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

I also think the first is the worst choice. In most cases (the key is only used by one class) I would prefer the second solution with String constants.

If the key is referenced from more than one class, the neighbor class is a better way (using an interface like @moohkooh mentioned).

The solution with one central class creates a dependency magnet which is a bad design in my opinion. Neighbor interfaces with constants per package would be a better one.

If you do not want a interface to hold the constants, you can use an enriched enum:

public enum DESCMessage {

  HELLO("hello_key"),
  OTHER("other_key");

  private final String key;

  private DESCMessage(String key) {
    this.key = key;
  }

  public String key() {
    return key;
  }
}

This can be used as:

messages.getString(DESCMessage.HELLO.key());