MicroLog

Darius KatzJohan Karlsson

Background

Johan K. noticed the lack of a good logger for the Java ME environment. So he simply sat down and coded the first version of MicroLog and put it on SourceForge. The rest is history...

Features overview

Log4j wannabeLog to the consoleLog to RMS (accessible with an included midlet)Log to fileLog to FormLog over Bluetooth (coming real soon)Log over GPRS (coming soon)Flexible formattingConfigurable

Using MicroLog

//Init the loggerLogger log = Logger.getLogger();log.configure(properties);......log.info(“Log this text”);

Using MicroLog

//Init the loggerLogger log = Logger.getLogger();log.configure(properties);......log.info(“Log this text”);

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Properties

Properties is a module in MicroLog which helps to set up the Logger. Example:

microlog.level=DEBUGmicrolog.appender=net.sf.microlog.appender.RecordStoreA...microlog.appender.RecordStoreAppender.maxLogEntries=20microlog.formatter=net.sf.microlog.format.SimpleFormatter

Line 2 in all its glory:microlog.appender=net.sf.microlog.appender.RecordStoreAppender;net.sf.microlog.appender.ConsoleAppendernote: two Appenders

Property sources

4 different sources today: Default values Property file Application properties (attributes) Numbered application properties (attributes)

Default values

Class is called DefaultValuesHardcoded in the class. Used if not changed by user in another property source.All “system properties” should be included. (In our case everything that MicroLog uses.)

Property file

Class is called PropertyFileA file named microlog.properties in the midlet-root contains the properties/values.User can change the default values.User can add own values.

Example:microlog.level=DEBUGmicrolog.appender=net.sf.microlog.appender.RecordStoreA...microlog.appender.RecordStoreAppender.maxLogEntries=20microlog.formatter=net.sf.microlog.format.SimpleFormatter

Application properties

Class is called AppPropertyProperties are added in the jad-file or in the manifest-file as usual attributes (property:value) User can change the default values.User can override the values in the properties file.User can not add own values.

Numbered application props

Class is called NumberedAppPropertyProperties are added in the jad-file or in the manifest-file as attributes in a special way: AppProperty_1 : MyProperty=MyValue AppProperty_2 : MyOtherProperty=MyOtherValue AppProperty_3 : SomeOtherProperty=SomeOtherValue

User can change the default values.User can override the values in the properties file and the values set in application properties.User can add own values.

Repetition

Values are read in the following order:1.DefaultValues2.PropertyFile3.AppProperty4.NumberedAppProperty

Each new level overrides the same properties in the previous levels.

Using Properties

//Create a new properties in the MIDlet classProperties properties = new Properties(this);...

...myString = (String)properties.get(“MyProperty”);myString = properties.getString(“MyProperty”);...

this is the midlet

Finally

Use Properties in your own mobile applications

Using MicroLog

//Init the loggerLogger log = Logger.getLogger();log.configure(properties);......log.info(“Log this text”);

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Using MicroLog, the final cut

//Init propertiesProperties properties = new Properties(this);

//Init the loggerLogger log = Logger.getLogger();log.configure(properties);......log.info(“Log this text”);log.error(“Log this error”);

MicroLog building blocks

Appenders (“output channels”) ConsoleAppender (to the console) FileAppender (to a file via JSR75, FileConnection API) RecordStoreAppender (to the RMS) FormAppender (to a form) BluetoothAppender (under development) GPRSAppender (to be developed) more...

Formatters (“looks of the output”) SimpleFormatter (predefined, simple) ConfigurableFormatter (under development) more?

Popular Appenders

ConsoleAppender Used in emulators Used in P900/P910 with a utility

RecordStoreAppender Used in all mobiles Comes with a MIDlet that views the logs

BluetoothAppender Send logs to the PC Used with mobiles that support Bluetooth

How to add to your projectDownload and unpackCopy source-code to your project (JAR-file in the future when the API is finalized) copy microlog.properties if needed

Set properties in application properties OR in microlog.properties file (important: correct CRLF)

Add MIDlet to suite RecordStoreLogViewer (if needed)

Add init code in MIDlet constructor OR in MIDlet startUp() method

Use don't abuse (might slow down)

Demo

Live on stage

How to add to your projectDownload and unpackCopy source-code to your project (JAR-file in the future when the API is finalized) copy microlog.properties if needed

Set properties in application properties OR in microlog.properties file (important: correct CRLF)

Add MIDlet to suite RecordStoreLogViewer (if needed)

Add init code in MIDlet constructor OR in MIDlet startUp() method

Use don't abuse (might slow down)

Code help wanted

BluetoothAppender (BT-expert needed)GprsAppenderMore flexible Formatter perhaps “%d %t %m” etc.

Get hold of stacktrace in exceptionImprove read of microlog.properties fileAnything else you'd likeNon-coding things: Design homepage Tutorials FAQ Manuals

Links

MicroLog homepage:http://microlog.sourceforge.net

Project page on SourceForge:http://sf.net/projects/microlog

Thank you for listening