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Why are virtual destructor needed?
Virtual destructors in C++ are used to avoid memory leaks especially when your class contains unmanaged code, i.e., contains pointers or object handles to files, databases or other external objects. A destructor can be virtual.
Does derived class need virtual destructor?
Note: in a derived class, if your base class has a virtual destructor, your own destructor is automatically virtual. You might need an explicitly defined destructor for other reasons, but there’s no need to redeclare a destructor simply to make sure it is virtual.
Why do we need virtual base class in hybrid inheritance?
In hybrid inheritance child class has two direct parents which themselves have a common base so data is duplicte in base class. To prevent this duplication virtual base class is needed.
Can a destructor be pure virtual?
Yes, it is possible to have pure virtual destructor. Pure virtual destructors are legal in standard C++ and one of the most important things to remember is that if a class contains a pure virtual destructor, it must provide a function body for the pure virtual destructor.
What happens if virtual destructor is not used?
If your base class destructor is NOT virtual then only base class object will get deleted(because pointer is of base class “Base *myObj”). So there will be memory leak for derived object.
What happens if a base class has a virtual destructor?
Virtual Destructor. Deleting a derived class object using a pointer to a base class that has a non-virtual destructor results in undefined behavior. To correct this situation, the base class should be defined with a virtual destructor.
Why do we need virtual destructors in C + +?
Constructor is actually not part of the interface because object is always instantiated explicitly. A class destructor is a function with same name of the class preceding with ~ that will reallocate the memory that is allocated by the class. Why we need a virtual destructor
When to call base class destructor in C + +?
Destructors in C++ automatically gets called in the order of their constructions (Derived then Base) only when the Base class destructor is declared virtual. If not, then only the base class destructor is invoked at the time of object deletion. It is recommended to declare base class destructor as virtual otherwise, it causes undefined behavior.
When to use a non-virtual destructor in Java?
A non- virtual destructor signifies that a class should not be used as a base-class. Will having a non- virtual destructor of a derived class act like a weak form of the Java final modifier? I am especially interested in the case where the base class of the derived class has a virtual destructor.