db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Knut Anders Hatlen (JIRA)" <j...@apache.org>
Subject [jira] Commented: (DERBY-2921) Replication: Add a network service that connects the master and slave Derby instances
Date Thu, 27 Sep 2007 09:01:53 GMT

    [ https://issues.apache.org/jira/browse/DERBY-2921?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12530660

Knut Anders Hatlen commented on DERBY-2921:

Shouldn't ReplicationMessage.readExternal() throw an exception if the version is incorrect?
As it is now, it checks the version and just leaves all fields as null values if it is incorrect.
I think the appropriate exception is java.io.InvalidClassException (sub-class of IOException).

I'm not sure the version check in parseInitiatorMessage() works. If the version is incorrect,
ReplicationMessage.getMessage() will return null. That means this line fails with a NullPointerException:

        //Get the UID of the master
        long masterVersion = ((Long)initiatorMessage.getMessage()).longValue();

So we never get to the point where we actually check the version.

By the way, do we need 8 bytes (a long) to represent the version, or would a smaller data
type suffice?

> Replication: Add a network service that connects the master and slave Derby instances
> -------------------------------------------------------------------------------------
>                 Key: DERBY-2921
>                 URL: https://issues.apache.org/jira/browse/DERBY-2921
>             Project: Derby
>          Issue Type: Sub-task
>          Components: Services
>    Affects Versions:
>            Reporter: Jørgen Løland
>            Assignee: V.Narayanan
>         Attachments: Replication_Network_expln_v6.txt, Replication_Network_v1.diff, Replication_Network_v1.stat,
Replication_Network_v10.diff, Replication_Network_v10.stat, Replication_Network_v2.diff, Replication_Network_v2.stat,
Replication_Network_v3.diff, Replication_Network_v3.stat, Replication_Network_v4.diff, Replication_Network_v4.stat,
Replication_Network_v5.diff, Replication_Network_v5.stat, Replication_Network_v6.diff, Replication_Network_v6.stat,
Replication_Network_v7.diff, Replication_Network_v7.stat, Replication_Network_v8.diff, Replication_Network_v8.stat,
Replication_Network_v9.diff, Replication_Network_v9.stat
> A network connection is required between the master and slave Derby instances of a replicated
database. The connection will be used to send many kinds of messages, including:
> * log records
> * the database (when replication is started)
> * master -> slave commands (like "stop replication")

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message