Logging » History » Revision 3
Revision 2 (Igor Melnichenko, 05/20/2014 05:31 PM) → Revision 3/6 (Igor Melnichenko, 05/20/2014 05:43 PM)
h1. Logging
Currently, Retrascope logging subsystem is based on the JUL framework (java.util.logging).
h2. Format of entries
"date. level: message"
Date format: "yyyy.MM.dd HH:mm:ss.SSS". This field along with level field are automatically filled in by the log formatter, while the message field is constructed by logging object.
Message format: "header: message". Typically, header is a logging object class or instance name.
h2. Usage
The root logger is configured in the ru.ispras.retrascope.Retrascope class as logger with name ru.ispras.retrascope. All loggers of other Retrascope classes must be created with a name of the format "<class_package>.<class/instance_name>" (ru.ispras.retrascope.engine.efsm.simulator.EfsmSimulator, for example). Because of that all such loggers will use the root logger as parent and send their messages to root handlers, so generally there is no need to configure non-root handlers.
Logging must be used in all Engine classes.
h3. Examples
The usage examples from the EfsmSimulator and Retrascope classes are presented below.
h4. Logger creation
this.logger = Logger.getLogger(this.getClass().getCanonicalName());
h4. Logging message without throwable object
if (this.logger.isLoggable(Level.INFO)) {
this.logger.log(Level.INFO, EfsmSimulator.LOG_ENTRY_HEADER EfsmSimulator.LOG_HEADER
+ ": starting to process the events: " + events);
}
h4. Logging message with throwable object
catch (IOException | SecurityException e) {
if (Retrascope.logger.isLoggable(Level.SEVERE)) {
Retrascope.logger.log(Level.SEVERE, Retrascope.LOG_ENTRY_HEADER Retrascope.LOG_HEADER +
": the exception has been encountered during a logging file handler configuring: ", e);
}
}