Spring framework has built in support for scheduled tasks. Here are some examples of spring cron jobs using both annotations and xml configurations.
Download full example > spring cron example (8162 downloads )
@Scheduled Annotation
You can use @Scheduled annotation to schedule a task very easily. Below are four simple examples to show how to run cron jobs using spring annotations.
Annotation.java
package com.mycuteblog.spring.schedule;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;
import java.util.Date;
@Service
@EnableScheduling
public class Annotation {
@Scheduled(fixedDelay = 5000)
public void fixedDelayTask() {
System.out.println(new Date() + " This runs in a fixed delay");
}
@Scheduled(fixedRate = 6000)
public void fixedRateTask() {
System.out.println(new Date() + " This runs in a fixed rate");
}
@Scheduled(fixedRate = 7000, initialDelay = 2000)
public void fixedRateWithInitialDelayTask(){
System.out.println(new Date() + " This runs in a fixed delay with a initial delay");
}
@Scheduled(cron = "10 * * * * *")
public void cronTask(){
System.out.println(new Date() + " This runs in a cron schedule");
}
}
fixedDelay: Run tasks with a fixed delay(in example it’s 5 seconds) between last task end time and next task start time. For example, if task starts at 11:00:00 and it takes 3 seconds to execute next task starts at 11:00:08.
fixedRate: Run tasks with a fixed rate of given time. For example in above example
fixedRateTask() is called every 6 seconds. (ie: 11:00:00, 11:00:06, 11:00:12, …)
initialDelay: This can be used with above examples. This property sets delay for first time run. For example, if program starts at 11:00:00 fixedRateWithInitialDelayTask() will run at 11:00:02, 11:00:09, 11:00:16, …
cron: This can be any cron expression.
output
xml Configuration
A cron job can be set using xml configurations too. Following example shows how you can set above cron jobs using xml.
Xml.java
package com.mycuteblog.spring.schedule;
import java.util.Date;
public class Xml {
public void xmlFixedDelayTask() {
System.out.println(new Date() + " This task runs in fixed delay by xml configuration");
}
public void xmlFixedRateTask() {
System.out.println(new Date() + " This task runs in fixed rate by xml configuration");
}
public void xmlCronTask() {
System.out.println(new Date() + " This task runs in a cron schedule by xml configuration");
}
}
spring.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/springcontext.xsd
http://www.springframework.org/schema/task
http://www.springframework.org/schema/task/spring-task.xsd">
<context:component-scan base-package="com.mycuteblog.spring" />
<bean id="xmlScheduledTasks" class="com.mycuteblog.spring.schedule.Xml" />
<task:scheduler id="taskScheduler" pool-size="10" />
<task:scheduled-tasks>
<task:scheduled ref="xmlScheduledTasks" method="xmlFixedDelayTask" fixed-delay="8000"/>
<task:scheduled ref="xmlScheduledTasks" method="xmlFixedRateTask" fixed-rate="10000"/>
<task:scheduled ref="xmlScheduledTasks" method="xmlCronTask" cron="15 * * * * *"/>
</task:scheduled-tasks>
</beans>
I have used maven to build the project. Here is the pom.xml configuration.
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mycuteblog</groupId>
<artifactId>spring-schedule</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.0.6.RELEASE</version>
</dependency>
</dependencies>
<!--configurations to run project standalone-->
</project>
Finally here is the main class to test above examples.
SpringScheduleDemo.java
package com.mycuteblog.spring.schedule;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class SpringScheduleDemo {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("spring.xml");
}
}
output
Download full example > spring cron example (8162 downloads )
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