springboot配置加载顺序

1. 分别创建3个配置加载类ConfigA、ConfigB、ConfigB

package com.zsx.config;

import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.context.event.ApplicationStartedEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;

@Configuration
@AutoConfigureAfter(ConfigC.class)
public class ConfigA {

    public ConfigA() {
        System.out.println("ConfigA()");
    }

    @EventListener(ApplicationStartedEvent.class)
    public void onApplicationStarted() {
        System.out.println("ConfigA.onApplicationStarted()");
    }
}

package com.zsx.config;

import org.springframework.boot.autoconfigure.AutoConfigureBefore;
import org.springframework.boot.context.event.ApplicationStartedEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;

import java.util.concurrent.TimeUnit;

@Configuration
@AutoConfigureBefore(ConfigC.class)
public class ConfigB {

    public ConfigB() throws InterruptedException {
        TimeUnit.SECONDS.sleep(3);
        System.out.println("ConfigB()");
    }

    @EventListener(ApplicationStartedEvent.class)
    public void onApplicationStarted() throws InterruptedException {
        TimeUnit.SECONDS.sleep(3);
        System.out.println("ConfigB.onApplicationStarted()");
    }
}

package com.zsx.config;

import org.springframework.boot.context.event.ApplicationStartedEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;

import java.util.concurrent.TimeUnit;

@Configuration
public class ConfigC {

    public ConfigC() throws InterruptedException {
        TimeUnit.SECONDS.sleep(2);
        System.out.println("ConfigC()");
    }

    @EventListener(ApplicationStartedEvent.class)
    public void onApplicationStarted() throws InterruptedException {
        TimeUnit.SECONDS.sleep(2);
        System.out.println("ConfigC.onApplicationStarted()");
    }
}

2. 在资源文件夹下创建文件resources/META-INF/spring.factories，文件内容为

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.zsx.config.ConfigA,\
com.zsx.config.ConfigB,\
com.zsx.config.ConfigC

3. 创建引导类并启动

package com.zsx;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class MyTestApplication {

    public static void main(String[] args) {
        SpringApplication.run(MyTestApplication.class, args);
    }

}

4. 按照自定义配置分析，加载顺序应该为B->C->A，查看结果

E:\jdk\jdk-13.0.1\bin\java.exe -XX:TieredStopAtLevel=1 -noverify -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-javaagent:E:\JetBrains\IntelliJ IDEA 2019.2.3\lib\idea_rt.jar=52073:E:\JetBrains\IntelliJ IDEA 2019.2.3\bin" -Dfile.encoding=UTF-8 -classpath D:\MyIdeaProjects\my-test\target\classes;E:\maven\repository\org\springframework\boot\spring-boot-starter-web\2.2.0.RELEASE\spring-boot-starter-web-2.2.0.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter\2.2.0.RELEASE\spring-boot-starter-2.2.0.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-logging\2.2.0.RELEASE\spring-boot-starter-logging-2.2.0.RELEASE.jar;E:\maven\repository\ch\qos\logback\logback-classic\1.2.3\logback-classic-1.2.3.jar;E:\maven\repository\ch\qos\logback\logback-core\1.2.3\logback-core-1.2.3.jar;E:\maven\repository\org\apache\logging\log4j\log4j-to-slf4j\2.12.1\log4j-to-slf4j-2.12.1.jar;E:\maven\repository\org\apache\logging\log4j\log4j-api\2.12.1\log4j-api-2.12.1.jar;E:\maven\repository\org\slf4j\jul-to-slf4j\1.7.28\jul-to-slf4j-1.7.28.jar;E:\maven\repository\jakarta\annotation\jakarta.annotation-api\1.3.5\jakarta.annotation-api-1.3.5.jar;E:\maven\repository\org\yaml\snakeyaml\1.25\snakeyaml-1.25.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-json\2.2.0.RELEASE\spring-boot-starter-json-2.2.0.RELEASE.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-databind\2.10.0\jackson-databind-2.10.0.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-annotations\2.10.0\jackson-annotations-2.10.0.jar;E:\maven\repository\com\fasterxml\jackson\core\jackson-core\2.10.0\jackson-core-2.10.0.jar;E:\maven\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.10.0\jackson-datatype-jdk8-2.10.0.jar;E:\maven\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.10.0\jackson-datatype-jsr310-2.10.0.jar;E:\maven\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.10.0\jackson-module-parameter-names-2.10.0.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-tomcat\2.2.0.RELEASE\spring-boot-starter-tomcat-2.2.0.RELEASE.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-core\9.0.27\tomcat-embed-core-9.0.27.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-el\9.0.27\tomcat-embed-el-9.0.27.jar;E:\maven\repository\org\apache\tomcat\embed\tomcat-embed-websocket\9.0.27\tomcat-embed-websocket-9.0.27.jar;E:\maven\repository\org\springframework\boot\spring-boot-starter-validation\2.2.0.RELEASE\spring-boot-starter-validation-2.2.0.RELEASE.jar;E:\maven\repository\jakarta\validation\jakarta.validation-api\2.0.1\jakarta.validation-api-2.0.1.jar;E:\maven\repository\org\hibernate\validator\hibernate-validator\6.0.17.Final\hibernate-validator-6.0.17.Final.jar;E:\maven\repository\org\jboss\logging\jboss-logging\3.4.1.Final\jboss-logging-3.4.1.Final.jar;E:\maven\repository\com\fasterxml\classmate\1.5.0\classmate-1.5.0.jar;E:\maven\repository\org\springframework\spring-web\5.2.0.RELEASE\spring-web-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-beans\5.2.0.RELEASE\spring-beans-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-webmvc\5.2.0.RELEASE\spring-webmvc-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-aop\5.2.0.RELEASE\spring-aop-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-context\5.2.0.RELEASE\spring-context-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-expression\5.2.0.RELEASE\spring-expression-5.2.0.RELEASE.jar;E:\maven\repository\org\slf4j\slf4j-api\1.7.28\slf4j-api-1.7.28.jar;E:\maven\repository\org\springframework\spring-core\5.2.0.RELEASE\spring-core-5.2.0.RELEASE.jar;E:\maven\repository\org\springframework\spring-jcl\5.2.0.RELEASE\spring-jcl-5.2.0.RELEASE.jar;E:\maven\repository\org\glassfish\jaxb\jaxb-core\2.3.0.1\jaxb-core-2.3.0.1.jar;E:\maven\repository\javax\xml\bind\jaxb-api\2.3.1\jaxb-api-2.3.1.jar;E:\maven\repository\javax\activation\javax.activation-api\1.2.0\javax.activation-api-1.2.0.jar;E:\maven\repository\org\glassfish\jaxb\txw2\2.3.2\txw2-2.3.2.jar;E:\maven\repository\com\sun\istack\istack-commons-runtime\3.0.5\istack-commons-runtime-3.0.5.jar;E:\maven\repository\com\sun\xml\bind\jaxb-impl\2.3.2\jaxb-impl-2.3.2.jar;E:\maven\repository\org\springframework\boot\spring-boot-devtools\2.2.0.RELEASE\spring-boot-devtools-2.2.0.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot\2.2.0.RELEASE\spring-boot-2.2.0.RELEASE.jar;E:\maven\repository\org\springframework\boot\spring-boot-autoconfigure\2.2.0.RELEASE\spring-boot-autoconfigure-2.2.0.RELEASE.jar com.zsx.MyTestApplication
Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8
Java HotSpot(TM) 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.0.RELEASE)

2020-04-20 18:29:08.439  INFO 9836 --- [  restartedMain] com.zsx.MyTestApplication                : Starting MyTestApplication on zsx with PID 9836 (D:\MyIdeaProjects\my-test\target\classes started by 18273 in D:\MyIdeaProjects\my-test)
2020-04-20 18:29:08.442  INFO 9836 --- [  restartedMain] com.zsx.MyTestApplication                : No active profile set, falling back to default profiles: default
2020-04-20 18:29:08.474  INFO 9836 --- [  restartedMain] o.s.b.devtools.restart.ChangeableUrls    : The Class-Path manifest attribute in E:\maven\repository\org\glassfish\jaxb\jaxb-core\2.3.0.1\jaxb-core-2.3.0.1.jar referenced one or more files that do not exist: file:/E:/maven/repository/org/glassfish/jaxb/jaxb-core/2.3.0.1/jaxb-api-2.3.0.jar,file:/E:/maven/repository/org/glassfish/jaxb/jaxb-core/2.3.0.1/txw2-2.3.0.1.jar,file:/E:/maven/repository/org/glassfish/jaxb/jaxb-core/2.3.0.1/istack-commons-runtime-3.0.5.jar
2020-04-20 18:29:08.475  INFO 9836 --- [  restartedMain] o.s.b.devtools.restart.ChangeableUrls    : The Class-Path manifest attribute in E:\maven\repository\com\sun\xml\bind\jaxb-impl\2.3.2\jaxb-impl-2.3.2.jar referenced one or more files that do not exist: file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/jaxb-runtime-2.3.2.jar,file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/txw2-2.3.2.jar,file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/istack-commons-runtime-3.0.8.jar,file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/stax-ex-1.8.1.jar,file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/FastInfoset-1.2.16.jar,file:/E:/maven/repository/com/sun/xml/bind/jaxb-impl/2.3.2/jakarta.activation-api-1.2.1.jar
2020-04-20 18:29:08.475  INFO 9836 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2020-04-20 18:29:08.475  INFO 9836 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2020-04-20 18:29:08.948  INFO 9836 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2020-04-20 18:29:08.953  INFO 9836 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2020-04-20 18:29:08.953  INFO 9836 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.27]
2020-04-20 18:29:08.994  INFO 9836 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2020-04-20 18:29:08.994  INFO 9836 --- [  restartedMain] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 519 ms
2020-04-20 18:29:09.073  INFO 9836 --- [  restartedMain] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
ConfigB()
ConfigC()
ConfigA()
2020-04-20 18:29:14.145  INFO 9836 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
2020-04-20 18:29:14.267  INFO 9836 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2020-04-20 18:29:14.269  INFO 9836 --- [  restartedMain] com.zsx.MyTestApplication                : Started MyTestApplication in 5.998 seconds (JVM running for 6.436)
ConfigB.onApplicationStarted()
ConfigC.onApplicationStarted()
ConfigA.onApplicationStarted()

5. 运行结果跟分析结果一致，到此配置顺序成功

原文链接：https://blog.csdn.net/zsx18273117003/article/details/105641141