Using the ApplicationRunner or CommandLineRunner
If you need to run some specific code once the SpringApplication
has started, you can implement the ApplicationRunner
or CommandLineRunner
interfaces.
Both interfaces work in the same way and offer a single run
method, which is called just before SpringApplication.run(…)
completes.
This contract is well suited for tasks that should run after application startup but before it starts accepting traffic. |
The CommandLineRunner
interfaces provides access to application arguments as a string array, whereas the ApplicationRunner
uses the ApplicationArguments
interface discussed earlier.
The following example shows a CommandLineRunner
with a run
method:
-
Java
-
Kotlin
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;
@Component
public class MyCommandLineRunner implements CommandLineRunner {
@Override
public void run(String... args) {
// Do something...
}
}
import org.springframework.boot.CommandLineRunner
import org.springframework.stereotype.Component
@Component
class MyCommandLineRunner : CommandLineRunner {
override fun run(vararg args: String) {
// Do something...
}
}
If several CommandLineRunner
or ApplicationRunner
beans are defined that must be called in a specific order, you can additionally implement the org.springframework.core.Ordered
interface or use the org.springframework.core.annotation.Order
annotation.