Re: RE: AS400 ToolBox for Java - Record locking

["David Morris" <dmorris@xxxxxxxxxxxxx>]

Frank,

I don't know if there is a Java class that allows you to specify record locks, 
but 
this is not a requirement for multi-user systems.  SQL dos not support this 
except 
through commitment control.  You can easily simulate a simple lock by comparing 
the record at update with an image saved when the record was read.  Or, you can 
use an update count in the record to accomplish this.  If what you want is 
to make sure that a set of records is updated, commitment control would be 
the best method.

If what you really want is to lock a record without a subsequent update, I 
would add 
a field that contains the "lockers" id and a method to clear the lock, after 
verification, 
without outside involvement.  You don't want to have to run a fix in the event 
of a 
power failure, etc.

David Morris

>>> "David Murphy" <murphy_d@oscar.ossc.state.or.us> 11/16 2:19 PM >>>
Good luck, Frank! I subscribed to this list over a week ago and yours is the 
first message I've seen!


David Murphy
Information Services
Oregon State Scholarship Commission
1500 Valley River Drive
Eugene, OR 97401
(541) 687-7433


-----Original Message-----
From:   owner-java400-l@midrange.com  On Behalf Of DeSarro Frank
Sent:   Monday, November 16, 1998 8:25 AM
To:     JAVA400-L@midrange.com 
Subject:        AS400 ToolBox for Java - Record locking

        I'm new to this mailing list.  I apologize if this question has been   
asked previously.  I'm trying to lock a record using the record level   
access classes included in the Toolbox.  I can not find anything in the   
Toolbox documentation to set a record lock using the record level access   
classes.  Is there a way to lock a record using the record level access   
classes?  I know using sequential access you can lock a number of bytes,   
but sequential access is not what I want.  I don't want to lock the file   
either.  Any help with this matter would be greatly appreciated.  A   
record lock to me would seem to be a rather standard operation needed to   
process data in a multi-user system.  If the answer to this question is   
obvious, just point me to where in the documentation this is explained   
and I'll figure it out.  Thanks.
   Frank DeSarro

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