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implementing an interface without methods  RSS feed

 
Greenhorn
Posts: 3
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How is it possible for a class to implemnt an interface that
has no methods defined?

I've done this successfully.....

Is there some "play" with the java.lang.Object and therefore by
default there is ALWAYS a conract or what?
 
Ranch Hand
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Hi Kambiz,

Java does not require that an interface contain any methods. When an interface does not specify any methods, any implementing classes will automatically satisfy the interface. This is often used with "marker" interfaces, such as Serializable.
 
Greenhorn
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Hi Kambiz,

An interface may or may not have any methods in it.

If at all it has any methods, they are public abstract by default and any non-abstract class implementing it should provide the method implementation for all the methods available.
 
It is sorta covered in the JavaRanch Style Guide.
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