Interface is the framework for methods . where only mehod signature and there is no implementation of a method.In Interface every method is abstract method.
In abstract class there abstract method signature is available and which class extend this super
class has to implement this abstract method.

1)Abstract class is a collection of abstract methods and concrete methods or only abstract methods or only concrete methods
Interface is a collection of only abstract methods
2)the members of the abstract class are public(default),protected,static
the members of interface are implicitly public
3)A class can inherit one or more interfaces but a class can inherit only one abstarct class
4)abstract class can add more functiuonality without destroying the child classes
in an interface..creation of additional functions will have an effect on its child class due to necessary implementation of interface methods in child class

I love Jave

abstract class is a signature of class, can't be instantiated .
it having some abstract members(both variables and methods) which are get implemented in to derived classes
Interface is heaving all its methods (no any veriables) without implemented and all its methods are defaultly public because they all get implemented in derived classes but in abstract class only some its members may public

1) abstract class may or maynot be contain abstract methods,but interfaces must contain abstract methods only
2)abstract class contains both abstract and concrete methods,concrete methods contain static,final and ordinary methods.
3)abstract class contains all concrete or all static methods or all final methods or all abstract methods or combination of all the above.
4)interface tells us what to do?,but not how to do
5)both abstract class and interface particpates in object creation through the concept of dynamic binding.

both are same but we can implements one or more at a time but we can extend one class at a time

Interface:

>It contains only abstract methods .
>it contains only constants but not instance variables.

abstract:

>it contains some abstract methods or concrete methods .
>it contains only instance variables.

hi

Is java predefined or user-defined language ??
Can u please help me out. thanq

Hi,

An interface is called as a pure abstract class where non abstract member functions are not allowed but in case of abstract classes we can have both abstract and non abstract member functions based on the requirement...

a) All the methods declared inside an interface are abstract whereas abstract class must have at least one abstract method and others may be concrete or abstract.

b) In abstract class, key word abstract must be used for the methodsWhereas interface we need not use that keyword for the methods.

c)Abstract class must have subclasses whereas interface can’t have subclasses.