Where to place i18n key strings in Java

Question

When doing internationalization in Java, you assign a string key to each message. What\'s the best practice, on where to place those string keys. Goal is to allow easy refactori

Answer 1

String constants are the way to go. Where you define them, it really depends on your code structure and usage of keys. For example:

• If you only use the keys in one class it's best to put them there.
• If you re-use the same keys across your code, it's best to put them in a helper class (a global or per-package class depending on key usage and number of keys)

From refactoring point of view it's a bit more complicated (requires more changes) to move the constants from one class to another than to rename them or to change their value.

When changing their value you have no way of automatically change the defined resource.