Ask HN: How do you regularly upgrade java libraries in huge code bases? | Hacker News Reader

Ask HN: How do you regularly upgrade java libraries in huge code bases?

3 pointsravikiranj4 comments

I'm curious as to how other companies or teams upgrade libraries in huge code bases. For my particular use case, I'm having to deal with an ancient guava java library jar (4-5 years) and any new library I try to add pulls in the latest or a much newer version than I have and wrecks havoc. At this point, I'm not sure if upgrading guava is worth it given the vast amount of code fixes that needs to be done and runtime issues that will be hard to reproduce. So, I wanted to ask how others upgrade their library jars and keep them up to date.

View on HN

It depends on the target. If this is a server, then you could potentially keep multiple copies of Guava in your lib (with different namespaces) and use the appropriate one (this will also require some jiggering with the compile flags for various modules to make sure the right one gets pulled in). It'll add a lot of bloat, but that may not matter.

If you're deploying to Android... you're kinda screwed. You can't afford the space to duplicate.

Honestly, I think the best way is the facebook/google way here - upgrade frequently and aggressively. Which might not be helpful advice after a long time of not doing exactly that.

You are spot on, upgrading frequenty and aggressively is the right way to go when the libs themselves are on the stable version. I was planning to upgrade them by release by release to avoid huge updates.

Try to avoid huge upgrades but update regularly. Create an automated process that checks at least daily if there are updates and integrate them as fast as possible. Keeping your frameworks up-to-date is important security wise.

If you use maven take a look at http://www.mojohaus.org/versions-maven-plugin . This can be integrated into a maven build and it checks if there are any new versions to your dependencies.

You should always have sufficient unit tests and integration tests for your code base. so that you can confidently upgrade all your libraries whenever you want if the tests pass.

Reply on news.ycombinator.com