Project

General

Profile

Logging » History » Version 4

Igor Melnichenko, 05/20/2014 05:44 PM

1 1 Igor Melnichenko
h1. Logging
2
3
Currently, Retrascope logging subsystem is based on the JUL framework (java.util.logging).
4
5
h2. Format of entries
6
7
"date. level: message"
8
9
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.
10
Message format: "header: message". Typically, header is a logging object class or instance name.
11
12
h2. Usage
13
14
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.
15 2 Igor Melnichenko
Logging must be used in all Engine classes.
16 1 Igor Melnichenko
17
h3. Examples
18
19
The usage examples from the EfsmSimulator and Retrascope classes are presented below.
20
21
h4. Logger creation
22
23
this.logger = Logger.getLogger(this.getClass().getCanonicalName());
24
25
h4. Logging message without throwable object
26
27
if (this.logger.isLoggable(Level.INFO)) {
28 4 Igor Melnichenko
  this.logger.log(Level.INFO, this.logEntryHeader
29 1 Igor Melnichenko
      + ": starting to process the events: " + events);
30
}
31
32
h4. Logging message with throwable object
33
34
catch (IOException | SecurityException e) {
35
  if (Retrascope.logger.isLoggable(Level.SEVERE)) {
36 3 Igor Melnichenko
    Retrascope.logger.log(Level.SEVERE, Retrascope.LOG_ENTRY_HEADER +
37 1 Igor Melnichenko
        ": the exception has been encountered during a logging file handler configuring: ", e);
38
  }
39
}