借鉴：
这个链接是包含run方法进来debug看整个过程的，建议先看：https://www.cnblogs.com/starsray/p/15580915.html
https://blog.csdn.net/fengxiandada/article/details/130080828
Springboot自动装配
1.创建springboot应用
如何创建一个spring boot应用？这就很简单了，可以使用idea自带的spring initializr帮助我们选择相应的场景启动器也就是starter，快速创建应用，也可以访问spring官方网站来创建应用。
2.自动装配原理
Spring Boot的自动装配主要依靠注解和相关实现来完成，这里从注解开始进行逐层分析，主程序注解@SpringBootApplication，这个注解是一个合成注解，包含以下三个注解：
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan(excludeFilters = { @Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class),
@Filter(type = FilterType.CUSTOM, classes = AutoConfigurationExcludeFilter.class) })
public @interface SpringBootApplication {
************************************省略
}
@SpringBootConfiguration
通过源码可以看到这个注解内部只包含一个@Configuration注解，来标注这是这个配置类。
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Configuration
@Indexed
public @interface SpringBootConfiguration {
@AliasFor(
annotation = Configuration.class
)
boolean proxyBeanMethods() default true;
}
@ComponentScan
这个注解主要进行标注一个Spring Boot应用的包扫描范围，默认扫描组件包含主程序所在的同一级别或者子包所在的范围。 包路径默认规则由AutoConfigurationExcludeFilter类来实现。
@EnableAutoConfiguration
Spring Boot自动配置的功能主要由这个注解来实现，实现自动加载不同的场景依赖，查看源码
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@AutoConfigurationPackage
@Import({AutoConfigurationImportSelector.class})
public @interface EnableAutoConfiguration {
String ENABLED_OVERRIDE_PROPERTY = "spring.boot.enableautoconfiguration";
Class<?>[] exclude() default {};
String[] excludeName() default {};
}
这里包含了@AutoConfigurationPackage注解和导入了一个类，这里属于@Import注解的高级用法，先查看@AutoConfigurationPackage这个注解的源码
@AutoConfigurationPackage
注解@Import导入了一个类通过一个Registrar来对包进行自动配置，查看Registrar源码内容
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@Import({Registrar.class})
public @interface AutoConfigurationPackage {
String[] basePackages() default {};
Class<?>[] basePackageClasses() default {};
}
Registrar.java
static class Registrar implements ImportBeanDefinitionRegistrar, DeterminableImports {
Registrar() {
}
public void registerBeanDefinitions(AnnotationMetadata metadata, BeanDefinitionRegistry registry) {
AutoConfigurationPackages.register(registry, (String[])(new AutoConfigurationPackages.PackageImports(metadata)).getPackageNames().toArray(new String[0]));
}
public Set<Object> determineImports(AnnotationMetadata metadata) {
return Collections.singleton(new AutoConfigurationPackages.PackageImports(metadata));
}
}
也就是说当SpringBoot应用启动时默认会将启动类所在的package作为自动配置的package，来扫描加载应用内部的组件，如果包名需要自定义这时就可以使用@ComponentScan注解来指定。
除了自动包管理之外，Spring Boot应用在启动时还有默认组件需要进行加载，这里主要依靠@EnableAutoConfiguration注解中导入的AutoConfigurationImportSelector类来完成。查看主要源码流程。
AutoConfigurationImportSelector.java
通过selectImports方法来返回需要加载的自动配置类组件数组。
通过getAutoConfigurationEntry方法获取需要被自动配置的entry信息
/**
* @author Phillip Webb
* @author Andy Wilkinson
*/
public class AutoConfigurationImportSelector implements DeferredImportSelector, BeanClassLoaderAware,
ResourceLoaderAware, BeanFactoryAware, EnvironmentAware, Ordered {
private static final AutoConfigurationEntry EMPTY_ENTRY = new AutoConfigurationEntry();
private static final String[] NO_IMPORTS = {};
private static final Log logger = LogFactory.getLog(AutoConfigurationImportSelector.class);
private static final String PROPERTY_NAME_AUTOCONFIGURE_EXCLUDE = "spring.autoconfigure.exclude";
*********************************************省略
//重点：通过selectImports方法来返回需要加载的自动配置类组件数组。
@Override
public String[] selectImports(AnnotationMetadata annotationMetadata) {
if (!isEnabled(annotationMetadata)) {
return NO_IMPORTS;
}
AutoConfigurationEntry autoConfigurationEntry = getAutoConfigurationEntry(annotationMetadata);
return StringUtils.toStringArray(autoConfigurationEntry.getConfigurations());
}
//重点：通过getAutoConfigurationEntry方法获取需要被自动配置的entry信息
protected AutoConfigurationEntry getAutoConfigurationEntry(AnnotationMetadata annotationMetadata) {
if (!isEnabled(annotationMetadata)) {
return EMPTY_ENTRY;
}
AnnotationAttributes attributes = getAttributes(annotationMetadata);
List<String> configurations = getCandidateConfigurations(annotationMetadata, attributes);
configurations = removeDuplicates(configurations);
Set<String> exclusions = getExclusions(annotationMetadata, attributes);
checkExcludedClasses(configurations, exclusions);
configurations.removeAll(exclusions);
configurations = getConfigurationClassFilter().filter(configurations);
fireAutoConfigurationImportEvents(configurations, exclusions);
return new AutoConfigurationEntry(configurations, exclusions);
}
protected List<String> getCandidateConfigurations(AnnotationMetadata metadata, AnnotationAttributes attributes) {
List<String> configurations = SpringFactoriesLoader.loadFactoryNames(getSpringFactoriesLoaderFactoryClass(),
getBeanClassLoader());
Assert.notEmpty(configurations, "No auto configuration classes found in META-INF/spring.factories. If you "
+ "are using a custom packaging, make sure that file is correct.");
return configurations;
}
}
SpringFactoriesLoader.java
获取候选加载的组件信息，通过代码追踪可以看到，在应用启动过程中，Spring Boot会默认加载classpath下META-INF/spring.factories中所配置的entry信息。
通过loadFactoryNames方法来加载自动配置类信息
此处可以看到从META-INF/spring.factories文件中获取需要被加载的配置信息
public final class SpringFactoriesLoader {
public static final String FACTORIES_RESOURCE_LOCATION = "META-INF/spring.factories";
private static final Log logger = LogFactory.getLog(SpringFactoriesLoader.class);
public static List<String> loadFactoryNames(Class<?> factoryType, @Nullable ClassLoader classLoader) {
String factoryTypeName = factoryType.getName();
return loadSpringFactories(classLoader).getOrDefault(factoryTypeName, Collections.emptyList());
}
}
private static Map<String, List<String>> loadSpringFactories(@Nullable ClassLoader classLoader) {
MultiValueMap<String, String> result = cache.get(classLoader);
if (result != null) {
return result;
}
try {
Enumeration<URL> urls = (classLoader != null ?
classLoader.getResources(FACTORIES_RESOURCE_LOCATION) :
ClassLoader.getSystemResources(FACTORIES_RESOURCE_LOCATION));
result = new LinkedMultiValueMap<>();
while (urls.hasMoreElements()) {
URL url = urls.nextElement();
UrlResource resource = new UrlResource(url);
Properties properties = PropertiesLoaderUtils.loadProperties(resource);
for (Map.Entry<?, ?> entry : properties.entrySet()) {
String factoryTypeName = ((String) entry.getKey()).trim();
for (String factoryImplementationName : StringUtils.commaDelimitedListToStringArray((String) entry.getValue())) {
result.add(factoryTypeName, factoryImplementationName.trim());
}
}
}
cache.put(classLoader, result);
return result;
}
catch (IOException ex) {
throw new IllegalArgumentException("Unable to load factories from location [" +
FACTORIES_RESOURCE_LOCATION + "]", ex);
}
}
其中Spring Boot starter所包含的127个场景启动器都被写入在spring.factories中，这些就是需要在项目启动时被加载的entry信息，包括常见的AOP组件，Spring MVC组件，如果是web应用在项目启动时会使用默认配置被加载到Spring容器中。但是这么多组件都会被加载吗？并不是，这里只是列举出来需要被自动配置的组件信息，具体什么时候加载，Spring Boot会按需加载。这里以AOP和RabbitMQ的自配配置为例。
例子：AOP自动配置：查看源码AopAutoConfiguration
AopAutoConfiguration加载流程可以看：https://blog.csdn.net/jy02268879/article/details/88370380
这里说明了只有当配置文件中注解@ConditionalOnProperty指定了属性spring.aop.auto为true时，并且不指定也默认为true，从这里也可以看出AOP配置组件是默认生效的。
@ConditionalOnProperty：简单来讲，一般是在配置类上或者是@Bean修饰的方法上，添加此注解表示一个类是否要被Spring上下文加载，若满足条件则加载，若不满足条件则不加载。
我们在application.properties中配置的各种配置，添加配置之后即生效，就是这么控制的。
prefix：配置文件中的前缀。
name：配置的名字。
havingValue：它的值与配置文件的值对比，当两个值相同，类会被加载到spring的IOC容器中。
matchIfMissing：缺少该配置时是否可以加载，如果为true，没有该配置属性时也会正常加载，反之则不会生效。
@Configuration(proxyBeanMethods = false)
@ConditionalOnProperty(prefix = "spring.aop", name = "auto", havingValue = "true", matchIfMissing = true)
public class AopAutoConfiguration {
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(Advice.class)
static class AspectJAutoProxyingConfiguration {
@Configuration(proxyBeanMethods = false)
@EnableAspectJAutoProxy(proxyTargetClass = false)
@ConditionalOnProperty(prefix = "spring.aop", name = "proxy-target-class", havingValue = "false",
matchIfMissing = false)
static class JdkDynamicAutoProxyConfiguration {
}
@Configuration(proxyBeanMethods = false)
@EnableAspectJAutoProxy(proxyTargetClass = true)
@ConditionalOnProperty(prefix = "spring.aop", name = "proxy-target-class", havingValue = "true",
matchIfMissing = true)
static class CglibAutoProxyConfiguration {
}
}
@Configuration(proxyBeanMethods = false)
@ConditionalOnMissingClass("org.aspectj.weaver.Advice")
@ConditionalOnProperty(prefix = "spring.aop", name = "proxy-target-class", havingValue = "true",
matchIfMissing = true)
static class ClassProxyingConfiguration {
ClassProxyingConfiguration(BeanFactory beanFactory) {
if (beanFactory instanceof BeanDefinitionRegistry) {
BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
AopConfigUtils.registerAutoProxyCreatorIfNecessary(registry);
AopConfigUtils.forceAutoProxyCreatorToUseClassProxying(registry);
}
}
}
}
META-INF/spring.factories文件： 下面包含org.springframework.boot.autoconfigure.aop.AopAutoConfiguration，AOP的加载类(组件)
# Initializers org.springframework.context.ApplicationContextInitializer= org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer, org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener # Application Listeners org.springframework.context.ApplicationListener= org.springframework.boot.autoconfigure.BackgroundPreinitializer # Environment Post Processors org.springframework.boot.env.EnvironmentPostProcessor= org.springframework.boot.autoconfigure.integration.IntegrationPropertiesEnvironmentPostProcessor # Auto Configuration Import Listeners org.springframework.boot.autoconfigure.AutoConfigurationImportListener= org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListener # Auto Configuration Import Filters org.springframework.boot.autoconfigure.AutoConfigurationImportFilter= org.springframework.boot.autoconfigure.condition.OnBeanCondition, org.springframework.boot.autoconfigure.condition.OnClassCondition, org.springframework.boot.autoconfigure.condition.OnWebApplicationCondition # Auto Configure org.springframework.boot.autoconfigure.EnableAutoConfiguration= org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration, org.springframework.boot.autoconfigure.aop.AopAutoConfiguration, org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration, org.springframework.boot.autoconfigure.batch.BatchAutoConfiguration, org.springframework.boot.autoconfigure.cache.CacheAutoConfiguration, org.springframework.boot.autoconfigure.cassandra.CassandraAutoConfiguration, org.springframework.boot.autoconfigure.context.ConfigurationPropertiesAutoConfiguration, org.springframework.boot.autoconfigure.context.LifecycleAutoConfiguration, org.springframework.boot.autoconfigure.context.MessageSourceAutoConfiguration, org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration, org.springframework.boot.autoconfigure.couchbase.CouchbaseAutoConfiguration, org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration, org.springframework.boot.autoconfigure.data.cassandra.CassandraDataAutoConfiguration, org.springframework.boot.autoconfigure.data.cassandra.CassandraReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.cassandra.CassandraReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.cassandra.CassandraRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.couchbase.CouchbaseDataAutoConfiguration, org.springframework.boot.autoconfigure.data.couchbase.CouchbaseReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.couchbase.CouchbaseReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.couchbase.CouchbaseRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchDataAutoConfiguration, org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.elasticsearch.ReactiveElasticsearchRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.elasticsearch.ReactiveElasticsearchRestClientAutoConfiguration, org.springframework.boot.autoconfigure.data.jdbc.JdbcRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.jpa.JpaRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.ldap.LdapRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration, org.springframework.boot.autoconfigure.data.mongo.MongoReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.mongo.MongoReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.mongo.MongoRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.r2dbc.R2dbcDataAutoConfiguration, org.springframework.boot.autoconfigure.data.r2dbc.R2dbcRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration, org.springframework.boot.autoconfigure.data.redis.RedisReactiveAutoConfiguration, org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.rest.RepositoryRestMvcAutoConfiguration, org.springframework.boot.autoconfigure.data.web.SpringDataWebAutoConfiguration, org.springframework.boot.autoconfigure.elasticsearch.ElasticsearchRestClientAutoConfiguration, org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration, org.springframework.boot.autoconfigure.freemarker.FreeMarkerAutoConfiguration, org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAutoConfiguration, org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration, org.springframework.boot.autoconfigure.h2.H2ConsoleAutoConfiguration, org.springframework.boot.autoconfigure.hateoas.HypermediaAutoConfiguration, org.springframework.boot.autoconfigure.hazelcast.HazelcastAutoConfiguration, org.springframework.boot.autoconfigure.hazelcast.HazelcastJpaDependencyAutoConfiguration, org.springframework.boot.autoconfigure.http.HttpMessageConvertersAutoConfiguration, org.springframework.boot.autoconfigure.http.codec.CodecsAutoConfiguration, org.springframework.boot.autoconfigure.influx.InfluxDbAutoConfiguration, org.springframework.boot.autoconfigure.info.ProjectInfoAutoConfiguration, org.springframework.boot.autoconfigure.integration.IntegrationAutoConfiguration, org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration, org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration, org.springframework.boot.autoconfigure.jdbc.JdbcTemplateAutoConfiguration, org.springframework.boot.autoconfigure.jdbc.JndiDataSourceAutoConfiguration, org.springframework.boot.autoconfigure.jdbc.XADataSourceAutoConfiguration, org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration, org.springframework.boot.autoconfigure.jms.JmsAutoConfiguration, org.springframework.boot.autoconfigure.jmx.JmxAutoConfiguration, org.springframework.boot.autoconfigure.jms.JndiConnectionFactoryAutoConfiguration, org.springframework.boot.autoconfigure.jms.activemq.ActiveMQAutoConfiguration, org.springframework.boot.autoconfigure.jms.artemis.ArtemisAutoConfiguration, org.springframework.boot.autoconfigure.jersey.JerseyAutoConfiguration, org.springframework.boot.autoconfigure.jooq.JooqAutoConfiguration, org.springframework.boot.autoconfigure.jsonb.JsonbAutoConfiguration, org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration, org.springframework.boot.autoconfigure.availability.ApplicationAvailabilityAutoConfiguration, org.springframework.boot.autoconfigure.ldap.embedded.EmbeddedLdapAutoConfiguration, org.springframework.boot.autoconfigure.ldap.LdapAutoConfiguration, org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration, org.springframework.boot.autoconfigure.mail.MailSenderAutoConfiguration, org.springframework.boot.autoconfigure.mail.MailSenderValidatorAutoConfiguration, org.springframework.boot.autoconfigure.mongo.embedded.EmbeddedMongoAutoConfiguration, org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration, org.springframework.boot.autoconfigure.mongo.MongoReactiveAutoConfiguration, org.springframework.boot.autoconfigure.mustache.MustacheAutoConfiguration, org.springframework.boot.autoconfigure.neo4j.Neo4jAutoConfiguration, org.springframework.boot.autoconfigure.netty.NettyAutoConfiguration, org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration, org.springframework.boot.autoconfigure.quartz.QuartzAutoConfiguration, org.springframework.boot.autoconfigure.r2dbc.R2dbcAutoConfiguration, org.springframework.boot.autoconfigure.r2dbc.R2dbcTransactionManagerAutoConfiguration, org.springframework.boot.autoconfigure.rsocket.RSocketMessagingAutoConfiguration, org.springframework.boot.autoconfigure.rsocket.RSocketRequesterAutoConfiguration, org.springframework.boot.autoconfigure.rsocket.RSocketServerAutoConfiguration, org.springframework.boot.autoconfigure.rsocket.RSocketStrategiesAutoConfiguration, org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration, org.springframework.boot.autoconfigure.security.servlet.UserDetailsServiceAutoConfiguration, org.springframework.boot.autoconfigure.security.servlet.SecurityFilterAutoConfiguration, org.springframework.boot.autoconfigure.security.reactive.ReactiveSecurityAutoConfiguration, org.springframework.boot.autoconfigure.security.reactive.ReactiveUserDetailsServiceAutoConfiguration, org.springframework.boot.autoconfigure.security.rsocket.RSocketSecurityAutoConfiguration, org.springframework.boot.autoconfigure.security.saml2.Saml2RelyingPartyAutoConfiguration, org.springframework.boot.autoconfigure.sendgrid.SendGridAutoConfiguration, org.springframework.boot.autoconfigure.session.SessionAutoConfiguration, org.springframework.boot.autoconfigure.security.oauth2.client.servlet.OAuth2ClientAutoConfiguration, org.springframework.boot.autoconfigure.security.oauth2.client.reactive.ReactiveOAuth2ClientAutoConfiguration, org.springframework.boot.autoconfigure.security.oauth2.resource.servlet.OAuth2ResourceServerAutoConfiguration, org.springframework.boot.autoconfigure.security.oauth2.resource.reactive.ReactiveOAuth2ResourceServerAutoConfiguration, org.springframework.boot.autoconfigure.solr.SolrAutoConfiguration, org.springframework.boot.autoconfigure.sql.init.SqlInitializationAutoConfiguration, org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration, org.springframework.boot.autoconfigure.task.TaskSchedulingAutoConfiguration, org.springframework.boot.autoconfigure.thymeleaf.ThymeleafAutoConfiguration, org.springframework.boot.autoconfigure.transaction.TransactionAutoConfiguration, org.springframework.boot.autoconfigure.transaction.jta.JtaAutoConfiguration, org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration, org.springframework.boot.autoconfigure.web.client.RestTemplateAutoConfiguration, org.springframework.boot.autoconfigure.web.embedded.EmbeddedWebServerFactoryCustomizerAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.HttpHandlerAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.ReactiveMultipartAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.ReactiveWebServerFactoryAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.WebSessionIdResolverAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.error.ErrorWebFluxAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.function.client.ClientHttpConnectorAutoConfiguration, org.springframework.boot.autoconfigure.web.reactive.function.client.WebClientAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.DispatcherServletAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.ServletWebServerFactoryAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.HttpEncodingAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.MultipartAutoConfiguration, org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration, org.springframework.boot.autoconfigure.websocket.reactive.WebSocketReactiveAutoConfiguration, org.springframework.boot.autoconfigure.websocket.servlet.WebSocketServletAutoConfiguration, org.springframework.boot.autoconfigure.websocket.servlet.WebSocketMessagingAutoConfiguration, org.springframework.boot.autoconfigure.webservices.WebServicesAutoConfiguration, org.springframework.boot.autoconfigure.webservices.client.WebServiceTemplateAutoConfiguration # Failure analyzers org.springframework.boot.diagnostics.FailureAnalyzer= org.springframework.boot.autoconfigure.data.redis.RedisUrlSyntaxFailureAnalyzer, org.springframework.boot.autoconfigure.diagnostics.analyzer.NoSuchBeanDefinitionFailureAnalyzer, org.springframework.boot.autoconfigure.flyway.FlywayMigrationScriptMissingFailureAnalyzer, org.springframework.boot.autoconfigure.jdbc.DataSourceBeanCreationFailureAnalyzer, org.springframework.boot.autoconfigure.jdbc.HikariDriverConfigurationFailureAnalyzer, org.springframework.boot.autoconfigure.jooq.NoDslContextBeanFailureAnalyzer, org.springframework.boot.autoconfigure.r2dbc.ConnectionFactoryBeanCreationFailureAnalyzer, org.springframework.boot.autoconfigure.r2dbc.MissingR2dbcPoolDependencyFailureAnalyzer, org.springframework.boot.autoconfigure.r2dbc.MultipleConnectionPoolConfigurationsFailureAnalzyer, org.springframework.boot.autoconfigure.r2dbc.NoConnectionFactoryBeanFailureAnalyzer, org.springframework.boot.autoconfigure.session.NonUniqueSessionRepositoryFailureAnalyzer # Template availability providers org.springframework.boot.autoconfigure.template.TemplateAvailabilityProvider= org.springframework.boot.autoconfigure.freemarker.FreeMarkerTemplateAvailabilityProvider, org.springframework.boot.autoconfigure.mustache.MustacheTemplateAvailabilityProvider, org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAvailabilityProvider, org.springframework.boot.autoconfigure.thymeleaf.ThymeleafTemplateAvailabilityProvider, org.springframework.boot.autoconfigure.web.servlet.JspTemplateAvailabilityProvider # DataSource initializer detectors org.springframework.boot.sql.init.dependency.DatabaseInitializerDetector= org.springframework.boot.autoconfigure.flyway.FlywayMigrationInitializerDatabaseInitializerDetector # Depends on database initialization detectors org.springframework.boot.sql.init.dependency.DependsOnDatabaseInitializationDetector= org.springframework.boot.autoconfigure.batch.JobRepositoryDependsOnDatabaseInitializationDetector, org.springframework.boot.autoconfigure.quartz.SchedulerDependsOnDatabaseInitializationDetector, org.springframework.boot.autoconfigure.session.JdbcIndexedSessionRepositoryDependsOnDatabaseInitializationDetector
3.流程分析(面试回答)
1.@SpringBootApplication标明启动主程序，可以使用exclude属性来排除需要进行自动装配的组件，使用scanBasePackages来指明需要扫描的包。
2.@SpringBootApplication --> @EnableAutoConfiguration -->@AutoConfigurationPackage进行自动包管理，加载应用内相关组件。
3.通过流程，AutoConfigurationImportSelector类的方法selectImports --> 方法getAutoConfigurationEntry --> 方法getCandidateConfigurations，再到SpringFactoriesLoader类的方法loadFactoryNames --> 方法loadSpringFactories
，再到文件META-INF/spring.factories来获取需要被加载的entry信息(组件)，然后根据组件的自动配置类中的ConditionalOnProperty注解来判断配置是否生效，按需加载
Spring Boot的自动装配原理借鉴了Java SPI机制，简单总结就是，自动管理，按需加载。