Regardless of how we get into this situation, as all code smells are, it will usually cost us in the long run. Other refactoring techniques to solve this are: Move, Extract, and Remove Methods. Here is a video showing how to refactor out this code smell. Usually these smells do not crop up right away, rather they accumulate over time as the program evolves (and especially when nobody makes an effort to eradicate them). The best smell is something easy to find but will lead to an interesting problem, like classes with data and no behavior. Owner: nobody Labels: rules (229) Priority: 5 Updated: 2012-10-07 Created: 2002-07-16 Creator: David Dixon-Peugh Private: No Same set of data is usually found together. Usually, it's because we either have an existing API that wants to accept or return an array, or we may find a clever way to loop through the elements in an array and use them which is quicker now than coding it as an object/class. . We ensure you always know what the latest are & how to use them. (Probably with the same name and such.) When we want our street address, we should ask for a property named something like address1, and not the item at index 1. Data Clumps: Data that looks similar maybe belongs to the same class. Fill in your details below or click an icon to log in: You are commenting using your WordPress.com account. That's what we have in our misbehaving array. Data clumps are groups of data items that are related and are always used or passed around together. Code smells indicate a deeper problem, but as the name suggests, they are sniffable or quick to spot. Data Clumps Sometimes different parts of the code contain identical groups of variables (such as parameters for connecting to a database). Post was not sent - check your email addresses! CODE SMELL/ BAD SMELL Types of Code Smell Duplicate Code Example 1 extern int a[]; extern int b[]; int sumofa = 0; for (int i = 0; i < 4; i + +) sum += a[i]; int averageofa= sum/4; —————- int sumofb = 0; for (int i = 0; i < 4; i + +) sum += b[i]; int averageofb = sumofb/4; Extract method int calc-average(int* array) int sum= 0; for (int i = 0; i < 4; i + +) sum + =array[i]; return sum/4; These clumps should be … Detecting Code Smells. | Twitter: @gothinkster. No duplication of data validation: You can encapsulate any additional logic for handling the types of data in that type, for example, constraints around what is a valid zip code. A code smell is “a surface indication that usually corresponds to a deeper problem in the system.” Being able to catch code smells early will make it easier to refactor into code that is more extendable, readable, and supportable. That code smell is very generic and includes many different variations. Even when those items are all the same data type, they can ultimately be different kinds of data. Imagine that you copy the database credentials in many services to create a new connection object. Let's look at a couple of example arrays used properly. Proper use of data types (and here I don't just mean strings and numbers) is one of the foundations of any application. Code Smells. Often you'll see the same three or four data items together in many places: instance variables in a couple of classes, and parameters in many method signatures. This one: This is no better. ... whole object. With a good refactoring tool, like ReSharper, this code smell can be refactored out of the codebase safely. Visit Us: thinkster.io | Facebook: @gothinkster These clumps should be turned into their own classes. Let's look at a couple of example arrays used properly. Create types for contact information and credit card information, then pass those to the Submit method instead: public bool SubmitCreditCardOrder(ContactInformation customerInfo, CreditCard card, decimal saleAmount) { // … submit order }. Usually these smells do not crop up right away, rather they accumulate over time as the program evolves (and especially when nobody makes an effort to eradicate them). Data items tend to be like children; they enjoy hanging around in groups together. Overview; Transcript; 1.9 Data Clumps. Of how we get into this situation, as all code smells are, it will usually cost us the. Is accessed: what 's wrong with this use of an array is accessed: what 's wrong this! ), you are passing everything that you need, and development methodology possibly indicates a problem... Be removed example arrays used properly we get into this situation, as all code require. 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