在 Spring Boot 中显示自动配置报告

baeldung 2024-01-08

1. 概述

Spring Boot 的自动配置机制会根据应用程序的依赖项尝试自动配置应用。

在本篇快速教程中，我们将了解如何让 Spring Boot 在启动时记录其自动配置报告。

2. 示例应用程序

让我们编写一个简单的 Spring Boot 应用程序，用于后续示例：

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

3. 使用 application.properties 配置方式

启动该应用程序时，默认不会输出太多关于 Spring Boot 如何或为何决定组合应用程序配置的信息。

但我们只需在 application.properties 文件中启用调试模式，即可让 Spring Boot 生成一份自动配置报告：

debug=true

或者，在 application.yml 文件中：

debug: true

4. 命令行方式

如果我们不想使用配置文件的方式，也可以在启动应用程序时通过 --debug 参数触发自动配置报告：

$ java -jar myproject-0.0.1-SNAPSHOT.jar --debug

5. 报告输出内容

自动配置报告包含以下信息：

• Spring Boot 在类路径上找到并自动配置的类；
• Spring Boot 已知但未在类路径上找到的类。

由于我们设置了 debug=true，因此可以在控制台输出中看到如下内容：

============================
CONDITIONS EVALUATION REPORT
============================


Positive matches:
-----------------

   AopAutoConfiguration matched:
      - @ConditionalOnClass found required classes 'org.springframework.context.annotation.EnableAspectJAutoProxy', 
        'org.aspectj.lang.annotation.Aspect', 'org.aspectj.lang.reflect.Advice', 'org.aspectj.weaver.AnnotatedElement'; 
        @ConditionalOnMissingClass did not find unwanted class (OnClassCondition)
      - @ConditionalOnProperty (spring.aop.auto=true) matched (OnPropertyCondition)

   AopAutoConfiguration.CglibAutoProxyConfiguration matched:
      - @ConditionalOnProperty (spring.aop.proxy-target-class=true) matched (OnPropertyCondition)

   AuditAutoConfiguration#auditListener matched:
      - @ConditionalOnMissingBean (types: org.springframework.boot.actuate.audit.listener.AbstractAuditListener; 
        SearchStrategy: all) did not find any beans (OnBeanCondition)

   AuditAutoConfiguration.AuditEventRepositoryConfiguration matched:
      - @ConditionalOnMissingBean (types: org.springframework.boot.actuate.audit.AuditEventRepository; 
        SearchStrategy: all) did not find any beans (OnBeanCondition)

   AuditEventsEndpointAutoConfiguration#auditEventsEndpoint matched:
      - @ConditionalOnBean (types: org.springframework.boot.actuate.audit.AuditEventRepository; 
        SearchStrategy: all) found bean 'auditEventRepository'; 
        @ConditionalOnMissingBean (types: org.springframework.boot.actuate.audit.AuditEventsEndpoint; 
        SearchStrategy: all) did not find any beans (OnBeanCondition)
      - @ConditionalOnEnabledEndpoint no property management.endpoint.auditevents.enabled found 
        so using endpoint default (OnEnabledEndpointCondition)


Negative matches:
-----------------

   ActiveMQAutoConfiguration:
      Did not match:
         - @ConditionalOnClass did not find required classes 'javax.jms.ConnectionFactory', 
           'org.apache.activemq.ActiveMQConnectionFactory' (OnClassCondition)

   AopAutoConfiguration.JdkDynamicAutoProxyConfiguration:
      Did not match:
         - @ConditionalOnProperty (spring.aop.proxy-target-class=false) did not find property 
           'proxy-target-class' (OnPropertyCondition)

   ArtemisAutoConfiguration:
      Did not match:
         - @ConditionalOnClass did not find required classes 'javax.jms.ConnectionFactory', 
           'org.apache.activemq.artemis.jms.client.ActiveMQConnectionFactory' (OnClassCondition)

   AtlasMetricsExportAutoConfiguration:
      Did not match:
         - @ConditionalOnClass did not find required class 'io.micrometer.atlas.AtlasMeterRegistry' 
           (OnClassCondition)

   AtomikosJtaConfiguration:
      Did not match:
         - @ConditionalOnClass did not find required class 'com.atomikos.icatch.jta.UserTransactionManager' 
           (OnClassCondition)

6. 结论

在本篇快速教程中，我们学习了如何显示和阅读 Spring Boot 的自动配置报告。