First, I assume you meant to code “implements LogLevelStrength” instead of
“extends LogLevelStrength” since an enum already implicitly extends Enum and a
Class (or Enum) can’t extend an Interface.
Second, doing this would mean that the Log4j 2 core would have to be modified
to never use the Level enum and only use the Interface, except perhaps in
ThresholdFilter which can really only be configured with one of the Level enum
values. Not being able to use Level as a method parameter and field in the
LogEvent makes its value as an enum minimal. Only being able to use Level
values in the ThresholdFilter means anyone with a custom Level has to write
their own custom Level Filter.
I think providing the extra levels is a fair compromise.
Ralph
On Jan 21, 2014, at 8:50 AM, Paul Benedict <pbened...@apache.org> wrote:
> Or if you really want to get fancy (!!!), don't make the log4j API accept an
> Level, but an interface that each logging level Enum object implements. Then
> programmers can use enums. Example:
>
>
> public interface LogLevelStrength {
> int getStrength();
> }
>
> public enum Level extends LogLevelStrength {
> FATAL() {
> public int getStrength() { return 600; }
> }
> ...
> }
>
> public enum MyCustomLevel extends LogLevelStrength {
> DIAGNOSTIC() {
> public int getStrength() { return 250; }
> }
> ...
> }
>
>
>
> On Tue, Jan 21, 2014 at 10:45 AM, Paul Benedict <pbened...@apache.org> wrote:
> It won't be possible with an enum, yes, but we should have a way to allow
> extensions. For example, if we publically document the integer level of the
> enums (separated by 100), then we can provide an overload that accepts an
> integer. That's how you can allow people to slide in their extensions.
> Philospohy: enums for the standard, ints for the custom programmer.
>
> Paul
>
>
> On Tue, Jan 21, 2014 at 10:42 AM, Gary Gregory <garydgreg...@gmail.com> wrote:
> On Tue, Jan 21, 2014 at 11:33 AM, Paul Benedict <pbened...@apache.org> wrote:
> On Tue, Jan 21, 2014 at 10:25 AM, Ralph Goers <ralph.go...@dslextreme.com>
> wrote:
>
> I tend to agree that there is ambiguity between TRACE and VERBOSE, but I have
> no problem adding it if it means end users will have more flexibility with
> little cost.
>
>
> I think this is meaningless flexibility. It smells of adding a feature
> without a good reason. Imagine the conversations people will have to explain
> the difference between TRACE and VERBOSE. I can't think of any good universal
> justification for its use that demands an addition to log4j.
>
> If you do not like it, do not use it ;)
>
> This is best reserved for a personal extension.
>
> Which is not possible since Level is an enum, hence this discussion before
> the API freezes.
>
> Gary
>
>
>
>
>
> --
> E-Mail: garydgreg...@gmail.com | ggreg...@apache.org
> Java Persistence with Hibernate, Second Edition
> JUnit in Action, Second Edition
> Spring Batch in Action
> Blog: http://garygregory.wordpress.com
> Home: http://garygregory.com/
> Tweet! http://twitter.com/GaryGregory
>
>
>
> --
> Cheers,
> Paul
>
>
>
> --
> Cheers,
> Paul
