed as parameters.
  • Cross out the other occurences of the repeated code. Write a call to the new helper method in the margin.

Step 3: Creating an approriate inheritance structure

• Consider the following three inheritance structures:
• Which structure corresponds to the current code?
• How do the other structures differ from the current structure in terms of what they represent?
• What would be an appropriate (Intention Revealing Name) name for the ? in the 3^rd structure?
• Which structure would be most appropriate to represent pieces in a chess game?
• Where would you add other chess pieces, such as a Knight, Bishop, King and Queen to your drawing?

Step 4: Finishing Up

• Given the structure you chose in Step 3, identify which instance variables currently in Pawn should be in each of your classes.
• Also, identify which methods should be in each of your classes.
  • Are there any methods that can be generalized and so used in classes where they are not currently used? Are there additional helper methods you could identify?
  • Are there methods that can be inherited from one class to another?
  • Are there methods that should be redefined in a subclass?
  • Are there any methods that belong only in a subclass and not in its superclass?