-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Khin, Gerald wrote: > > Is it planned to support multiple systems in the same VM? Think of two > or more java libraries from different companies each using derby as > embedded database. I guess that they will hamper each other.
Technically derby supports a single system, which can comprise of multiple databases, per class loader in a single JVM. Typically the Derby libraries are on the class path and thus are loaded by the system class loader leading to a single system per JVM. Database instances can only be loaded by one Derby system. Derby also supports (or will support once the first release with new features is available) "soft-upgrade", allowing an application to use a newer version of the engine without upgrade. Thus if two Derby applications are running in a single JVM, one intended to run against 10.0 and one against 10.5, then the JVM can use the single 10.5 Derby engine for both databases and applications. Since Derby is just a jar file in embedded mode, it is like two applications trying to use two different versions of a jar. Dan. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFBZJsAIv0S4qsbfuQRAkJaAKCyIp/FoAyWwk9Wv2nXVK09XT0p6gCg4iKa IEEH8Aal9DmvpfcLtgVXXPc= =W7UR -----END PGP SIGNATURE-----
