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Empty abstract classs vs Empty interface

 
A Kumar
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whats a difference between an empty abstract classs and an empty interface?

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fred rosenberger
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In a single class, you can implement as many interfaces as you want, but you can only inherit from one abstract class.
 
A Kumar
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A friend of mine was asked this question and she replied the same as you mentioned. But he wasnt satisfied. So is there more to it than just one explanation.
 
Paul Clapham
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Who wasn't satisfied? Your friend is "she" so this "he" is a third person. Seems to me that's the person you should be asking.
 
Ernest Friedman-Hill
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Well, an empty interface has a special name (a "marker interface"), and the JDK contains a number of examples of how they used to be used, back before annotations were introduced in Java5. An empty abstract class -- well, that's just dumb
 
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