This will avoid code duplication. refactoring course, it explains all 89 code smells and refactorings. It takes practice and experience to recognise code smells: symptoms of bad design which indicate deeper proble Generally, any method longer than ten lines should make you start asking questions. All these smells are incomplete or incorrect application of object-oriented programming principles. This course covers when and how to refactor code, as well as a wide variety of "code smells" that may indicate some refactoring is warranted. Relatively rare use of switch and case operators is one of the hallmarks of object-oriented code. Code Smells • Indicators that something may be wrong in the code • Can occur both in production code and test code In the following slides, the code smells and refactorings are taken from Fowler’s Refactoring, “Refactoring Test Code” by Arie van Deursen, Leon Moonen, Alex van den Bergh, and Gerard Kok, published in When you feel the need to write a comment, first try to refactor the code so that any comment becomes superfluous. Generally speaking your code will be a lot easier to read … Moved to the contents of the separate card about Technical Debt to this card to make the subject more comprehensive. Bringing a new pair of eyes to the code is often a prime situation to detect code that smells and propose new patterns. In this article I’ll be walking through an example of how to refactor the Long Method code smell. Fowler’s book is an excellent resource that helps us identify some common code smells and eliminate them. All the smells in this group contribute to excessive coupling between classes or show what happens if coupling is replaced by excessive delegation. STUDY. The course concludes with a refactoring kata that students can perform on their own to practice their refactoring skills. Things to notice here PrintOwing function, has some comments to understand what is the purpose of following portion of code. / Refactoring / Code Smells / Couplers. Code Smells Bloaters. Code smells become more apparent with passing time. Instead, they indicate weaknesses in design that may slow down development or increase the risk of bugs or failures in the future. Coding Standards(FxCop, Code Metrics) 4. They are called smells since they are volatile. All the smells in this group contribute to excessive coupling between classes or show what happens if coupling is replaced by excessive delegation. Refactoring is widely recognized as an efficient technique to fix code smells and reduce the increasing complexity of software systems. JSparrow [7], which have capabilities of detecting classic code smells and applying automatic refactoring on those. Its essence is applying a series of small behavior-preserving transformations, each of which "too small to be worth doing". Out of the seven smells, JDeodrant detected and refactored god class, feature envy, and type checking whereas JSparrow could detect and refactor four smells namely cyclic dependency, shotgun surgery, god method, and spaghetti code. -Martin Fowler Before we look into some tips for refactoring code, lets learn about the some symptoms of code smell. We have not adopted all the practices, but use the majority of the practices. Code smells are easy to spot and fix, but they may be just symptoms of a deeper problem with code. 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