What are different types of Classes available in Java?

Different types of Classes available in Java are as follows:

1. Concrete class
2. Abstract class
3. Final class
4. Static class
5. Inner Class

Concrete class

In Java, A concrete class is a type of subclass, which implements all the abstract methods of its super abstract class from which it extends.

Abstract class

In Java, An abstract class is a type of class. An abstract class is declared by the abstract keyword. An abstract class cannot be instantiated directly. An abstract class can be instantiated either by a concrete subclass or by defining all the abstract methods along with the single statement that has no definition or body. It may or may not contain an abstract method. If a class contains an abstract method, then it also needs to be an abstract method.

Final class

A class declared with the final keyword is a final class and it cannot be extended by another class.

Static class

Static classes in Java are allowed only for inner classes which are defined under some other class,as static outer class is not allowed which means that we can't use static keywords with outer class.

Inner Class

A class declared within another class or method is called an inner class.