Hibernate

Using MySQL Collations in Java

I’ve recently discovered Stackoverflow as a nice pass-time on the one hand and as a valuable source for answers on the other hand. Normally it takes only a few minutes to get answers for most questions. However, I managed to ask a question that nobody was able to answer yet. The question was about Collations. As I’m suspecting that Collations are a Java feature that is hardly used, I kept working on the problem myself rather then just waiting for an answer on Stackoverflow.

I’ve managed to get something working right now. It’s not completely tested but it should work quite well. What I’m doing is the following: I parse the charset files of MySQL (on an Ubuntu system, you can find them in /usr/share/mysql/charsets/) and do the collation based on those files myself rather than using Java’s built-in collations.

EDIT: I’ve just created a github project that’s available as a Maven artifact from Sonatype’s OSS repository.


Detaching and Attaching Persistent Objects on Serialization

Today I’ve received a mail by someone interested in a serialization mechanism I described some days ago. This mechanism was implemented to avoid dealing with detached Hibernate objects in different HTTP (i.e. Wicket) requests (it’s not restricted to Hibernate though). The idea is quite simple: detach objects if they are persistent, serialize them if they are transient, deserialize and attach for the next request – all transparently. So far, this isn’t very special and doesn’t justify such a complicated approach. However, it’s the only way of attaching and detaching object graphs that consist of transient and persistent objects I know.
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