Ralph,
Perhaps you're misunderstanding or I was unclear (let's say it's the
latter).
The interface is only so you can allow custom log levels as an enum. The
client code could still use the enums you provided today. All that's
changing is the API signatures to accept the interface -- which
conveniently all the enums would implement. As I said,
FATAL/ERROR/INFO/WARN/DEBUG/TRACE would implement the interface.
It's worth considering this because I think we're about to pollute log4j
with logging levels that really don't belong in the public api. These are
definitely custom things people should implement themselves.
Paul
On Wed, Jan 22, 2014 at 12:33 AM, Ralph Goers <ralph.go...@dslextreme.com>wrote:
> 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
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>>> Blog: http://garygregory.wordpress.com
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>>>
>>
>>
>>
>> --
>> Cheers,
>> Paul
>>
>
>
>
> --
> Cheers,
> Paul
>
>
>
--
Cheers,
Paul
