Spring Boot @Order
last modified July 21, 2023
Spring Boot @Order tutorial shows how to order beans with @Order annotation.
Spring is a popular Java application framework and Spring Boot is an evolution of Spring that helps create stand-alone, production-grade Spring based applications easily.
@Order
@Order defines the sort order for an annotated component. The
value is optional and represents an order value. Lower values have
higher priority.
Spring Boot @Order example
The following application orders the execution of beans implementing
CommandLineRunner.
build.gradle
...
src
├───main
│ ├───java
│ │ └───com
│ │ └───zetcode
│ │ Application.java
│ │ MyRunner.java
│ │ MyRunner2.java
│ └───resources
└───test
└───java
This is the project structure.
plugins {
id 'org.springframework.boot' version '3.1.1'
id 'io.spring.dependency-management' version '1.1.0'
id 'java'
}
group = 'com.zetcode'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'
repositories {
mavenCentral()
}
dependencies {
implementation 'org.springframework.boot:spring-boot-starter'
}
This is the Gradle build file.
package com.zetcode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.CommandLineRunner;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
@Component
@Order(value = 2)
public class MyRunner implements CommandLineRunner {
private static final Logger logger = LoggerFactory.getLogger(MyRunner.class);
@Override
public void run(String... args) {
logger.info("Running MyRunner");
}
}
The bean is started when the application starts. With the @Order
annotation we give it a priority level.
package com.zetcode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.CommandLineRunner;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
@Component
@Order(value = 1)
public class MyRunner2 implements CommandLineRunner {
private static final Logger logger = LoggerFactory.getLogger(MyRunner2.class);
@Override
public void run(String... args) {
logger.info("Running MyRunner2");
}
}
This is MyRunner2. It has a higher priority set with @Order,
so it is executed before MyRunner.
package com.zetcode;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
Application is the entry point which sets up Spring Boot
application.
$ ./gradlew bootRun ... ... com.zetcode.MyRunner2 : Running MyRunner2 ... com.zetcode.MyRunner : Running MyRunner
We run the application.
In this article we have shown how to use @Order annotation to set
the order of execution of beans.