Most of the time, it is dangerous to use protected because you break somewhat the encapsulation of your class, which could well be broken down by a poorly designed derived class.
What is the purpose of protected Java?
The protected modifier specifies that the member can only be accessed within its own package (as with package-private) and, in addition, by a subclass of its class in another package. The following table shows the access to members permitted by each modifier.
Is protected a code smell?
Protected attributes are great for encapsulating and controlling access to our properties. They might be warning us for another smell.
What is the purpose of protected variables?
Protected variables are those data members of a class that can be accessed within the class and the classes derived from that class. In Python, there is no existence of “Public” instance variables. However, we use underscore ‘_’ symbol to determine the access control of a data member in a class.
When should I use protected C++?
The protected keyword specifies access to class members in the member-list up to the next access specifier ( public or private ) or the end of the class definition. Class members declared as protected can be used only by the following: Member functions of the class that originally declared these members.
Can we override a protected method in Java?
Yes, the protected method of a superclass can be overridden by a subclass. If the superclass method is protected, the subclass overridden method can have protected or public (but not default or private) which means the subclass overridden method can not have a weaker access specifier.
How do I access protected Java?
The protected access modifier is accessible within the package. However, it can also accessible outside the package but through inheritance only. We can’t assign protected to outer class and interface. If you make any constructor protected, you cannot create the instance of that class from outside the package.
Should methods be public or private?
Generally you should expose as little as possible and make everything private that is possible. If you make a mistake and hide something you should be exposing, no problem, just make it public.
Is it good practice to make all methods public?
Yes it is very bad practice – you’re letting your tools make design decisions for you. I think the main problem here is that you’re trying to treat each individual method as a unit. This is generally the cause of all unit test woes.
Can we use protected for a class in Java?
No, we cannot declare a top-level class as private or protected. It can be either public or default (no modifier).
Can protected members be accessed by objects?
Protected members in a class are similar to private members as they cannot be accessed from outside the class. But they can be accessed by derived classes or child classes while private members cannot.
Why and when do we use protected instead of private access specifies?
A private access specifier is only accessible within the same class whereas a protected access specifier is accessible within the class , subclass and within the same package.
What is protected in OOP?
Protected means that a class and its subclasses have access to the variable, but not any other classes, they need to use a getter/setter to do anything with the variable. A private means that only that class has direct access to the variable, everything else needs a method/function to access or change that data.
Is @override mandatory in Java?
@Override @Override annotation informs the compiler that the element is meant to override an element declared in a superclass. Overriding methods will be discussed in Interfaces and Inheritance. While it is not required to use this annotation when overriding a method, it helps to prevent errors.
How do you call a protected method in Java?
If a class is not final, you can use an anonymous class to call its protected method: new ClassWithProtectedMethod() { @Override protected void method() { super. method(); } }. method();
What is protected vs private?
private: The type or member can be accessed only by code in the same class or struct . protected: The type or member can be accessed only by code in the same class , or in a class that is derived from that class .
What does protected class mean in Java?
In Java, protected means that the member can be accessed by any class in the same package and by subclasses even if they are in another packages.
How do I stop code smelling?
Eliminating code smells with refactoring
The best time to refactor code is before adding updates or new features to an application, as it is good practice to clean up existing code before programmers add any new code. Another good time to refactor code is after a team has deployed code into production.
Is it OK to call abstract method from constructor in Java?
It’s a very bad practice to call an abstract method from a constructor. Methods called from constructors should always be private or final, to prevent overriding.
Is it good practice to make all methods public in Java?
Everything they do should be covered by calling the public methods (if they have code in there that is not exercised by the public methods, then that should go). If the private code is too complex, the class is probably doing too many things and in want of refactoring. Making a method public is big commitment.
Why would you make a method private?
Private methods are useful for breaking tasks up into smaller parts, or for preventing duplication of code which is needed often by other methods in a class, but should not be called outside of that class.
How do you decide if a method should be public?
In general, If the Method fits in the overall “Persona” of the class, make it public. More technically, try not to break the abstraction. I would have given an example, but I do not know the context of your work and so examples might be irrelevant. If you do not need it, there is no need to make a Method public.
Should we mock private methods?
Mocking techniques should be applied to the external dependencies of the class and not to the class itself. If mocking of private methods is essential for testing our classes, it usually indicates a bad design.
What does super () __ Init__ do?
When you initialize a child class in Python, you can call the super(). __init__() method. This initializes the parent class object into the child class. In addition to this, you can add child-specific information to the child object as well.
Can we have protected constructor in Java?
Modifiers public, protected and, private are allowed with constructors. We can use a private constructor in a Java while creating a singleton class.
Can constructor be private?
Yes, we can declare a constructor as private. If we declare a constructor as private we are not able to create an object of a class. We can use this private constructor in the Singleton Design Pattern.
Are protected variables inherited Java?
Methods declared protected in a superclass must either be protected or public in subclasses; they cannot be private. Methods declared private are not inherited at all, so there is no rule for them.
What’s the difference between a protected method and a private method?
Protected methods are a balance between public and private methods. They are similar to private methods in that they cannot be accessed in the public scope. Neither the client nor the program can invoke them. However, objects of the same class can access each other’s protected methods.
What is the difference between private and protected and which one should we use as a rule of thumb?
A private member ( i ) is only accessible within the same class as it is declared. A member with no access modifier ( j ) is only accessible within classes in the same package. A protected member ( k ) is accessible within all classes in the same package and within subclasses in other packages.
Which has more visibility protected or default?
Contrary to how it might sound, protected is slightly less restrictive than the default level of accessibility. In addition to the default access afforded classes in the same package, protected members are visible to subclasses of the class, even if they are defined in a different package.
What is the most secure access modifier in Java?
Java private access modifier:
This is the most restrictive access modifier in Java. It can be applied for members only.
Is protected encapsulation?
Variables that can only be accessed through getter and setter calls are encapsulated. Protected – A variable or method that is protected can be accessed by code within the same class, by any classes that are in the same package and by all sub-classes in the same or other packages.
Why we use protected access specifier?
The protected keyword specifies access to class members in the member-list up to the next access specifier ( public or private ) or the end of the class definition. Class members declared as protected can be used only by the following: Member functions of the class that originally declared these members.
Can protected method be called?
protected access modifier allows your subclasses be outside your superclass package and yet still inherit pieces of the class including methods and constructors.. The only way the subclass can access the protected methods is by inheritance…
What happens if you don’t put @override?
Without it, you can change a method signature and forget to alter its overrides, with @Override, the compiler will catch it for you.
Is @override optional?
@Override is optional in Java. All it does is validate that a superclass method with the same signature exists. It doesn’t work in the other direction.
Can we use protected for a class in Java?
No, we cannot declare a top-level class as private or protected. It can be either public or default (no modifier).
Can protected members be accessed by objects Java?
A protected member or constructor of an object may be accessed from outside the package in which it is declared only by code that is responsible for the implementation of that object.
Why are methods protected in Java?
Protecting a constructor prevents the users from creating the instance of the class, outside the package. During overriding, when a variable or method is protected, it can be overridden to other subclass using either a public or protected modifier only.
What is protected in OOP?
Protected means that a class and its subclasses have access to the variable, but not any other classes, they need to use a getter/setter to do anything with the variable. A private means that only that class has direct access to the variable, everything else needs a method/function to access or change that data.
What is lazy class code smell?
Lazy Class smells represent classes that are under-used. If a class is rarely used, it can impede development by increasing the complexity of the codebase. Such a class might be unnecessary, and it’s functionality could be made a part of another class. Lazy Class is the opposite code smell to Large Class.
Is Lazy thread safe?
By default, Lazy
What is a lazy class?
The idea of Lazy class is simple – initialize class with action that builds or gets lazy loaded value and when value is asked then run the action if lazy loading is not happened yet.
Can abstract classes be final?
Abstract classes are similar to interfaces. You cannot instantiate them, and they may contain a mix of methods declared with or without an implementation. However, with abstract classes, you can declare fields that are not static and final, and define public, protected, and private concrete methods.
Is it good practice to make all methods public?
Yes it is very bad practice – you’re letting your tools make design decisions for you. I think the main problem here is that you’re trying to treat each individual method as a unit. This is generally the cause of all unit test woes.
Why would you make a method private?
Private methods are useful for breaking tasks up into smaller parts, or for preventing duplication of code which is needed often by other methods in a class, but should not be called outside of that class.