Abstract Class in Java

All the methods declared inside an Interface are abstract. Where as abstract class must have at least one abstract method and others may be concrete or abstract. In Interface we need not use the keyword abstract for the methods.

1) we can't create object of abstract class.
2) we can declare a variable.
3) we can make normal method and abstract method.
4) we can't make method body with abstract method.
5) in derived class we can use abstract method by override keyword.
6) we can't use multiple inheritance in abstract class.
7) Absrtact class can be extended by only one class;Interface can be implemented by more than one class;
ie. class can inherit only one abstract class
8)Abstract classes can inherit interfaces while interfaces cannot inherit abstract classes but class can implement more than one interface.
9) The members of the interface are public with no implementation. Abstract classes can have protected
parts,static methods, etc.
10)An abstract class can contain fields, constructors, or destructors and implement properties. An
interface can not contain fields, constructors, or destructors and it has abstractmethod,property's signature
but no implementation etc.