LOG4 Log Classification level

off

Off levels are the highest level and are used to turn off all log records. FATAL fatal mistake.

FATAL level indicates that each serious error event will cause the application to exit. Error Errors

The error level indicates that, while an incorrect event occurs, it does not affect the continued operation of the system. WARN Warning

The WARN level indicates a scenario where a potential error occurs. Info Info

The INFO level indicates that the message highlights the application's running process at the coarse-grained levels. Debug Debug

The debug level indicates that fine-grained informational events are useful for debugging applications. TRACE

Record event messages in a more granular format than Debug. All

All levels are the lowest level and are used to open all log records. from high to low

Off, FATAL, ERROR, WARN, INFO, DEBUG, TRACE, all

Field Summary
Static level	All The all has the lowest possible rank and are intended to turn on all logging.
Static level	DEBUG The DEBUG level designates fine-grained informational events, are most useful to debug a application.
Static level	ERROR The error level designates error events this might still allow the application to continue running.
Static level	FATAL The FATAL level designates very severe error events that would presumably lead the application to abort.
Static Lrevel	INFO The INFO level designates informational messages that highlight the progress to the application level.
Static level	off The off has the highest possible rank and are intended to turn off logging.
Static level	TRACE The TRACE level designates finer-grained informational events than the DEBUG
static int	Trace_int TRACE level integer value.
Static level	WARN The WARN level designates potentially harmful situations.

Website address: log4j API http://jakarta.apache.org/log4j/docs/api/index.html