Can there be 2 main methods in Java?

Inhaltsverzeichnis:

1. Can there be 2 main methods in Java?
2. Is delete a keyword in Java?
3. Why is main method void in Java?
4. Can we call method from constructor?
5. Can we override final method?
6. Can we call final method in Java?
7. Can you use this () and super () both in a constructor?
8. What is this () in Java?
9. Can constructor be overridden?
10. Why constructor is public in Java?
11. Can constructor be virtual?
12. Can constructor be virtual in Java?
13. Can we have virtual destructor justify?
14. Can abstract class have constructor C++?

Can there be 2 main methods in Java?

The only way to have two main methods is by having two different classes each with one main method. The name of the class you use to invoke the JVM (e.g. java Class1, java Class2) determines which main method is called.

Is delete a keyword in Java?

Ans. No, delete is not a keyword in Java.

Why is main method void in Java?

The main() method is static so that JVM can invoke it without instantiating the class. ... Void: It is a keyword and used to specify that a method doesn't return anything. As main() method doesn't return anything, its return type is void. As soon as the main() method terminates, the java program terminates too.

Can we call method from constructor?

Calling a method using this keyword from a constructor Yes, as mentioned we can call all the members of a class (methods, variables, and constructors) from instance methods or, constructors.

Can we override final method?

Can We Override a Final Method? No, the Methods that are declared as final cannot be Overridden or hidden. ... It is noteworthy that abstract methods cannot be declared as final because they aren't complete and Overriding them is necessary.

Can we call final method in Java?

We can declare a method as final, once you declare a method final it cannot be overridden. ... So, you cannot modify a final method from a sub class. The main intention of making a method final would be that the content of the method should not be changed by any outsider.

Can you use this () and super () both in a constructor?

We can use super() as well this() only once inside constructor. If we use super() twice or this() twice or super() followed by this() or this() followed by super(), then immediately we get compile time error i.e, we can use either super() or this() as first statement inside constructor and not both.

What is this () in Java?

The this is a keyword in Java which is used as a reference to the object of the current class, with in an instance method or a constructor. Using this you can refer the members of a class such as constructors, variables and methods. Using “this” you can −

Can constructor be overridden?

Constructor looks like method but it is not. It does not have a return type and its name is same as the class name. But, a constructor cannot be overridden. If you try to write a super class's constructor in the sub class compiler treats it as a method and expects a return type and generates a compile time error.

Why constructor is public in Java?

You make a constructor public if you want the class to be instantiated from any where. You make a constructor protected if you want the class to be inherited and its inherited classes be instantiated. ... Example of usage of private constructor is singleton design pattern.

Can constructor be virtual?

The virtual mechanism works only when we have a base class pointer to a derived class object. In C++, the constructor cannot be virtual, because when a constructor of a class is executed there is no virtual table in the memory, means no virtual pointer defined yet. So, the constructor should always be non-virtual.

Can constructor be virtual in Java?

If it is like virtual function in C++ there is no virtual constructor in java. Not that I'm aware off. ... All you have to do is simply set the constructor to private, and within the class, include a static method that creates the class object instance and returns it.

Can we have virtual destructor justify?

Destructors in the Base class can be Virtual. Whenever Upcasting is done, Destructors of the Base class must be made virtual for proper destrucstion of the object when the program exits. NOTE: Constructors are never Virtual, only Destructors can be Virtual.

Can abstract class have constructor C++?

An abstract class can have a constructor similar to normal class implementation. In the case of the destructor, we can declare a pure virtual destructor.