Modern applications often need to run specific tasks periodically. In this guide, you learn how to schedule periodic clustered tasks using the Quartz extension.

If you only need to run in-memory scheduler use the Scheduler extension.

Prerequisites

To complete this guide, you need:

  • Roughly 15 minutes

  • An IDE

  • JDK 17+ installed with JAVA_HOME configured appropriately

  • Apache Maven ${proposed-maven-version}

  • Docker and Docker Compose or Podman, and Docker Compose

  • Optionally the Quarkus CLI if you want to use it

  • Optionally Mandrel or GraalVM installed and configured appropriately if you want to build a native executable (or Docker if you use a native container build)

Architecture

In this guide, we are going to expose one Rest API tasks to visualise the list of tasks created by a Quartz job running every 10 seconds.

Solution

We recommend that you follow the instructions in the next sections and create the application step by step. However, you can go right to the completed example.

Clone the Git repository: git clone $${quickstarts-base-url}.git, or download an $${quickstarts-base-url}/archive/main.zip[archive].

The solution is located in the quartz-quickstart directory.

Creating the Maven project

First, we need a new project. Create a new project with the following command:

CLI
quarkus create app org.acme:quartz-quickstart \
    --extension='rest-jackson,quartz,hibernate-orm-panache,flyway,jdbc-postgresql' \
    --no-code
cd quartz-quickstart

To create a Gradle project, add the --gradle or --gradle-kotlin-dsl option.

For more information about how to install and use the Quarkus CLI, see the Quarkus CLI guide.

Maven
mvn io.quarkus.platform:quarkus-maven-plugin:${project.version}:create \
    -DprojectGroupId=org.acme \
    -DprojectArtifactId=quartz-quickstart \
    -Dextensions='rest-jackson,quartz,hibernate-orm-panache,flyway,jdbc-postgresql' \
    -DnoCode
cd quartz-quickstart

To create a Gradle project, add the -DbuildTool=gradle or -DbuildTool=gradle-kotlin-dsl option.

For Windows users:

  • If using cmd, (don’t use backward slash \ and put everything on the same line)

  • If using Powershell, wrap -D parameters in double quotes e.g. "-DprojectArtifactId=quartz-quickstart"

It generates:

  • the Maven structure

  • a landing page accessible on http://localhost:8080

  • example Dockerfile files for both native and jvm modes

  • the application configuration file

The Maven project also imports the Quarkus Quartz extension.

If you already have your Quarkus project configured, you can add the quartz extension to your project by running the following command in your project base directory:

CLI
quarkus extension add quartz
Maven
./mvnw quarkus:add-extension -Dextensions='quartz'
Gradle
./gradlew addExtension --extensions='quartz'

This will add the following to your build file:

pom.xml
<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-quartz</artifactId>
</dependency>
build.gradle
implementation("io.quarkus:quarkus-quartz")

To use a JDBC store, the quarkus-agroal extension, which provides the datasource support, is also required.

Creating the Task Entity

In the org.acme.quartz package, create the Task class, with the following content:

package org.acme.quartz;

import jakarta.persistence.Entity;
import java.time.Instant;
import jakarta.persistence.Table;

import io.quarkus.hibernate.orm.panache.PanacheEntity;

@Entity
@Table(name="TASKS")
public class Task extends PanacheEntity { (1)
    public Instant createdAt;

    public Task() {
        createdAt = Instant.now();
    }

    public Task(Instant time) {
        this.createdAt = time;
    }
}
1 Declare the entity using Panache

Creating a scheduled job

In the org.acme.quartz package, create the TaskBean class, with the following content:

package org.acme.quartz;

import jakarta.enterprise.context.ApplicationScoped;

import jakarta.transaction.Transactional;

import io.quarkus.scheduler.Scheduled;

@ApplicationScoped (1)
public class TaskBean {

    @Transactional
    @Scheduled(every = "10s", identity = "task-job") (2)
    void schedule() {
        Task task = new Task(); (3)
        task.persist(); (4)
    }
}
1 Declare the bean in the application scope
2 Use the @Scheduled annotation to instruct Quarkus to run this method every 10 seconds and set the unique identifier for this job.
3 Create a new Task with the current start time.
4 Persist the task in database using Panache.

Scheduling Jobs Programmatically

An injected io.quarkus.scheduler.Scheduler can be used to schedule a job programmatically. However, it is also possible to leverage the Quartz API directly. You can inject the underlying org.quartz.Scheduler in any bean:

package org.acme.quartz;

@ApplicationScoped
public class TaskBean {

    @Inject
    org.quartz.Scheduler quartz; (1)

    void onStart(@Observes StartupEvent event) throws SchedulerException {
       JobDetail job = JobBuilder.newJob(MyJob.class)
                         .withIdentity("myJob", "myGroup")
                         .build();
       Trigger trigger = TriggerBuilder.newTrigger()
                            .withIdentity("myTrigger", "myGroup")
                            .startNow()
                            .withSchedule(
                               SimpleScheduleBuilder.simpleSchedule()
                                  .withIntervalInSeconds(10)
                                  .repeatForever())
                            .build();
       quartz.scheduleJob(job, trigger); (2)
    }

    @Transactional
    void performTask() {
        Task task = new Task();
        task.persist();
    }

    // A new instance of MyJob is created by Quartz for every job execution
    public static class MyJob implements Job {

       @Inject
       TaskBean taskBean;

       public void execute(JobExecutionContext context) throws JobExecutionException {
          taskBean.performTask(); (3)
       }

    }
}
1 Inject the underlying org.quartz.Scheduler instance.
2 Schedule a new job using the Quartz API.
3 Invoke the TaskBean#performTask() method from the job. Jobs are also container-managed beans if they belong to a bean archive.
By default, the scheduler is not started unless a @Scheduled business method is found. You may need to force the start of the scheduler for "pure" programmatic scheduling. See also Quartz Configuration Reference.

Updating the application configuration file

Edit the application.properties file and add the below configuration:

# Quartz configuration
quarkus.quartz.clustered=true (1)
quarkus.quartz.store-type=jdbc-cmt (2)
quarkus.quartz.misfire-policy.task-job=ignore-misfire-policy (3)

# Datasource configuration.
quarkus.datasource.db-kind=postgresql
quarkus.datasource.username=quarkus_test
quarkus.datasource.password=quarkus_test
quarkus.datasource.jdbc.url=jdbc:postgresql://localhost/quarkus_test

# Hibernate configuration
quarkus.hibernate-orm.schema-management.strategy=none
quarkus.hibernate-orm.log.sql=true
quarkus.hibernate-orm.sql-load-script=no-file

# flyway configuration
quarkus.flyway.connect-retries=10
quarkus.flyway.table=flyway_quarkus_history
quarkus.flyway.migrate-at-start=true
quarkus.flyway.baseline-on-migrate=true
quarkus.flyway.baseline-version=1.0
quarkus.flyway.baseline-description=Quartz
1 Indicate that the scheduler will be run in clustered mode
2 Use the database store to persist job related information so that they can be shared between nodes
3 The misfire policy can be configured for each job. task-job is the identity of the job.

Valid misfire policy for cron jobs are: smart-policy, ignore-misfire-policy, fire-now and cron-trigger-do-nothing. Valid misfire policy for interval jobs are: smart-policy, ignore-misfire-policy, fire-now, simple-trigger-reschedule-now-with-existing-repeat-count, simple-trigger-reschedule-now-with-remaining-repeat-count, simple-trigger-reschedule-next-with-existing-count and simple-trigger-reschedule-next-with-remaining-count.

Creating a REST resource and a test

Create the org.acme.quartz.TaskResource class with the following content:

package org.acme.quartz;

import java.util.List;

import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;

@Path("/tasks")
public class TaskResource {

    @GET
    public List<Task> listAll() {
        return Task.listAll(); (1)
    }
}
1 Retrieve the list of created tasks from the database

You also have the option to create a org.acme.quartz.TaskResourceTest test with the following content:

package org.acme.quartz;

import io.quarkus.test.junit.QuarkusTest;

import static org.hamcrest.Matchers.greaterThanOrEqualTo;

import org.junit.jupiter.api.Test;

import static io.restassured.RestAssured.given;
import static org.hamcrest.CoreMatchers.is;

@QuarkusTest
public class TaskResourceTest {

    @Test
    public void tasks() throws InterruptedException {
        Thread.sleep(1000); // wait at least a second to have the first task created
        given()
                .when().get("/tasks")
                .then()
                .statusCode(200)
                .body("size()", is(greaterThanOrEqualTo(1))); (1)
    }
}
1 Ensure that we have a 200 response and at least one task created

Creating Quartz Tables

Add a SQL migration file named src/main/resources/db/migration/V2.0.0__QuarkusQuartzTasks.sql with the content copied from file with the content from V2.0.0__QuarkusQuartzTasks.sql.

Configuring the load balancer

In the root directory, create a nginx.conf file with the following content:

user  nginx;

events {
    worker_connections   1000;
}

http {
        server {
              listen 8080;
              location / {
                proxy_pass http://tasks:8080; (1)
              }
        }
}
1 Route all traffic to our tasks application

Setting Application Deployment

In the root directory, create a docker-compose.yml file with the following content:

version: '3'

services:
  tasks: (1)
    image: quarkus-quickstarts/quartz:1.0
    build:
      context: ./
      dockerfile: src/main/docker/Dockerfile.${QUARKUS_MODE:-jvm}
    environment:
      QUARKUS_DATASOURCE_URL: jdbc:postgresql://postgres/quarkus_test
    networks:
      - tasks-network
    depends_on:
      - postgres

  nginx: (2)
    image: nginx:1.17.6
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    depends_on:
      - tasks
    ports:
      - 8080:8080
    networks:
      - tasks-network

  postgres: (3)
    image: postgres:14.1
    container_name: quarkus_test
    environment:
      - POSTGRES_USER=quarkus_test
      - POSTGRES_PASSWORD=quarkus_test
      - POSTGRES_DB=quarkus_test
    ports:
      - 5432:5432
    networks:
      - tasks-network

networks:
  tasks-network:
    driver: bridge
1 Define the tasks service
2 Define the nginx load balancer to route incoming traffic to an appropriate node
3 Define the configuration to run the database

Running the database

In a separate terminal, run the below command:

docker-compose up postgres (1)
1 Start the database instance using the configuration options supplied in the docker-compose.yml file

Run the application in Dev Mode

Run the application with:

CLI
quarkus dev
Maven
./mvnw quarkus:dev
Gradle
./gradlew --console=plain quarkusDev

After a few seconds, open another terminal and run curl localhost:8080/tasks to verify that we have at least one task created.

As usual, the application can be packaged using:

CLI
quarkus build
Maven
./mvnw install
Gradle
./gradlew build

and executed with java -jar target/quarkus-app/quarkus-run.jar.

You can also generate the native executable with:

CLI
quarkus build --native
Maven
./mvnw install -Dnative
Gradle
./gradlew build -Dquarkus.native.enabled=true

Packaging the application and run several instances

The application can be packaged using:

CLI
quarkus build
Maven
./mvnw install
Gradle
./gradlew build

Once the build is successful, run the below command:

docker-compose up --scale tasks=2 --scale nginx=1 (1)
1 Start two instances of the application and a load balancer

After a few seconds, in another terminal, run curl localhost:8080/tasks to verify that tasks were only created at different instants and in an interval of 10 seconds.

You can also generate the native executable with:

CLI
quarkus build --native
Maven
./mvnw install -Dnative
Gradle
./gradlew build -Dquarkus.native.enabled=true
It’s the responsibility of the deployer to clear/remove the previous state, i.e. stale jobs and triggers. Moreover, the applications that form the "Quartz cluster" should be identical, otherwise an unpredictable result may occur.

Configuring the Instance ID

By default, the scheduler is configured with a simple instance ID generator using the machine hostname and the current timestamp, so you don’t need to worry about setting a appropriate instance-id for each node when running in clustered mode. However, you can define a specific instance-id by yourself setting a configuration property reference or using other generators.

quarkus.quartz.instance-id=${HOST:AUTO} (1)
1 This will expand the HOST environment variable and use AUTO as the default value if HOST is not set.

The example below configure the generator org.quartz.simpl.HostnameInstanceIdGenerator named as hostname, so you can use its name as instance-id to be used. That generator uses just the machine hostname and can be appropriate in environments providing unique names for the nodes.

quarkus.quartz.instance-id=hostname
quarkus.quartz.instance-id-generators.hostname.class=org.quartz.simpl.HostnameInstanceIdGenerator
It’s the responsibility of the deployer to define appropriate instance identifiers. Moreover, the applications that form the "Quartz cluster" should contain unique instance identifiers, otherwise an unpredictable result may occur. It’s recommended to use an appropriate instance ID generator rather than specifying explicit identifiers.

Registering Plugin and Listeners

You can register plugins, job-listeners and trigger-listeners through Quarkus configuration.

The example below registers the plugin org.quartz.plugins.history.LoggingJobHistoryPlugin named as jobHistory with the property jobSuccessMessage defined as Job [{1}.{0}] execution complete and reports: {8}

quarkus.quartz.plugins.jobHistory.class=org.quartz.plugins.history.LoggingJobHistoryPlugin
quarkus.quartz.plugins.jobHistory.properties.jobSuccessMessage=Job [{1}.{0}] execution complete and reports: {8}

You can also register a listener programmatically with an injected org.quartz.Scheduler:

public class MyListenerManager {
    void onStart(@Observes StartupEvent event, org.quartz.Scheduler scheduler) throws SchedulerException {
        scheduler.getListenerManager().addJobListener(new MyJogListener());
        scheduler.getListenerManager().addTriggerListener(new MyTriggerListener());
    }
}

Run scheduled methods on virtual threads

Methods annotated with @Scheduled can also be annotated with @RunOnVirtualThread. In this case, the method is invoked on a virtual thread.

The method must return void and your Java runtime must provide support for virtual threads. Read the virtual thread guide for more details.

This feature cannot be combined with the run-blocking-method-on-quartz-thread option. If run-blocking-method-on-quartz-thread is set, the scheduled method runs on a (platform) thread managed by Quartz.

Quartz Configuration Reference