Interface- concept and keyword

Interface- concept and keyword

alsalam 03 Apr 2009 16:16

The concept of interface is that we have a set of behavior that an
implementing class is supposed to provide, after which we can use all
such classes and their objects similarly as we know that the behavior is
available.
For example, if we have a Drawable interface that defines a method
draw(), then if our Player class and our Ball class both implement the
interface, we can add them to an array of Drawable and just send the
array to the paint method to draw.

The keyword interface is used like
interface SomeInterface
{
void aMethod();
…
}

and when implemented, something like

class SomeClass implements SomeInterface
{
void aMethod();
…
}

Re: Interface- concept and keyword

jbschafer 13 Apr 2009 14:51

So no one is going to point out the flaws in this post???

Re: Interface- concept and keyword

fahrmans 14 Apr 2009 02:47

Let me have at this one.
The interface contains the behavior that a class is required
to implement when the class implements the interface.
The interface would look about how it does above.
public interface SomeInterface
{
//Methods required in implementation
public void aMethod(int somenum);
public void anotherMethod(boolean isit);

}

and the class that implements would need to look a little like this

public class SomeClass implements SomeInterface
{
//Methods required in implementation
public void aMethod(int somenum)
{
//implementation goes here
}
public void anotherMethod(boolean isit)
{
//implementation goes here
}

}

Re: Interface- concept and keyword

larrysavago 15 Apr 2009 19:13

… to make this an abstract class you would chage
"public class" to "abstract class" and write atleast one method as…

abstract void abstractMethod();

and then you extend the abstract class?? and…

define the abstract method?

public void abstractMethod()
{
// type stuff here!
}

Is this right for abstract classes?