Hi Michael,
At 09:44 PM 8/31/2006, Newcomb, Michael-P57487 wrote:
>What is going on? I think LOGBack came from the ULogger stuff, but I am
>not sure
No, logback is based on several years of work done on log4j, although
closely related, logback did not come from ULogger/UGLI/SLF4J.
>Can I get a quick briefing as to what happened? Why the split form Log4J,
>etc..?
Logback incorporates many improvements which we hope developers will
find very useful. We unfortunately could not get our architectural
changes into log4j. In order to keep innovating, instead of evolving
log4j we had to go through a revolution in the form of logback. The
split was necessary to ensure the continued success of log4j/logback.
>All I want is a stable logging API
SLF4J provides part of the answer. Sebastien and I, are working on an
log4j-slf4j bridge, similar to the existing jakarta commons logging
(JCL) to SLF4J bridge. Users who currently log through the log4j API
can keep their existing log statements (without change). The bridge
will redirect the log4j calls to slf4j which will in turn delegate to
another logging system such as logback or log4j or even
java.util.logging (JUL).
Graphically, this can be represented as:
legacy log4j calls >---+
|
SLF4J calls >---+---> SLF4J --> logback
|
legacy JCL calls >---+
Now, if you don't like logback and prefer JUL, you can do the following:
legacy log4j calls >---+
|
SLF4J calls >---+---> SLF4J --+-> JUL
| |
legacy JCL calls >---+ ^
|
JUL calls >-----------------+
If you would prefer to stick with log4j, you can:
SLF4J calls >---+---> SLF4J --+-> log4j
| |
legacy JCL calls >---+ ^
|
log4j calls >------------------------+
Note that in the above diagrams, there are no direct logback calls
because normally one goes through SLF4J to log with logback. It is
actually a little less convenient to log directly through logback
instead of (indirectly) with SLF4J. For example, logbacks
documentation always uses SLF4J. (There are no examples in logback
docs that use logback directly.)
In other words, SLF4J acts as a universal logging API bridging between
the various logging systems. Logback is designed to support SLF4J API
from the start.
I hope this answers your questions,
>Thanks,
>Michael
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Logback: The reliable, generic, fast and flexible logging framework for Java.
