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Abstract method  RSS feed

 
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http://www.examulator.com
link question

What will happen when you attempt to compile and run the following code?


1) Compile time error, synchronized can only be used in a class that extends Thread
2) Compile time error, malformed method getFireStation in class Hall.
3) Compilation and output of opposite at runtime
4) Compile time error, code within main method is incorrect.

Answer is 3.Abstract method is implemented in subclass with synchronized on it.what is the use of this manner?This is the first time i have got questions in absract method like this? In what other ways of abstract method implemented in subclass in different ways?Please guide me.
 
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A non synchronized method can be override to synchronized and vice versa.
 
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Synochronized modifier is used to make a method accessible to only one thread at a time. This is done by obtaining a lock on a object from which that method was invoked. Any other thread is denied to access that method using SAME object.

You'll learn more about synchronization in THREADS.
 
It is sorta covered in the JavaRanch Style Guide.
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