What is Diamond problem and how is it resolved in Java?
The solution to the diamond problem is default methods and interfaces. The default method is similar to the abstract method. The only difference is that it is defined inside the interfaces with the default implementation. We need not to override these methods. Because they are already implementing these interfaces.
What is the Diamond problem and how is it solved?
Virtual inheritance solves the classic “Diamond Problem”. It ensures that the child class gets only a single instance of the common base class. In other words, the Snake class will have only one instance of the LivingThing class. The Animal and Reptile classes share this instance.
What is the problem with multiple inheritance in Java?
Java does not support multiple inheritance because of two reasons: In java, every class is a child of Object class. When it inherits from more than one super class, sub class gets the ambiguity to acquire the property of Object class.. In java every class has a constructor, if we write it explicitly or not at all.
What are the disadvantages of multiple inheritance?
The disadvantage of multiple inheritance is that it can lead to a lot of confusion(ambiguity) when two base classes implement a method with the same name.
What’s the diamond problem?
The “diamond problem” (sometimes referred to as the “Deadly Diamond of Death”) is an ambiguity that arises when two classes B and C inherit from A, and class D inherits from both B and C. It is called the “diamond problem” because of the shape of the class inheritance diagram in this situation.
What is ambiguity problem in Java?
The ambiguities are those issues that are not defined clearly in the Java language specification. The different results produced by different compilers on several example programs support our observations. KEY WORDS: Java; language design; language. definition; object-oriented programming; 1.
What is Diamond problem in C++?
The diamond problem occurs when two superclasses of a class have a common base class. For example, in the following diagram, the TA class gets two copies of all attributes of Person class, this causes ambiguities.
What is class polymorphism?
Polymorphism means “many forms”, and it occurs when we have many classes that are related to each other by inheritance. Like we specified in the previous chapter; Inheritance lets us inherit attributes and methods from another class. Polymorphism uses those methods to perform different tasks.
What is virtual void in C++?
When you refer to a derived class object using a pointer or a reference to the base class, you can call a virtual function for that object and execute the derived class’s version of the function.
Why is multiple inheritance bad?
Multiple inheritance in languages with C++/Java style constructors exacerbates the inheritance problem of constructors and constructor chaining, thereby creating maintenance and extensibility problems in these languages. Modern way of resolving this to use interface (pure abstract class) like COM and Java interface.
Why is inheritance bad?
Inheritance is not the core of object oriented programming, and it is commonly overrated because it creates more harm than help and should only used in certain situations.
Is multiple inheritance allowed in Java?
The Java programming language supports multiple inheritance of type, which is the ability of a class to implement more than one interface. As with multiple inheritance of implementation, a class can inherit different implementations of a method defined (as default or static) in the interfaces that it extends.
What are the disadvantages of inheritance?
Main disadvantage of using inheritance is that the two classes (base and inherited class) get tightly coupled. This means one cannot be used independent of each other. If a method is deleted in the “super class” or aggregate, then we will have to re-factor in case of using that method.
Why do we do multiple inheritance?
Multiple Inheritance is a feature of object oriented concept, where a class can inherit properties of more than one parent class. On calling the method, the compiler cannot determine which class method to be called and even on calling which class method gets the priority. Why Java doesn’t support Multiple Inheritance?