Actual use of interface in java other than multiple inheritance

[Saaz]

Hi All,

I am IT student, I have lots confusion regarding java interfaces.

What is the actual use of interface in java apart other than multiple inheritance?

I don't have idea about why sun-java included the interface concept.

Can anybody of you provide information regarding use of interfaces?

Please help me in this...

[Zecho]

The one of essential use of the interface is to relate classes from different types of hierarchy.

See the below example:

for this example, lets take 2 classes:

public abstract class Vegetable {
}
public class Tomato extends Vegetable {
}
public abstract class Car {
}
public class Mercedes extends Car {
}

There is no common content between above classes.

but above two classes might be washed. so you are able to declare an interface 'washable'.

public interface Washable {
void wash();
}

then implement this in the two abstract classes.
now, suppose if you have a program with both Car objects and vegetable objects, and you have to wash them, you can use:

List<Washable> objectsToWash = new Arraylist<Washable>();
for(Washable washableObject: objetsToWash){
washableObject.wash();
}

Above may help you in your problem.

[Reegan]

Hi,

For you kind information in java multiple inheritance is not available.
But in most cases multiple inheritance plays the important role,that's why they introduced interface as a subsidiary for multiple inheritance.

Class and interfaces are similar in nature. But the only difference is that you can't create anything within interfaces, And also we can not create instances for them.

I hope this details is able to solve you confusion....

[opaper]

Hi guys,

I am not expert in the java programming. But this is you understanding that we can implement Multiple Inheritance in java programming.

The main use of interface is to implement the abstract class. We are not able to create anything in interface.

This is all which I know..