Setup slf4j to maven project

The Simple Logging Facade for Java (SLF4J) serves as a simple facade or abstraction for various logging frameworks

 

Add dependency to your Maven POM

you need “slf4j-api.jar” and your preferred binding, like log4j “slf4j-log4j12.jar“. Just declares the dependency in your pom.xml.

        
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>${slf4jVersion}</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.16</version>
            <scope>runtime</scope>
        </dependency>
    

 

log4.properties

the properties code put in java/resources

        # Direct log messages to a log file
        log4j.appender.file=org.apache.log4j.RollingFileAppender
        log4j.appender.file.File=C:\\myapp.log
        log4j.appender.file.MaxFileSize=1MB
        log4j.appender.file.MaxBackupIndex=1
        log4j.appender.file.layout=org.apache.log4j.PatternLayout
        log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

        # Direct log messages to stdout
        log4j.appender.stdout=org.apache.log4j.ConsoleAppender
        log4j.appender.stdout.Target=System.out
        log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
        log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

        # Root logger option
        log4j.rootLogger=INFO, file, stdout

        # Log everything. Good for troubleshooting
        log4j.logger.org.hibernate=INFO

        # Log all JDBC parameters
        log4j.logger.org.hibernate.type=ALL
    

 

Put logging code in your classes

the imports section

        import org.slf4j.Logger;
        import org.slf4j.LoggerFactory;
    

Add the following at the top of your class in the global section

        static final Logger LOG = LoggerFactory.getLogger(MyClassName.class);
    

The following code how to use SLF4j in an application, as you can see the fatal logging level has not been implemented.

        public static void main(String[] args) {

            Logger logger = LoggerFactory.getLogger(Slf4jHelloWorld.class);

            logger.trace("Hello World");
            logger.debug("Hello World");
            logger.info("Hello World");
            logger.warn("Hello World");
            logger.error("Hello World");
        }