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Inner classes

 
Greenhorn
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Is the below statements are true?
"An abstact class must declare at least one abstract method"
"A local class can be declared abstract."
 
Ranch Hand
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You are right on both counts. In fact, local inner class can be declared only abstract or final. It can't be declared public, protected, private etc.
Rattan
 
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"An abstact class must declare at least one abstract method"


False.
If the class contains 1 or more abstract methods, it must be declared abstract, but it is not required that a class contain an abstract method to be declared abstract.

"A local class can be declared abstract."


True.
An Inner Class isn't really that different from a top-level class - they can be abstract.
I hope that helps,
Corey
 
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hi majohnad
"An abstract class must declare at least one abstract method"
I make sure that the above statement is false
because abstract class can contains no abstract method.For example MouseAdapter or KeyAdapter.
 
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An abstract class does not have to have any abstract methods, or any methods at all, but must be declared abstract if it has any abstract methods.
A method-local class (which is not an anonymous class) can be abstract. It can also be final or strictfp. No other modifiers are allowed, because such a class cannot be accessed from the outside, so the other modifiers make no sense.

[ April 21, 2003: Message edited by: Roger Chung-Wee ]
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