JUL vs. Log4j

JUL (Java Util Logging) vs. Log4j

Similarities

• Log4j and JUL are almost conceptually identical.
  But JUL renamed some concepts : For example appenders are "handlers," layouts are "formatters," and LoggingEvents are "LogRecords"
• JUL uses log levels the same way that Log4J uses levels.
  Although JUL has 9 default levels instead of 7
• JUL organizes loggers in a hierarchy and JUL loggers inherit properties from their parent loggers.
  Same way Log4j organizes its loggers.

Differences

• JUL uses API java.util.logging
• Log4j uses API org.apache.commons.logging
  

• JUL has Unclear log levels :
  SEVERE - WARNING - INFO - CONFIG - FINE - FINER - FINEST 
• Log4j has Clear log level using different names :
  FATAL - ERROR - WARN - INFO - DEBUG - TRACE
  

• No ERROR level in JUL
• There is an ERROR level in Log4j
  

• To log an exception in JUL, it is unclear what Level to use and why do I need to pass e.getMessage() parameter, Like :
  logger.log(Level.SEVERE, e.getMessage(), e);
• Simpler logging syntax in Log4j, Like
  logger.error(e);
  

• In JUL, there is no way to put a configuration in the classpath to be automatically picked up by the logging framework.
  To configure either modify the logging.properties in your JRE/lib folder
  OR 
  Set JVM parameter -Djava.util.logging.config.file=/my/folder/logging.properties
• In Log4j, there is a possibility to put an already configured configuration file.
  

• Another method to create a logger is missing in JUL, Like : 
  Logger.getLogger(class)
  
  Method to create logger is :
  private static Logger logger =
            Logger.getLogger(MyCLass.class.getName());
  
• Log4j has method to create a logger with syntax : 
  private Logger logger = Logger.getLogger(getClass());

What is JUL (Java Util Logging) ?

Java Util Log­ging (JUL) is Java 's own log­ging frame­work to make log­ging more con­fig­urable then the pre­vi­ous usage of System.out.println(), System.err.println() and e.printStackTrace() usage.

JUL is provided by Java package java.util.logging (introduced in 2002 with Java 1.4)

Java Util Log­ging is not very devel­oper friendly.

It con­tains just a very basic way of log­ging, a method called log where you always have to indi­cate the level.

And those lev­els are not very clear for usage :

• SEVERE
• WARNING
• INFO
• CONFIG
• FINE
• FINER
• FINEST

How to schedule jobs using XML in Quartz ?

Create “quartz.properties” and “quartz-config.xml” and ensure they are located at project classpath.

1. Create 3 Quartz’s jobs

public class Job1 implements Job {

   @Override

   public void execute(JobExecutionContext context) throws JobExecutionException {

      System.out.println("Job 1 is runing");

   }

}

public class Job2 implements Job {

   @Override

   public void execute(JobExecutionContext context) throws JobExecutionException {

      System.out.println("Job 2 is runing");

   }

}

2. Create quartz.properties

org.quartz.scheduler.instanceName = MyScheduler

org.quartz.threadPool.threadCount = 3

org.quartz.jobStore.class = org.quartz.simpl.RAMJobStore

org.quartz.plugin.jobInitializer.class =org.quartz.plugins.xml.XMLSchedulingDataProcessorPlugin

org.quartz.plugin.jobInitializer.fileNames = quartz-config.xml

org.quartz.plugin.jobInitializer.failOnFileNotFound = true

3. Create quartz-config.xml

<?xml version="1.0" encoding="UTF-8"?>

<job-scheduling-data

  xmlns="http://www.quartz-scheduler.org/xml/JobSchedulingData"

  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

  xsi:schemaLocation="http://www.quartz-scheduler.org/xml/JobSchedulingData

  http://www.quartz-scheduler.org/xml/job_scheduling_data_1_8.xsd"   version="1.8">

  <schedule>

    <job>

      <name>Job1</name>

      <group>myGroupy</group>

      <description>This is Job 1</description>

      <job-class>com.shaan.Job1</job-class>

    </job>

    <trigger>

      <cron>

        <name>myTriggerName1</name>

        <job-name>Job1</job-name>

        <job-group>myGroup</job-group>

        <!-- It will run every 5 seconds -->

        <cron-expression>0/5 * * * * ?</cron-expression>

      </cron>

    </trigger>

  </schedule>

  <schedule>

    <job>

      <name>Job2</name>

      <group>myGroup</group>

      <description>This is Job 2</description>

      <job-class>com.shaan.Job2</job-class>

    </job>

    <trigger>

      <cron>

        <name>myTriggerName2</name>

        <job-name>Job2</job-name>

        <job-group>myGroup</job-group>

        <!-- It will run every 5 seconds -->

        <cron-expression>0/5 * * * * ?</cron-expression>

      </cron>

    </trigger>

  </schedule>

</job-scheduling-data>

4. Entry in web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app ...>

  <listener>

    <listener-class> 

      org.quartz.ee.servlet.QuartzInitializerListener 

    </listener-class>

  </listener>

</web-app>

How to run multiple jobs in Quartz ?

In Quartz scheduler framework, each job will be attached to an unique trigger and run it by scheduler.

1. Create 3 Quartz’s jobs

public class Job1 implements Job { 

   @Override

   public void execute(JobExecutionContext context) throws JobExecutionException {

      System.out.println("Job 1 is runing");

   }

}

public class Job2 implements Job {

   @Override

   public void execute(JobExecutionContext context) throws JobExecutionException {

      System.out.println("Job 2 is runing");

   }

}

public class Job3 implements Job {

   @Override

   public void execute(JobExecutionContext context) throws JobExecutionException {

      System.out.println("Job 3 is runing");

   } 

}

2. Declare above 3 jobs, assign to 3 particular triggers and schedule it

JobKey jobKey1 = new JobKey("job1", "group1");

JobDetail job1 = JobBuilder.newJob(Job1.class).withIdentity(jobKey1).build();

JobKey jobKey2 = new JobKey("job2", "group1");

JobDetail job2 = JobBuilder.newJob(Job2.class).withIdentity(jobKey2).build();

JobKey jobKey3 = new JobKey("job3", "group1");

JobDetail job3 = JobBuilder.newJob(Job3.class).withIdentity(jobKey3).build();

Trigger trigger1 = TriggerBuilder.newTrigger().withIdentity("myTriggerName1", "group1")

    .withSchedule(CronScheduleBuilder.cronSchedule("0/5 * * * * ?")).build();

Trigger trigger2 = TriggerBuilder.newTrigger().withIdentity("myTriggerName2", "group1")

    .withSchedule(CronScheduleBuilder.cronSchedule("0/5 * * * * ?")).build();

Trigger trigger3 = TriggerBuilder.newTrigger().withIdentity("myTriggerName3", "group1")

    .withSchedule(CronScheduleBuilder.cronSchedule("0/5 * * * * ?")).build();

Scheduler scheduler = new StdSchedulerFactory().getScheduler();

scheduler.start();

scheduler.scheduleJob(job1, trigger1);

scheduler.scheduleJob(job2, trigger2);

scheduler.scheduleJob(job3, trigger3);