The Unisys Eclipse logging plug-in provides a convenience wrapper around the Apache Log4J package (http://logging.apache.org/) for use in plug-ins hosted by Eclipse software. To use the logging plug-in, you instantiate a Logger object in your plug-in and embed logging method calls in required locations throughout your code.
The plug-in provides three predefined appenders, or log interface modules:
Rotating file appender, which writes log messages to a text file. When the file reaches a preconfigured size, the plug-in closes the file and starts a new log file. When the number of files reaches a preconfigured number, the oldest file is overwritten.
Windows NT Event Log appender, which writes messages to the Windows Event Log.
Eclipse Log appender, which writes selected log messages into the Eclipse Error Log.
The logging plug-in defines five severity levels for log messages, listed below from least to most severe:
DEBUG
INFO
WARN
ERROR
FATAL
To configure the severity level for log messages refer to Setting the Log File.
Configuring the severity at a specific level causes messages at that level and all higher (more severe) levels to be directed to it. For example, a severity at the ERROR level causes all messages at the ERROR and FATAL levels to go to it; a severity at the DEBUG level receives all messages.
If you make logging method calls at levels for which no severity level is enabled, that call has no effect. For example, logging calls at the DEBUG level could be sprinkled liberally throughout your code for use while doing development or debugging, but simply disabled for production use. The logging level selection is very efficient, so calls to disabled logging levels have little performance impact.