I am creating video tutorials of this website tutorials/articles/guides and publishing on my youtube channel at Java Guides - YouTube Channel. The Interface Segregation Principle (ISP) ISP states that no client should be forced to depend on methods it does not use. Interface segregation principle "Many client-specific interfaces are better than one general-purpose interface." says is that your interface should not be bloated with methods that implementing classes don’t require. The Wiki says: “The interface-segregation principle (ISP) states that no client should be forced to depend on methods it does not use.” ISP splits interfaces which are very large into smaller and more specific ones so that clients will only have to know about the methods that are of interest to them. About Me | Subscribe to my youtube channel for daily useful videos updates. Each “role interface” declares one or more methods for a specific behavior. Interface segregation principle states that if any particular interface member is not intended to be implemented by any of the classes that implement the interface, it must not be in the interface. Each segregated interface is a lean interface as it only contains methods which are required for a specific client. The idea for this principle is to use customer centric interface. In this case it is the … Happy coding. When clients are forced to depend upon interfaces that they don’t use, then those clients are subject to changes to those interfaces. An addition of a method or change to a method signature requires modifying all the implementation classes even if some of them don’t use the method. ISP: The dependency of one class to another one should depend on the smallest possible interface. Coming up next is Understanding SOLID Principles: Interface segregation principle If this post was helpful please share it and stay tuned on my other articles. A few years later, she [Interface Segregation Principle (ISP)] splits interfaces that are very large into smaller and more specific ones so that clients will only have to know about the methods that are of interest to them…ISP is intended to keep a system decoupled and thus easier to refactor, change, and redeploy. It is aimed at beginners and intermediate developers. If a class implements an interface and some of its methods throw a NotImplementedException , that’s bad, but has nothing to do with the ISP. Interface Segregation Principle Article History Interface Segregation Principle. This is the main idea of the Interface Segregation Principle. The Interface Segregation Principle. YouTube | As we discussed in our review of the Open/Closed Principle, interfaces are a means of programming with abstractions rather than concretions. In this case. Let us understand the Interface Segregation Principle in C# with an example.. The Interface Segregation Principle is one of the SOLID Principles, coined by Robert C. Martin. The Interface Segregation Principle was defined by Robert C. Martin and states: Clients should not be forced to depend on methods they do not use. Interface Segregation Principle avoids the design drawbacks associated with a fat interface by refactoring each fat interface into multiple segregated interfaces. Within the world of C#, this means that an interface with many methods on it, tends to break this principle. To remind (from wiki):. 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