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Java can you override a protected method

2022.01.06 17:58




















Let's see an example to determine whether the protected method is overridden to sub-class using default access modifier. Let's see an example to determine whether the protected method is overridden to sub-class using public access modifier. JavaTpoint offers too many high quality services. Mail us on [email protected] , to get more information about given services.


Please mail your requirement at [email protected] Duration: 1 week to 2 week. Java Training Java Tutorial. Abstract class Interface Abstract vs Interface. Package Access Modifiers Encapsulation. Exception in thread "main" java. Error: Unresolved compilation problem: The field A.


Try to access the protected variable outside the class within the package. Error: Unresolved compilation problem: The method msg from the type A is not visible. Try to access the protected method outside the package using inheritance. Error: Unresolved compilation problem:. Error: Unresolved compilation problem: The constructor A String is not visibles. Error: Unresolved compilation problem: Cannot reduce the visibility of the inherited method from A. Next Topic Java Keywords. Reinforcement Learning.


R Programming. React Native. Python Design Patterns. Python Pillow. If you want to read about the best guidelines for allowing future extensibility, you can read materials around applications of Open-Closed Principle OCP - beware though, it is one of the hardest SOLID principles to apply, unless you can see the future or have enough experience to make very reliable guesses. Also, I'd recommend reading about Composition vs. Inheritance, since sometimes its better not to extend classes at all, but to compose them of other exchangeable objects instead.


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Learn more. Why public access level method get overridden in java? Ask Question. Asked 6 years, 11 months ago. Active 6 years, 7 months ago. Viewed 1k times. Improve this question. I don't think you understand encapsulation as it applies to inheritance as well as you think you do. May I suggest you do some reading about the Liskov substitution principle? Jules i think, LSP is well said in the below answer.


Do you still suggest me to read LSP? Add a comment. Active Oldest Votes. Improve this answer. Infact i said the same in my above comments about final , it is my mistake that i read this answer now because of less votes : Sorry about that!!! I suppose you could declare something protected final, but it would be odd.


You'd be saying you already know all the ways someone might want to extend your class, and nobody will ever have a good reason to override that method. Basically, you'd be encouraging subclasses why else have protected methods? As for the terminology, I've always seen public , protected , and private described as either "accessibility" or "visibility" modifiers. If a subclass defines a static method with the same signature as a static method in the superclass, then the method in the subclass hides the one in the superclass.


The distinction between hiding a static method and overriding an instance method has important implications:. Consider an example that contains two classes. The first is Animal , which contains one instance method and one static method:. The Cat class overrides the instance method in Animal and hides the static method in Animal.


The main method in this class creates an instance of Cat and invokes testClassMethod on the class and testInstanceMethod on the instance. As promised, the version of the hidden static method that gets invoked is the one in the superclass, and the version of the overridden instance method that gets invoked is the one in the subclass. Default methods and abstract methods in interfaces are inherited like instance methods. However, when the supertypes of a class or interface provide multiple default methods with the same signature, the Java compiler follows inheritance rules to resolve the name conflict.


These rules are driven by the following two principles:. Methods that are already overridden by other candidates are ignored. This circumstance can arise when supertypes share a common ancestor. The method Dragon. If two or more independently defined default methods conflict, or a default method conflicts with an abstract method, then the Java compiler produces a compiler error.


You must explicitly override the supertype methods.