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JavaOnTracks: Logging

Why not use log4j ?

Well to be honest i don't have any good arguments besides that i didn't want to have any dependencies, and the fact that i never real liked log4j. Why don't i like it, not sure to be honest.

Anyway you are free to use log4j together with JavaOnTracks of course, otherwise you can use JavaOnTracks built-in logger.

JavaOnTracks logger

This is a simple implementation of a logging system.
It is thread safe, and logs all to a single file (rotated at each restart)

What it has going for it, are a bunch of methods making it easy to log messages, which are nicely formatted in a single log file and the fact it's very lightweight.

It support log Categories, so you can differentiate where the log come from, as well as log levels.
Also it has methods which allow automatic logging of class/servlet name in the log file, as well as userName/ IP address etc...

It is recommended to only enable log levels 3 and up (INFO +) unless debugging an issue.
Please note that when lat the trace and debug levels, a lot of potentially sensitive data might get logged such as when tracing DB queries, password might be logged etc...

See

JOTLogger javadoc for more infos.

Example

logger init

// note "null" means to log all categories.
JOTLogger.init("/tmp/log.txt", JOTLogger.ALL_LEVELS, null);

example logging entries

// write a log message which will contain the current object class name and the message
    JOTLogger.warning(this, "huho something ain't right");
// same for a static class
    JOTLogger.warning(JOTApplicationTest.class, "huho something ain't right");

// now we also specify a category
    JOTLogger.debug(cat, this, "huho something ain't right");

// now we also specify a category and a user login name
    JOTLogger.debug(cat, this, user.getLogin(), "huho something ain't right")

// log an exception (with the trace) at the default "error" level
    JOTLogger.logException(this, "it's broke!", yourException)
// same but with a custom level
    JOTLogger.logException(JOTLogger.TRACE_LEVEL,this, "it's broke!", yourThrowable)

See

JOTLogger javadoc, for the whole list of logging methods.

Example log file output

# See format: Category / log level / timestamp / location:class /(user)/ message
....
JOT.DB 0 5_6_2008_9_52_23-983 net.jot.persistance.JOTModelMapping  Retrieving impl : net.jot.persistance.query.JOTDBQueryImpl
JOT.DB 1 5_6_2008_9_52_23-983 net.jot.db.JOTDBManager  Trying to connect to database: default
JOT.DB 1 5_6_2008_9_52_23-983 net.jot.db.JOTDBPool  default: Retrieving a connection
JOT.DB 1 5_6_2008_9_52_23-983 net.jot.db.JOTDBManager  Got Connection default/0
JOT.DB 1 5_6_2008_9_52_23-984 net.jot.db.JOTDBManager  Executing query: SELECT * FROM "league" WHERE "dataid"  = ? LIMIT 1
JOT.DB 0 5_6_2008_9_52_23-984 net.jot.db.JOTDBManager  With Parameters: 7,
JOT.DB 1 5_6_2008_9_52_23-985 net.jot.db.JOTDBPool  default: Freing connection: 0
JOT.DB 1 5_6_2008_9_52_23-985 net.jot.db.JOTDBManager  Released Connection default/0
JOT.DB 1 5_6_2008_9_52_23-990 JOTDBModel  *** loadFromRS() ***
JOT.DB 1 5_6_2008_9_52_23-990 JOTDBModel  Columns list from DB metadata: [dataid, dataname, dataowner, datacountry, datacity, datashortcut, datasearchname, datastate, datatimezone]
JOT.FLOW 1 5_6_2008_9_52_23-990 net.jot.web.ctrl.JOTMasterController  End Processing View: net.colar.hockey.view.user.LeagueIndexView
JOT.FLOW 1 5_6_2008_9_52_23-991 net.jot.web.view.JOTViewParser (bDoe) Caching template: /home/blah/build/web/teamtpl.html
JOT.FLOW 0 5_6_2008_9_52_23-994 net.jot.web.view.JOTViewParser  (bDoe) Removing all <jot:remove> tags content.
JOT.FLOW 0 5_6_2008_9_52_23-995 net.jot.web.view.JOTViewParser  (bDoe) Include:innerPage
....
## EXCEPTION abstract example

APP 4 4_14_2008_14_19_20-575 java.lang.Class  Error parsing template !
APP 4 4_14_2008_14_19_20-576 trace  java.lang.NullPointerException
APP 4 4_14_2008_14_19_20-576 trace      at net.jot.web.widget.JOTWidgetBaseProperties.getPropertyDefaultValue(JOTWidgetBaseProperties.java:74)
APP 4 4_14_2008_14_19_20-576 trace      at net.jot.web.widget.JOTWidgetBaseProperties.getRefreshEvery(JOTWidgetBaseProperties.java:100)
APP 4 4_14_2008_14_19_20-576 trace      at net.jot.web.widget.JOTWidgetBase.render(JOTWidgetBase.java:64)
APP 4 4_14_2008_14_19_20-576 trace      at net.jot.web.view.JOTViewParser.doWidgets(JOTViewParser.java:1175)
.....

Last modified: Wed Dec 10 19:09:29 EST 2008 by Thibaut Colar

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