What is the best way to manage configuration data

Question

I am working on a product suite which has 4 products. Right now, all of the configuration data is either in the XML or properties files.This approach is not maintainable as

Answer 1

There are plenty of different strategies. All of them are good and depends on what suit you best.

1. Build a single artifact and deploy configs to a separate location. The artifact could have placeholder variables and, on deployment, the config could be read in. Have a look at Springs property placeholder. It works fantastically for webapps that use Spring and doesn't involve getting ops involved.
2. Have an externalised property config that lives outside of the webapp. Keep the location constant and always read from the property config. Update the config at any stage and a restart will be up the new values.
3. If you are modifying the environment (i.e. application server being used or user/group permissions) look at using the above methods with puppet or chef. Also have a look at managing your config files with these tools.