@Component @PostConstruct @Order ApplicationRunner CommandLineRunner

@Component中static优先于@PostConstruct优先于ApplicationRunner优先于CommandLineRunner

1. @Component 优先执行
   • @Order可执行执行顺序：数字越小，优先级越高，也就是@Order(1)注解的类会在@Order(2)注解的类之前执行。
     @Order(value=1)
     @Order(value=2)
     @Order(value=3)
   • static 优先执行
   • @PostConstruct 在static完成后执行
2. @Component implements ApplicationRunner 容器启动完成后 @Component完成后 执行
3. @Component implements CommandLineRunner 容器启动完成 @Component完成后 ApplicationRunner 完成后 最后执行

代码示例

@Component @Order(value = 1) @PostConstruct

import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;

@Component
@Order(value = 1)
public class Component1 {
	
    static {
        System.out.println("

Hello @Component Order1 static
");
    }
	
    @PostConstruct
    public void start() {
        System.out.println("

Hello @Component Order1 @PostConstruct
");
    }
	
}

@Component @Order(value = 2) @PostConstruct

import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;

@Component
@Order(value = 2)
public class Component2 {
	
    static {
        System.out.println("

Hello @Component Order2 static
");
    }
	
    @PostConstruct
    public void start() {
        System.out.println("

Hello @Component Order2 @PostConstruct
");
    }
	
}

@Component implements ApplicationRunner

import org.springframework.boot.ApplicationArguments;
import org.springframework.boot.ApplicationRunner;
import org.springframework.stereotype.Component;

@Component
public class ComponentApplicationRunner implements ApplicationRunner{

    @Override
    public void run(ApplicationArguments args){
        System.out.println("

Hello @Component implements ApplicationRunner
");
    }
	
}

@Component implements CommandLineRunner

import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;

@Component
public class ComponentCommandLineRunner implements CommandLineRunner{

    @Override
    public void run(String... strings){
        System.out.println("

Hello @Component implements CommandLineRunner
");
    }
	
}