Springboot @Order注解正确用法

@Order注解不能指定 bean 的加载顺序，它适用于 AOP 的优先级，以及将多个 Bean 注入到集合时，这些 bean 在集合中的顺序。

注意：组件类必须实现接口

package com.wenxiaowu.springboot.order.component;  import org.springframework.boot.CommandLineRunner; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component;  /**  * 测试组件order加载顺序(未实现接口，不能正确加载顺序)  */ @SpringBootApplication(scanBasePackages = {"com.wenxiaowu.springboot.order.component"}) public class ComponentOrderTest {     public static void main(String[] args) {         System.out.println("ComponentOrderTest start.");         SpringApplication.run(ComponentOrderTest.class, args);         System.out.println("ComponentOrderTest end.");     } }  @Component class Runner implements CommandLineRunner {     @Override     public void run(String... args) throws Exception {         System.out.println("The Runner start to initialize ...");     } }  @Component @Order(2) class OrderRunner1 implements CommandLineRunner {     @Override     public void run(String... args) throws Exception {         System.out.println("The OrderRunner1 start to initialize ...");     } }  @Component @Order(1) class OrderRunner2 implements CommandLineRunner {     @Override     public void run(String... args) throws Exception {         System.out.println("The OrderRunner2 start to initialize ...");     } }

package com.wenxiaowu.springboot.order.service;  import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component; import org.springframework.stereotype.Service;  import javax.annotation.PostConstruct; import java.util.List;  /**  * 测试组件order加载顺序  */ @SpringBootApplication(scanBasePackages = {"com.wenxiaowu.springboot.order.service"}) public class ServiceOrderTest {     public static void main(String[] args) {         System.out.println("ServiceOrderTest start.");         SpringApplication.run(ServiceOrderTest.class, args);         System.out.println("ServiceOrderTest end.");     } }  @Component class AfterRepairConsumer {     @Autowired     private List<RepairCreatePostConsumer> postConsumers;      @PostConstruct     public void run() {         final String repairId = "1";         if (postConsumers != null && postConsumers.size() > 0) {             postConsumers.forEach(e -> e.postHandler(repairId));         }     } }  interface RepairCreatePostConsumer {     /**      * 创建报修单后做什么      */     void postHandler(String repairId); }  @Service @Order(value = 3) class SendEmail implements RepairCreatePostConsumer {     @Override     public void postHandler(String repairId) {         System.out.println("为报修单" + repairId + "发送邮件");     } }  @Service @Order(value = 2) class SendInvoice implements RepairCreatePostConsumer {     @Override     public void postHandler(String repairId) {         System.out.println("为报修单" + repairId + "发送发票");     } }  @Service @Order(value = 1) class SendMessage implements RepairCreatePostConsumer {     @Override     public void postHandler(String repairId) {         System.out.println("为报修单" + repairId + "发送消息");     } }