Injectable ServerLog instance

[GoogleCodeExporter]

We have an old legacy logging infrastructure where I work. We've got an slf4j 
facade that pipes slf4j messages into our framework, but even if Issue 18 gets 
solved, that would still mean two translations of logging levels (gwt-log to 
slf4j to LegacyLog). Could you make the instance of ServerLog that Log uses 
injectable? The following code is pulled from java.util.logging.LogManager's 
static init code:

String cname = System.getProperty("gwt-log.ServerLogImpl");
if (cname != null) {
    try {
        Class clazz = ClassLoader.getSystemClassLoader().loadClass(cname);
        impl = (ServerLog) clz.newInstance();
    } catch (ClassNotFoundException ex) {
        try {
            Class clz = Thread.currentThread()
                .getContextClassLoader().loadClass(cname);
            impl = (ServerLog) clz.newInstance();
        } catch (ClassNotFoundException ex) {
            throw new UnsupportedOperationException("Invalid class name");
        }
    }
}

Original issue reported on code.google.com by *stephen...@nanometrics.ca on 25 Nov 2010 at 10:39

[GoogleCodeExporter]

An alternate (and possibly simpler option) would be to take after slf4j, and 
just have a static class binder. At the start of your static init block, have 
this:

try {
    impl = new com.allen_sauer.gwt.log.server.impl.CustomServerLogImpl();
} catch (NoClassDefFoundError e) {
    // Do nothing
}

That way, if people want to have a custom logger, they just include it in their 
own jar. If not, it will continue on as normal. This avoids the race condition 
of trying to set the system propery in code before Log's init code is run (if 
you're not able to control system properties externally).

Original comment by *stephen...@nanometrics.ca on 25 Nov 2010 at 11:25

[GoogleCodeExporter]

Original comment by fredsa on 30 Apr 2012 at 11:27

• Changed state: GitPatchesWelcome

[GoogleCodeExporter]

Just a setter would be cool, i have the same problem within a tomcat instance.

We solve it right now with a DIRTY HACK:

Class<Log> c = Log.class;
try {
    Field impl = c.getDeclaredField("impl"); //$NON-NLS-1$
    impl.setAccessible(true);
    impl.set(null, new RemoteLoggingLog());
    impl.setAccessible(false);
} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | 
IllegalAccessException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Original comment by mse...@gmail.com on 30 Apr 2013 at 12:40