How to add custom log handler to Google App Engine?

Question

I am trying to add a custom log handler to my java application. I have implemented a InnerLogger class that extends java.util.Logging.Handler class. And in my logging.properties declared as a handler:

handlers:com.mycompany.util.InnerLogger

But when I launch the development sever, I got the following error:

Can't load log handler "com.mycompany.util.InnerLogger"
java.lang.ClassNotFoundException: com.mycompany.util.InnerLogger

I can add my custom handler to loggers one by one ,but I just wondering is there a way to add it to all loggers.

Thanks

Answer 1

I was able to add a Handler to the root Logger when my application initializes. You can put this code in a warmup task or servlet filter.

private static Logger LOG;

...

LOG = Logger.getLogger("");
LOG.addHandler(myCustomHandler);

Its not as graceful as using logging.properties, but it is an adequate workaround when running on GAE.

Answer 2

It might not the solution you were looking for, but have you considered using Simple Logging Facade for Java (SLF4J) in your application instead of using directly JUL?