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Why is private not protected?
If that field is private in the base class then the subclass cannot access it, cannot extend the functionality. If the field is protected it can do so. Subclasses have a special relationship to the base class that other classes elsewhere in the class hierarchy don’t have: they inherit the base class members.
Why and when do we use protected instead of private?
– Private data members cannot be accessed outside the class. – When a class inherits a base class, all the data members except the private get inherited into it. So if we want data members to be accessible to only derived classes and not privately or publicly accessible, then we can use protected.
How is protected visibility different from private or public visibility?
The difference is as follows: Public :: A public variable or method can be accessed directly by any user of the class. Protected :: A protected variable or method cannot be accessed by users of the class but can be accessed inside a subclass that inherits from the class.
Is it possible to have a protected class?
No, we cannot declare a top-level class as private or protected. It can be either public or default (no modifier). If it does not have a modifier, it is supposed to have a default access.
Why would you make a variable private?
Making a variable private “protects” its value when the code runs. At this level, we are not concerned with protecting it from other programmers changing the code itself. The point of so-called “data hiding” is to keep internal data hidden from other classes which use the class.
What’s the difference between protected and private fields?
Protected parts are potentially affected by every existing subclass, and every subclass yet to be written, which is also an infinite amount of code. The conclusion is that protected gives you very little more than public, whereas private gives you a real improvement.
When to change a protected field in Java?
But be aware that, as soon as you accept to have subclasses of your class, and there is a protected field or method, this field or method is part of the public API of the class, and may not be changed later without breaking subclasses. A class that is not intended to be inherited should be made final (in Java).
Why is an outer Java class cannot be private or protected?
Because ‘a’ field is protected, we can access it in any way we want to inside the package but outside of the package ‘com.example’ it is only accessible through inheritance and because class ‘B’ is extending class ‘A’ we can use field ‘a’ inside class ‘B’ only as we are doing in printUsingInheritance () method.
How are private fields declared in JavaScript class?
Private instance fields are declared with # names (pronounced “hash names”), which are identifiers prefixed with #. The # is a part of the name itself. Private fields are accessible on the class constructor from inside the class declaration itself. They are used for declaration of field names as well as for accessing a field’s value.