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org.w3c.tools.dbm

From: Anselm Baird-Smith <anselmb@eng.sun.com>
Date: Wed, 30 Jun 1999 09:03:03 -0700 (PDT)
To: kabir@our.st
Cc: jigsaw <www-jigsaw@w3.org>
Message-ID: <14202.16182.514774.557980@gaston>

This package really is a java port of gdbm (same algorithms, etc). 

kabir@our.st writes:
 > Question regarding jdbm class:
 > 
 > Is this implementation thread safe?  I've noticed that bucket lookups are synchronized, but I am not clear whether this guarantees thread-safety (or rather data integrity).  

It should be, the jigsaw is MT and uses it quite a bit ;-) Some
methods are *intentionnally* not synchronized (for performance
reasons)

 > I have also noticed some of the commented caveats in the jdbmBucket.java -- for example in jdbmBucket.add() regarding bucket splits -- but unfortunately I am not exactly clear on what actions would create such conditions.

Can't remember what the comment says ;-)

 > Please note that I intend to use only the exposed jdbm interface and would not directly utilize (or subclass) the support classes; and that the objects that I am writing will guarantee that at any given time, only one thread will take destructive (w/u/d) action for a given key.

That's the way it should be used

 > I would also greatly appreciate any information regarding usage and performance considerations (threading, file size caps, performance tweaks, etc.) for this class.  (I am aware of the key Enumeration issue.)

I;'ve probably done some of that testing, but nothing was ever written 
about it. In general it should behave similarly to gdbm

Anselm.
Received on Wednesday, 30 June 1999 12:06:25 GMT

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