Why I must override clone if i want cloneable class? All classes extends from Object, so why I must override the Object clone method? Why I cant just invoke the original Object clone method?
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Shelef
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You might want to checkout this answer as well: http://stackoverflow.com/questions/3652748/cloning-objects-in-java-3-questions/3652767#3652767 – nkr Mar 18 '13 at 12:55
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You can always write a copy method in your class. You don't have to override anything. – Gilbert Le Blanc Mar 18 '13 at 13:03
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It's one of the many "design flaws" in the JDK.
Clonable should have been an interface with a clone() method, but instead it's a marker interface and Object has a "do nothing" implementation of the clone() method... and you're left with your question.
If you're interested, this answer lists some other "mistakes" in java.
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See here: http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Cloneable.html
Invoking Object's clone method on an instance that does not implement the Cloneable interface results in the exception CloneNotSupportedException being thrown.
Also I guess this discussion would be helpful for you: Confusion about cloneable interface and object.clone() in java
