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Re: java doubts

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  To: comp.lang.java.databases
On Tue, 8 Jul 2008 06:13:04 -0700 (PDT), amarmca2u@gmail.com wrote,
quoted or indirectly quoted someone who said :

>what we call a concrete class in java api with out constructors(Like
>DriverManager)?

Class with private or protected constructor.

>detail data about protected constructor. Can we have protected class?
Try the experiment.

>why all exception classes implementing the serialzible interface?
It was possibly for a program like Lotus Ensuite, that could save the
program state, do something else, then pick up where it left off.  It
used serialisation to encapsulate the entire state of the app.
The other reason is it was easy to do.  Exceptions don't have much
inside them.

>what is the difference between the "A class by defaultly
>synchronized(Vector)" and "A class which is manuvally synchronized"?
It is the difference between using Vector and ArrayList+
Collections.synchronizedCollection( a ); 

or Hashtable and HashMap + Collections.synchronizedCollection( a );

or doing the threading manually, only where needed.

see http://mindprod.com/jgloss/arraylist.html#THREADSAFETY

Normally you have onely one thread, so there is no point in the sync
overhead.
-- 

Roedy Green Canadian Mind Products
The Java Glossary
http://mindprod.com

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java doubts "amarmca2u" <amarmca2u@THRWHITE.remove-dii-this> - 2011-04-27 15:22 +0000
  Re: java doubts "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 15:22 +0000
  Re: java doubts "=?ISO-8859-1?Q?Arne_Vajh=" <=?iso-8859-1?q?arne_vajh=@THRWHITE.remove-dii-this> - 2011-04-27 15:22 +0000
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