Java: getting strings from enum without having to call .toString()?

Question

Say I have this enum:

public class MyErrors {
    public enum Errors {
        BAD_FILE_PATH("Please point to a valid file");

        private final String message;

        Errors(final String message) {
            this.message = message;
        }

        @Override
        public String toString() {
            return message;
        }
    }

And this call:

Logging.log(Level.INFO, MyErrors.Errors.BAD_FILE_PATH.toString());

It seems so verbose to me to have to call .toString(). Isn't there a way to just call the enum itself and have it return its string by default?

Ideally I'd like something like MyErrors.BAD_FILE_PATH --> which returns a string so it's not so verbose. Does that make any sense?

Sure. _Don't use an enum._ Provide, instead, a static final String. — Louis Wasserman, Nov 16 '17 at 20:58
First time I have ever heard of calling `toString` is considered verbose — Trash Can, Nov 16 '17 at 21:01
Why are you trying to use an enum for something that clearly isn't? — Nir Alfasi, Nov 16 '17 at 21:01
@Dummy actually calling toString *is* verbose, I don't remember doing so over the past few years: if you want to print an object you can simply print the object (which will implicitly call its toString method). — Nir Alfasi, Nov 16 '17 at 21:06
@alfasin but using an object as an argument in a method doesn't mean to call toString() implicitly. — UninformedUser, Nov 16 '17 at 21:07
@AKSW why call its toString? pass the object and let the other method figure it out. — Nir Alfasi, Nov 16 '17 at 21:09
Which is obviously not implemented in that way in the underlying logging framework...Anyways, I don't see any problem here. In the worst case, add a method `msg()` to the enum and call this, although it's still necessary to call a method. — UninformedUser, Nov 16 '17 at 21:10
see https://stackoverflow.com/questions/13291076/java-enum-why-use-tostring-instead-of-name — Laurent Perez, Nov 16 '17 at 21:37

robertf · Answer 1 · 2017-11-17T02:52:42.090

Both of these work for me in Eclipse:


    LOG.info(Errors.BAD_FILE_PATH);   // Using Log4j
    System.out.println(Errors.BAD_FILE_PATH);

These two methods take an Object parameter. And since are not receiving Strings, the logic in those methods must call the toString() method on the passed in object to obtain a string.

The log() method of java.util.logging.Logger does not support an Object parameter. Instead, it is expecting a String parameter; thus, the logic in this method has no need to call toString().

What you are looking for is a new signature for the Logger that supports an Object parameter. However, I don't know that extending the Logger is a straight forward process or advisable; see here.

Another option would be to use Log4j.

I'm using import java.util.logging.Logger, and using the first signature of (Level level, String message). I get "cannot resolve method 'log'" if I don't have the .toString... so full code looks like LOGGER.log(Level.INFO, ErrorMessages.Errors.STARTED.toString()); — Aaron, Nov 17 '17 at 00:25

Java: getting strings from enum without having to call .toString()?

1 Answers1