Code refactoring

• Techniques that allow for more abstraction
  • Encapsulate Field – force code to access the field with getter and setter methods
  • Generalize Type – create more general types to allow for more code sharing
  • Replace type-checking code with State/Strategy^[6]
  • Replace conditional with polymorphism ^[7]
• Techniques for breaking code apart into more logical pieces
  • Componentization breaks code down into reusable semantic units which present clear, well-defined, simple-to-use interfaces.
  • Extract Class moves part of the code from an existing class into a new class.
  • Extract Method, to turn part of a larger method into a new method. By breaking down code in smaller pieces, it is more easily understandable. This is also applicable to functions.
• Techniques for improving names and location of code
• Move Method or Move Field – move to a more appropriate Class or source file
• Rename Method or Rename Field – changing the name into a new one that better reveals its purpose
• Pull Up – in OOP, move to a superclass
• Push Down – in OOP, move to a subclass

from here