Encapsulation helps in isolating implementation details from the behavior exposed to clients of a class (other classes/functions that are using this class), and gives you more control over coupling in your code. Consider this example, similar to the one in Robert Martin’s book Clean Code: public class Car { //… public float GetFuelPercentage() { /* … Read more
Is it because we do not want others to know the exact way we are storing data or managing data on the back-end? Yes, that’s the point. It is related to the concepts of abstraction and information hiding too. You provide a public setter that when invoked by the class client will have the effect … Read more
It doesn’t grant you anything extra beyond being concise. If you prefer the more verbose syntax, then by all means, use that. One advantage to using auto props is that it can potentially save you from making a silly coding mistake such as accidentally assigning the wrong private variable to a property. Trust me, I’ve … Read more
Encapsulation and information hiding are very closely linked concepts, though their precise definitions vary depending on who you talk to. The concept of “information hiding” was first described by Parnas (1972) who suggested that access to information should be restricted to reduce the interconnectedness of a system. He proposed that this would facilitate splitting of … Read more
Why is the default access modifier in JUnit 5 package-private? It’s not the “default”. There technically is no default. Rather, in JUnit Jupiter you have a choice: public, protected or package-private. What is the benefit of changing it to package-private? The benefit is that you don’t have type public anymore. If your IDE automatically generates … Read more
Typically, Python code strives to adhere to the Uniform Access Principle. Specifically, the accepted approach is: Expose your instance variables directly, allowing, for instance, foo.x = 0, not foo.set_x(0) If you need to wrap the accesses inside methods, for whatever reason, use @property, which preserves the access semantics. That is, foo.x = 0 now invokes … Read more
class A { public: int x; protected: int y; private: int z; }; class B : public A { // x is public // y is protected // z is not accessible from B }; class C : protected A { // x is protected // y is protected // z is not accessible from … Read more
Assume you have an age property. The user can enter a value of -10, which although is a valid number, is an invalid age. A setter method could have logic which would allow you to catch such things. Another scenario, would be to have the age field, but hide it. You could also have a … Read more
Many of the other answers hint at it, but I’m going to more explicitly say that yes, naive implementations of dependency injection can break encapsulation. The key to avoiding this is that calling code should not directly instantiate the dependencies (if it doesn’t care about them). This can be done in a number of ways. … Read more
By hiding the variable and adding methods now, the class designer allows for inserting arbitrary code into those methods in the future without breaking tons of code that use the attributes directly. Also note that providing a lot of accessor/mutator methods is generally a sign that your class design needs another look for possible improvement. … Read more