Why we Cannot create the object of abstract class in Java?

We cannot instantiate an abstract class in Java because it is abstract, it is not complete, hence it cannot be used.

Is it possible to create an abstract class object using the new keyword?

Instantiation: An abstract class cannot be instantiated directly, i.e. object of such class cannot be created directly using new keyword. An abstract class can be instantiated either by a concrete subclass or by defining all the abstract method along with the new statement.

Is it possible that an abstract class can have without any abstract method?

Yes we can have an abstract class without Abstract Methods as both are independent concepts. Declaring a class abstract means that it can not be instantiated on its own and can only be sub classed.

Can we create class without object?

Static Method Static methods are the methods in Java that can be called without creating an object of class. They are referenced by the class name itself or reference to the Object of that class.

Can we create object without reference?

Simply declaring a reference variable does not create an object. For that, you need to use the new operator , as described in the next section. You must assign an object to originOne before you use it in your code.

Can abstract class have static methods?

Yes, of course you can define the static method in abstract class. you can call that static method by using abstract class,or by using child class who extends the abstract class. Also you can able to call static method through child class instance/object.

How to create object to interface or abstract class indirectly in Java?

We can create the object to interface or abstract class indirectly by using anonymous inner type. App class shows creating object to SampleInt and SampleAbs. By providing anonymous inner class to Abstract class or interface we can say they have intantiated indirectly.

Why do we declare a class as abstract in Java?

If it contains at least one abstract method, it must be declared abstract. Once a class is abstract it indicates that it may contain incomplete methods hence you cannot create an object of the abstract class. If you try to instantiate an abstract class a compile time error is generated saying “class_name is abstract; cannot be instantiated”.

Can We instantiate an object of an abstract class directly?

I know we can’t instantiate an object of an abstract class directly. You can not instantiate an abstract class or an interface – you can instantiate one of their subclasses/implementers. Examples of such a thing are typical in the use of Java Collections.

Can abstract class have instance methods that implement a default behavior?

A Java abstract class can have instance methods that implement a default behavior if we know the requirement and partially implementation we can go for an abstract class. In the above example, we cannot create the object of type Diagram but we can create a reference variable of type Diagram.