[logback-user] Using Logback on JDK1.4 possible?

Ceki Gülcü listid at qos.ch
Tue Jan 2 10:07:07 CET 2007

Hello Fouche,

Thank you for using logback.

Logback uses several linguistic features introduced in JDK 1.5. Hence the 
JDK 1.5 dependency.


At 09:58 AM 1/2/2007, f_du_preez at limehouse.co.za wrote:
>Does anybody know if it is it possible to use Logback on JDK1.4? I get an
>UnsupportedClassVersionError when trying to instantiate a Logback logger
>through SLF4J.
>I've had a look at pom.xml and see that the jdkLevel is set to 1.5. So the
>exception makes sense - I'm trying to run 1.5 code against a 1.4 jdk... That
>said I find it strange the Logback only supports jdk1.5 and higher. Anybody
>running it against a 1.4 jdk? If so, how did you manage to do it?
>To be complete:
>The code that I'm using is very simple:
>  Logger log = LoggerFactory.getLogger(InitLog.class);
>  log.debug(">>> Logging Initialized");
>The exception I'm getting:
>java.lang.UnsupportedClassVersionError: org/slf4j/LoggerFactory (Unsupported
>major.minor version 49.0)
>         at java.lang.ClassLoader.defineClass0(Native Method)
>         at java.lang.ClassLoader.defineClass(ClassLoader.java(Compiled Code))
>         at 
> java.security.SecureClassLoader.defineClass(SecureClassLoader.java(Compiled
>         at
>         at
>         at
>         at java.lang.ClassLoader.loadClass(ClassLoader.java(Compiled Code))
>         at za.ibm.slftest.servlet.InitLog.init(InitLog.java:15)
>Fouche du Preez

Ceki Gülcü
Logback: The reliable, generic, fast and flexible logging framework for Java.

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