选择指南版本

Scheduling Periodic Tasks

Prerequisites
Architecture
Solution
Creating the Maven project
Creating a scheduled job
Updating the application configuration file
Creating the REST resource
打包并运行该应用程序
Scheduler Configuration Reference

Modern applications often need to run specific tasks periodically. In this guide, you learn how to schedule periodic tasks.

If you need a clustered scheduler use the Quartz extension.

Prerequisites

完成这个指南，你需要:

大概15分钟
编辑器
安装JDK 11以上版本并正确配置了 JAVA_HOME
Apache Maven 3.9.1
如果你愿意的话，还可以选择使用Quarkus CLI
如果你想构建原生可执行程序，可以选择安装Mandrel或者GraalVM，并正确配置(或者使用Docker在容器中进行构建)

Architecture

In this guide, we create a straightforward application accessible using HTTP to get the current value of a counter. This counter is periodically (every 10 seconds) incremented.

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 https://github.com/quarkusio/quarkus-quickstarts.git, or download an archive.

The solution is located in the scheduler-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:scheduler-quickstart \
    --extension='resteasy-reactive,scheduler' \
    --no-code
cd scheduler-quickstart

创建Grade项目，请添加 --gradle 或者 --gradle-kotlin-dsl 参数。

关于如何安装并使用Quarkus CLI的更多信息，请参考Quarkus CLI指南。

Maven

mvn io.quarkus.platform:quarkus-maven-plugin:3.1.0.Final:create \
    -DprojectGroupId=org.acme \
    -DprojectArtifactId=scheduler-quickstart \
    -Dextensions='resteasy-reactive,scheduler' \
    -DnoCode
cd scheduler-quickstart

创建Grade项目，请添加 -DbuildTool=gradle 或者 -DbuildTool=gradle-kotlin-dsl 参数。

It generates a new project including:

a landing page accessible on http://localhost:8080
example Dockerfile files for both native and jvm modes
the application configuration file

The project also imports the RESTEasy Reactive and scheduler extensions.

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

CLI

quarkus extension add 'scheduler'

Maven

./mvnw quarkus:add-extension -Dextensions='scheduler'

Gradle

./gradlew addExtension --extensions='scheduler'

This will add the following to your build file:

pom.xml

<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-scheduler</artifactId>
</dependency>

build.gradle

implementation("io.quarkus:quarkus-scheduler")

Creating a scheduled job

In the org.acme.scheduler package, create the CounterBean class, with the following content:

package org.acme.scheduler;

import java.util.concurrent.atomic.AtomicInteger;
import jakarta.enterprise.context.ApplicationScoped;
import io.quarkus.scheduler.Scheduled;
import io.quarkus.scheduler.ScheduledExecution;

@ApplicationScoped              (1)
public class CounterBean {

    private AtomicInteger counter = new AtomicInteger();

    public int get() {  (2)
        return counter.get();
    }

    @Scheduled(every="10s")     (3)
    void increment() {
        counter.incrementAndGet(); (4)
    }

    @Scheduled(cron="0 15 10 * * ?") (5)
    void cronJob(ScheduledExecution execution) {
        counter.incrementAndGet();
        System.out.println(execution.getScheduledFireTime());
    }

    @Scheduled(cron = "{cron.expr}") (6)
    void cronJobWithExpressionInConfig() {
       counter.incrementAndGet();
       System.out.println("Cron expression configured in application.properties");
    }
}

1	Declare the bean in the application scope
2	The `get()` method allows retrieving the current value.
3	Use the `@Scheduled` annotation to instruct Quarkus to run this method every 10 seconds provided a worker thread is available (Quarkus is using 10 worker threads for the scheduler). If it is not available the method invocation should be re-scheduled by default i.e. it should be invoked as soon as possible. The invocation of the scheduled method does not depend on the status or result of the previous invocation.
4	The code is pretty straightforward. Every 10 seconds, the counter is incremented.
5	Define a job with a cron-like expression. The annotated method is executed at 10:15am every day.
6	Define a job with a cron-like expression `cron.expr` which is configurable in `application.properties`.

Updating the application configuration file

Edit the application.properties file and add the cron.expr configuration:

# By default, the syntax used for cron expressions is based on Quartz - https://www.quartz-scheduler.org/documentation/quartz-2.3.0/tutorials/crontrigger.html
# You can change the syntax using the following property:
# quarkus.scheduler.cron-type=unix
cron.expr=*/5 * * * * ?

Creating the REST resource

Create the CountResource class as follows:

package org.acme.scheduler;

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

@Path("/count")
public class CountResource {

    @Inject
    CounterBean counter;            (1)


    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String hello() {
        return "count: " + counter.get();  (2)
    }
}

1	Inject the `CounterBean`
2	返回当前计数器的值

打包并运行该应用程序

使用以下命令运行该应用程序:

CLI

quarkus dev

Maven

./mvnw quarkus:dev

Gradle

./gradlew --console=plain quarkusDev

在另一个终端，运行 curl localhost:8080/count 检查计数器的值。几秒钟后，重新运行 curl localhost:8080/count ，以验证计数器已被递增。

Observe the console to verify that the message Cron expression configured in application.properties has been displayed indicating that the cron job using an expression configured in application.properties has been triggered.

像往常一样，该应用程序能够使用以下方式进行打包:

CLI

quarkus build

Maven

./mvnw install

Gradle

./gradlew build

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

你也可以通过以下命令生成本地可执行文件:

CLI

quarkus build --native

Maven

./mvnw install -Dnative

Gradle

./gradlew build -Dquarkus.package.type=native

Scheduler Configuration Reference

Configuration property fixed at build time - All other configuration properties are overridable at runtime

Configuration property	类型	默认
`quarkus.scheduler.cron-type` The syntax used in CRON expressions. Environment variable: `QUARKUS_SCHEDULER_CRON_TYPE`	`cron4j`, `quartz`, `unix`, `spring`, `spring53`	`quartz`
`quarkus.scheduler.metrics.enabled` Scheduled task metrics will be enabled if a metrics extension is present and this value is true. Environment variable: `QUARKUS_SCHEDULER_METRICS_ENABLED`	boolean	`false`
`quarkus.scheduler.tracing.enabled` Tracing will be enabled if the OpenTelemetry extension is present and this value is true. Environment variable: `QUARKUS_SCHEDULER_TRACING_ENABLED`	boolean	`false`
`quarkus.scheduler.enabled` If schedulers are enabled. Environment variable: `QUARKUS_SCHEDULER_ENABLED`	boolean	`true`
`quarkus.scheduler.overdue-grace-period` Scheduled task will be flagged as overdue if next execution time is exceeded by this period. Environment variable: `QUARKUS_SCHEDULER_OVERDUE_GRACE_PERIOD`	Duration	`1S`
`quarkus.scheduler.start-mode` Scheduler can be started in different modes. By default, the scheduler is not started unless a `io.quarkus.scheduler.Scheduled` business method is found. Environment variable: `QUARKUS_SCHEDULER_START_MODE`	`normal`The scheduler is not started unless a `io.quarkus.scheduler.Scheduled` business method is found., tooltip:forced[The scheduler will be started even if no scheduled business methods are found. This is necessary for "pure" programmatic scheduling.], tooltip:halted[Just like the `forced` mode but the scheduler will not start triggering jobs until `Scheduler#resume()` is called. This can be useful to run some intialization logic that needs to be performed before the scheduler starts.]

Configuration property

类型

默认

quarkus.scheduler.cron-type

The syntax used in CRON expressions.

Environment variable: QUARKUS_SCHEDULER_CRON_TYPE

cron4j, quartz, unix, spring, spring53

quartz

quarkus.scheduler.metrics.enabled

Scheduled task metrics will be enabled if a metrics extension is present and this value is true.

Environment variable: QUARKUS_SCHEDULER_METRICS_ENABLED

boolean

false

quarkus.scheduler.tracing.enabled

Tracing will be enabled if the OpenTelemetry extension is present and this value is true.

Environment variable: QUARKUS_SCHEDULER_TRACING_ENABLED

boolean

false

quarkus.scheduler.enabled

If schedulers are enabled.

Environment variable: QUARKUS_SCHEDULER_ENABLED

boolean

true

quarkus.scheduler.overdue-grace-period

Scheduled task will be flagged as overdue if next execution time is exceeded by this period.

Environment variable: QUARKUS_SCHEDULER_OVERDUE_GRACE_PERIOD

Duration

1S

quarkus.scheduler.start-mode

Scheduler can be started in different modes. By default, the scheduler is not started unless a io.quarkus.scheduler.Scheduled business method is found.

Environment variable: QUARKUS_SCHEDULER_START_MODE

normalThe scheduler is not started unless a io.quarkus.scheduler.Scheduled business method is found., tooltip:forced[The scheduler will be started even if no scheduled business methods are found. This is necessary for "pure" programmatic scheduling.], tooltip:halted[Just like the forced mode but the scheduler will not start triggering jobs until Scheduler#resume() is called. This can be useful to run some intialization logic that needs to be performed before the scheduler starts.]

About the Duration format

持续时间的格式使用标准的 java.time.Duration 格式您可以在 Duration#parse() javadoc 中了解更多信息。

您还可以提供以数字开头的持续时间值。在这种情况下，如果该值仅包含一个数字，则转换器将该值视为秒。否则，PT 会隐式添加到值的前面，以获得标准的 java.time.Duration 格式。