Avoid violation of DRY with ternary?

问题

Here's what I have.

Map data = new HashMap<>(); // assume this has been populated

public int getLastestVersion() {
    // data.get("PATH_TO_DESIRED_POINT") would be an integer
    return data.get("PATH_TO_DESIRED_POINT") == null ? 0 : (int)data.get("PATH_TO_DESIRED_POINT");
}

I'm trying to avoid violating DRY, but I want to be able to keep the simplicity of the ternary. Is there something I can do?

回答1:

If you are using Java8, you can use getOrDefault method:

return data.getOrDefault("PATH_TO_DESIRED_POINT", 0);

回答2:

You could assign the result to a final local variable. That way the compiler is free to inline it, and you don't have to repeat the calls to get in your Map<String, Integer> data. In Java 8+, something like

final Integer v = data.get("PATH_TO_DESIRED_POINT");
return v != null ? v : 0;

来源：https://stackoverflow.com/questions/33358468/avoid-violation-of-dry-with-ternary