[[io.quartz]]
= Quartz Scheduler

Spring Boot offers several conveniences for working with the https://www.quartz-scheduler.org/[Quartz scheduler], including the `spring-boot-starter-quartz` starter.
If Quartz is available, a javadoc:org.quartz.Scheduler[] is auto-configured (through the javadoc:org.springframework.scheduling.quartz.SchedulerFactoryBean[] abstraction).

Beans of the following types are automatically picked up and associated with the javadoc:org.quartz.Scheduler[]:

* javadoc:org.quartz.JobDetail[]: defines a particular Job.
  javadoc:org.quartz.JobDetail[] instances can be built with the javadoc:org.quartz.JobBuilder[] API.
* javadoc:org.quartz.Calendar[].
* javadoc:org.quartz.Trigger[]: defines when a particular job is triggered.

By default, an in-memory javadoc:org.quartz.spi.JobStore[] is used.
However, it is possible to configure a JDBC-based store if a javadoc:javax.sql.DataSource[] bean is available in your application and if the configprop:spring.quartz.job-store-type[] property is configured accordingly, as shown in the following example:

[configprops,yaml]
----
spring:
  quartz:
    job-store-type: "jdbc"
----

When the JDBC store is used, the schema can be initialized on startup, as shown in the following example:

[configprops,yaml]
----
spring:
  quartz:
    jdbc:
      initialize-schema: "always"
----

WARNING: By default, the database is detected and initialized by using the standard scripts provided with the Quartz library.
These scripts drop existing tables, deleting all triggers on every restart.
To use a custom script, set the configprop:spring.quartz.jdbc.schema[] property.
Some of the standard scripts – such as those for SQL Server, Azure SQL, and Sybase – cannot be used without modification.
In these cases, make a copy of the script and edit it as directed in the script's comments then set configprop:spring.quartz.jdbc.schema[] to use your customized script.

To have Quartz use a javadoc:javax.sql.DataSource[] other than the application's main javadoc:javax.sql.DataSource[], declare a javadoc:javax.sql.DataSource[] bean, annotating its javadoc:org.springframework.context.annotation.Bean[format=annotation] method with javadoc:org.springframework.boot.quartz.autoconfigure.QuartzDataSource[format=annotation].
Doing so ensures that the Quartz-specific javadoc:javax.sql.DataSource[] is used by both the javadoc:org.springframework.scheduling.quartz.SchedulerFactoryBean[] and for schema initialization.
Similarly, to have Quartz use a javadoc:org.springframework.transaction.TransactionManager[] other than the application's main javadoc:org.springframework.transaction.TransactionManager[] declare a javadoc:org.springframework.transaction.TransactionManager[] bean, annotating its javadoc:org.springframework.context.annotation.Bean[format=annotation] method with javadoc:org.springframework.boot.quartz.autoconfigure.QuartzTransactionManager[format=annotation].

By default, jobs created by configuration will not overwrite already registered jobs that have been read from a persistent job store.
To enable overwriting existing job definitions set the configprop:spring.quartz.overwrite-existing-jobs[] property.

Quartz Scheduler configuration can be customized using `spring.quartz` properties and javadoc:org.springframework.boot.quartz.autoconfigure.SchedulerFactoryBeanCustomizer[] beans, which allow programmatic javadoc:org.springframework.scheduling.quartz.SchedulerFactoryBean[] customization.
Advanced Quartz configuration properties can be customized using `spring.quartz.properties.*`.

NOTE: In particular, an javadoc:java.util.concurrent.Executor[] bean is not associated with the scheduler as Quartz offers a way to configure the scheduler through `spring.quartz.properties`.
If you need to customize the task executor, consider implementing javadoc:org.springframework.boot.quartz.autoconfigure.SchedulerFactoryBeanCustomizer[].

Jobs can define setters to inject data map properties.
Regular beans can also be injected in a similar manner, as shown in the following example:

include-code::MySampleJob[]
