ejb-timer: Example of EJB Timer Service

The ejb-timer quickstart demonstrates how to use the EJB timer service @Schedule and @Timeout annotations with WildFly.

What is it?

The ejb-timer quickstart demonstrates how to use the EJB timer service in WildFly Application Server. This example creates a timer service that uses the @Schedule and @Timeout annotations.

The following EJB Timer services are demonstrated:

@Schedule: Uses this annotation to mark a method to be executed according to the calendar schedule specified in the attributes of the annotation. This example schedules a message to be printed to the server console every 6 seconds.
@Timeout: Uses this annotation to mark a method to execute when a programmatic timer goes off. This example sets the timer to go off every 3 seconds, at which point the method prints a message to the server console.

System Requirements

The application this project produces is designed to be run on WildFly Application Server 13 or later.

All you need to build this project is Java 8.0 (Java SDK 1.8) or later and Maven 3.3.1 or later. See Configure Maven to Build and Deploy the Quickstarts to make sure you are configured correctly for testing the quickstarts.

Use of WILDFLY_HOME

In the following instructions, replace WILDFLY_HOME with the actual path to your WildFly installation. The installation path is described in detail here: Use of WILDFLY_HOME and JBOSS_HOME Variables.

Start the WildFly Standalone Server

Open a terminal and navigate to the root of the WildFly directory.
Start the WildFly server with the default profile by typing the following command.
```
$ WILDFLY_HOME/bin/standalone.sh 
```
Note
For Windows, use the WILDFLY_HOME\bin\standalone.bat script.

Build and Deploy the Quickstart

Make sure you start the WildFly server as described above.
Open a terminal and navigate to the root directory of this quickstart.
Type the following command to build the artifacts.
```
$ mvn clean package wildfly:deploy
```

This deploys the ejb-timer/target/ejb-timer.war to the running instance of the server.

You should see a message in the server log indicating that the archive deployed successfully.

Access the Application

This application only prints messages to stdout. To see it working, check the server log. You should see similar output:

INFO  [stdout] (EJB default - 10) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:12 EST
INFO  [stdout] (EJB default - 2) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:12 EST
INFO  [stdout] (EJB default - 4) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:15 EST
INFO  [stdout] (EJB default - 3) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:18 EST
INFO  [stdout] (EJB default - 5) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:18 EST
INFO  [stdout] (EJB default -7) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:21 EST
INFO  [stdout] (EJB default - 9) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:24 EST
INFO  [stdout] (EJB default - 6) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:24 EST
INFO  [stdout] (EJB default - 8) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:27 EST
INFO  [stdout] (EJB default - 1) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:30 EST
INFO  [stdout] (EJB default - 10) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:30 EST
INFO  [stdout] (EJB default - 2) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:33 EST
INFO  [stdout] (EJB default - 4) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:36 EST
INFO  [stdout] (EJB default - 3) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:36 EST
INFO  [stdout] (EJB default - 5) TimeoutExample.scheduler() EJB timer service timeout at 2014.11.25 AD at 11:57:39 EST
INFO  [stdout] (EJB default - 7) ScheduleExample.doWork() invoked at 2014.11.25 AD at 11:57:42 EST

Existing threads in the thread pool handle the invocations. They are rotated and the name of the thread that handles the invocation is printed within the parenthesis (EJB Default - #).

Undeploy the Quickstart

When you are finished testing the quickstart, follow these steps to undeploy the archive.

Make sure you start the WildFly server as described above.
Open a terminal and navigate to the root directory of this quickstart.
Type this command to undeploy the archive:
```
$ mvn wildfly:undeploy
```

Run the Quickstart in Red Hat JBoss Developer Studio or Eclipse

You can also start the server and deploy the quickstarts or run the Arquillian tests in Red Hat JBoss Developer Studio or from Eclipse using JBoss tools. For general information about how to import a quickstart, add a WildFly server, and build and deploy a quickstart, see Use JBoss Developer Studio or Eclipse to Run the Quickstarts.

Debug the Application

If you want to debug the source code of any library in the project, run the following command to pull the source into your local repository. The IDE should then detect it.

$ mvn dependency:sources

ejb-timer: Example of EJB Timer Service - @Schedule and @Timeout