Differences between Log and Logger?

Question

I have seen people use this way:

Logger logger = Logger.getLogger("com.foo");

and I have seen the other way:

Log log = LogFactory.getLog(CLASS.class);

What's the differences behind them? Thanks.

Answer 1

The call to Logger.getLogger is from the log4j api.

Logger logger = Logger.getLogger("com.foo");

Documentation

---

The call to LogFactory.getLog() is from the commons-logging api.

Log log = LogFactory.getLog(CLASS.class);

Documentation

log4j is a logging framework, i.e. it provides the code to log messages. Commons-logging is an abstraction layer for logging frameworks, it doesn't log anything itself.