Spring 源码解析十四：SpringBoot Autoconfigure 初始化应用时加载的组件
这些组件定义在 spring.factories
中
# 初始化器
org.springframework.context.ApplicationContextInitializer=\
org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer,\
org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener
# 应用事件监听器
org.springframework.context.ApplicationListener=\
org.springframework.boot.autoconfigure.BackgroundPreinitializer
# 自动配置导入监听器
org.springframework.boot.autoconfigure.AutoConfigurationImportListener=\
org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListener
# 自动配置导入过滤器
org.springframework.boot.autoconfigure.AutoConfigurationImportFilter=\
org.springframework.boot.autoconfigure.condition.OnBeanCondition,\
org.springframework.boot.autoconfigure.condition.OnClassCondition,\
org.springframework.boot.autoconfigure.condition.OnWebApplicationCondition
# 自动配置
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.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.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.ReactiveWebServerFactoryAutoConfiguration,\
org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration,\
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
# 失败分析器
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.r2dbc.ConnectionFactoryBeanCreationFailureAnalyzer,\
org.springframework.boot.autoconfigure.session.NonUniqueSessionRepositoryFailureAnalyzer
# 检查模板可用提供器
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.JspTemplateAvailabilityProvider1. 初始化器
org.springframework.context.ApplicationContextInitializer=\
org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer,\
org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener1.1. SharedMetadataReaderFactoryContextInitializer
SharedMetadataReaderFactoryContextInitializer
的主要功能是提供一个共享的缓存元信息读取工厂
class SharedMetadataReaderFactoryContextInitializer
implements ApplicationContextInitializer<ConfigurableApplicationContext>, Ordered {
// 初始化
@Override
public void initialize(ConfigurableApplicationContext applicationContext) {
BeanFactoryPostProcessor postProcessor = new CachingMetadataReaderFactoryPostProcessor(applicationContext);
applicationContext.addBeanFactoryPostProcessor(postProcessor);
}
static class CachingMetadataReaderFactoryPostProcessor
implements BeanDefinitionRegistryPostProcessor, PriorityOrdered {
// 注册bean定义
@Override
public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
// 注册bean定义注册器
register(registry);
// 配置 @Configuration bean
configureConfigurationClassPostProcessor(registry);
}
// 注册bean定义注册器
private void register(BeanDefinitionRegistry registry) {
BeanDefinition definition = BeanDefinitionBuilder
.genericBeanDefinition(SharedMetadataReaderFactoryBean.class, SharedMetadataReaderFactoryBean::new)
.getBeanDefinition();
// 注册为 "org.springframework.boot.autoconfigure.internalCachingMetadataReaderFactory" 名字
registry.registerBeanDefinition(BEAN_NAME, definition);
}
// 配置 @Configuration bean
private void configureConfigurationClassPostProcessor(BeanDefinitionRegistry registry) {
try {
// 配置bean "org.springframework.context.annotation.internalConfigurationAnnotationProcessor"
configureConfigurationClassPostProcessor(
registry.getBeanDefinition(AnnotationConfigUtils.CONFIGURATION_ANNOTATION_PROCESSOR_BEAN_NAME));
}
catch (NoSuchBeanDefinitionException ex) {
}
}
}
}1.2. ConditionEvaluationReportLoggingListener
ConditionEvaluationReportLoggingListener
的主要功能是输出日志到文件
2. 应用事件监听器
org.springframework.context.ApplicationListener=\
org.springframework.boot.autoconfigure.BackgroundPreinitializerBackgroundPreinitializer
的主要功能是初始化数据转换与编码等服务
public class BackgroundPreinitializer implements ApplicationListener<SpringApplicationEvent> {
@Override
public void onApplicationEvent(SpringApplicationEvent event) {
// ... 代码省略
if (event instanceof ApplicationEnvironmentPreparedEvent
&& preinitializationStarted.compareAndSet(false, true)) {
performPreinitialization();
}
if ((event instanceof ApplicationReadyEvent || event instanceof ApplicationFailedEvent)
&& preinitializationStarted.get()) {
try {
preinitializationComplete.await();
}
catch (InterruptedException ex) {
Thread.currentThread().interrupt();
}
}
}
// 初始化其他组件
private void performPreinitialization() {
try {
Thread thread = new Thread(new Runnable() {
@Override
public void run() {
// 初始化数据转换服务，DefaultFormattingConversionService
runSafely(new ConversionServiceInitializer());
// 初始化数据验证服务，Validation.byDefaultProvider()
runSafely(new ValidationInitializer());
// 初始化消息转换服务，AllEncompassingFormHttpMessageConverter
runSafely(new MessageConverterInitializer());
// 初始化JSON服务，Jackson2ObjectMapperBuilder
runSafely(new JacksonInitializer());
// 初始化字符编码服务，StandardCharsets
runSafely(new CharsetInitializer());
preinitializationComplete.countDown();
}
public void runSafely(Runnable runnable) {
try {
runnable.run();
}
catch (Throwable ex) {}
}
}, "background-preinit");
thread.start();
}
catch (Exception ex) {
// ... 代码省略
}
}
private static class MessageConverterInitializer implements Runnable {
@Override
public void run() {
new AllEncompassingFormHttpMessageConverter();
}
}
private static class ValidationInitializer implements Runnable {
@Override
public void run() {
Configuration<?> configuration = Validation.byDefaultProvider().configure();
configuration.buildValidatorFactory().getValidator();
}
}
private static class JacksonInitializer implements Runnable {
@Override
public void run() {
Jackson2ObjectMapperBuilder.json().build();
}
}
private static class ConversionServiceInitializer implements Runnable {
@Override
public void run() {
new DefaultFormattingConversionService();
}
}
private static class CharsetInitializer implements Runnable {
@Override
public void run() {
StandardCharsets.UTF_8.name();
}
}
}3. 自动配置导入监听器
org.springframework.boot.autoconfigure.AutoConfigurationImportListener=\
org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListenerConditionEvaluationReportAutoConfigurationImportListener
的主要功能是从 Report 中读取结果
4. 自动配置导入过滤器
org.springframework.boot.autoconfigure.AutoConfigurationImportFilter=\
org.springframework.boot.autoconfigure.condition.OnBeanCondition,\
org.springframework.boot.autoconfigure.condition.OnClassCondition,\
org.springframework.boot.autoconfigure.condition.OnWebApplicationCondition4.1. OnBeanCondition
OnBeanCondition
的主要功能是处理注解 @ConditionalOnBean、@ConditionalOnMissingBean、@ConditionalOnSingleCandidate，按条件动态载入 bean
@ConditionOnBean判断条件 bean 存在，注入当下注解的 bean@ConditionOnMissingBean判断条件 bean 不存在，才注入当下注解的 bean@ConditionalOnSingleCandidate判断条件 bean 只能有一个实例或多个但只有一个 primary 实例，才注入当下注解的 bean
先来看看继承关系
- SpringBootCondition
- FilteringSpringBootCondition
- OnBeanCondition4.1.1. SpringBootCondition
SpringBootCondition
是用条件来检查组件的基础类
public abstract class SpringBootCondition implements Condition {
// 元信息代表的组件是否匹配
@Override
public final boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
// 获取类名或方法名
String classOrMethodName = getClassOrMethodName(metadata);
try {
// 获取匹配结果
ConditionOutcome outcome = getMatchOutcome(context, metadata);
// ... 代码省略
// 返回是否匹配
return outcome.isMatch();
}
catch (NoClassDefFoundError ex) {
// ... 代码省略
}
// ... 代码省略
}
// 获取匹配结果，由子类实现
public abstract ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata);
}4.1.2. FilteringSpringBootCondition
FilteringSpringBootCondition
的主要功能是添加过滤功能
abstract class FilteringSpringBootCondition extends SpringBootCondition
implements AutoConfigurationImportFilter, BeanFactoryAware, BeanClassLoaderAware {
// 元信息代表的组件是否匹配
@Override
public boolean[] match(String[] autoConfigurationClasses, AutoConfigurationMetadata autoConfigurationMetadata) {
// 获取结果
ConditionOutcome[] outcomes = getOutcomes(autoConfigurationClasses, autoConfigurationMetadata);
boolean[] match = new boolean[outcomes.length];
for (int i = 0; i < outcomes.length; i++) {
// 如果返回为null或true，则表示匹配
match[i] = (outcomes[i] == null || outcomes[i].isMatch());
// ... 代码省略
}
return match;
}
// 获取结果，由子类实现
protected abstract ConditionOutcome[] getOutcomes(String[] autoConfigurationClasses,
AutoConfigurationMetadata autoConfigurationMetadata);
}4.1.3. SpringBootCondition
SpringBootCondition
的主要功能是处理注解 @ConditionalOnBean、@ConditionalOnMissingBean、@ConditionalOnSingleCandidate，按条件动态载入 bean
class OnBeanCondition extends FilteringSpringBootCondition implements ConfigurationCondition {
// 获取结果
@Override
protected final ConditionOutcome[] getOutcomes(String[] autoConfigurationClasses,
AutoConfigurationMetadata autoConfigurationMetadata) {
// 结果集
ConditionOutcome[] outcomes = new ConditionOutcome[autoConfigurationClasses.length];
for (int i = 0; i < outcomes.length; i++) {
// 自动配置类
String autoConfigurationClass = autoConfigurationClasses[i];
if (autoConfigurationClass != null) {
// 获取ConditionalOnBean的bean类型
Set<String> onBeanTypes = autoConfigurationMetadata.getSet(autoConfigurationClass, "ConditionalOnBean");
// 确定有没有ConditionalOnBean的bean类型
outcomes[i] = getOutcome(onBeanTypes, ConditionalOnBean.class);
if (outcomes[i] == null) {
// 获取ConditionalOnSingleCandidate的bean类型
Set<String> onSingleCandidateTypes = autoConfigurationMetadata.getSet(autoConfigurationClass,
"ConditionalOnSingleCandidate");
// 确定有没有ConditionalOnSingleCandidate的bean类型
outcomes[i] = getOutcome(onSingleCandidateTypes, ConditionalOnSingleCandidate.class);
}
}
}
return outcomes;
}
}class OnBeanCondition extends FilteringSpringBootCondition implements ConfigurationCondition {
// 获取匹配结果
@Override
public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
// 匹配信息
ConditionMessage matchMessage = ConditionMessage.empty();
// 元信息中的注解
MergedAnnotations annotations = metadata.getAnnotations();
// 有@ConditionalOnBean注解
if (annotations.isPresent(ConditionalOnBean.class)) {
// 创建ConditionalOnBean的匹配标准对象
Spec<ConditionalOnBean> spec = new Spec<>(context, metadata, annotations, ConditionalOnBean.class);
// 获取匹配的bean
MatchResult matchResult = getMatchingBeans(context, spec);
// 如果一个都没有匹配到
if (!matchResult.isAllMatched()) {
// 返回匹配不到的信息
String reason = createOnBeanNoMatchReason(matchResult);
return ConditionOutcome.noMatch(spec.message().because(reason));
}
// 匹配到了，继续
matchMessage = spec.message(matchMessage).found("bean", "beans").items(Style.QUOTE,
matchResult.getNamesOfAllMatches());
}
// 有@ConditionalOnSingleCandidate注解
if (metadata.isAnnotated(ConditionalOnSingleCandidate.class.getName())) {
// 创建ConditionalOnSingleCandidate的匹配标准对象
Spec<ConditionalOnSingleCandidate> spec = new SingleCandidateSpec(context, metadata, annotations);
// 获取匹配的bean
MatchResult matchResult = getMatchingBeans(context, spec);
// 如果一个都没有匹配到
if (!matchResult.isAllMatched()) {
// 返回匹配不到的信息
return ConditionOutcome.noMatch(spec.message().didNotFind("any beans").atAll());
}
// 匹配到多个bean，但没有primary bean
else if (!hasSingleAutowireCandidate(context.getBeanFactory(), matchResult.getNamesOfAllMatches(),
spec.getStrategy() == SearchStrategy.ALL)) {
// 返回匹配到多个的信息
return ConditionOutcome.noMatch(spec.message().didNotFind("a primary bean from beans")
.items(Style.QUOTE, matchResult.getNamesOfAllMatches()));
}
// 匹配到了，继续
matchMessage = spec.message(matchMessage).found("a primary bean from beans").items(Style.QUOTE,
matchResult.getNamesOfAllMatches());
}
// 有@ConditionalOnMissingBean注解
if (metadata.isAnnotated(ConditionalOnMissingBean.class.getName())) {
// 创建ConditionalOnMissingBean的匹配标准对象
Spec<ConditionalOnMissingBean> spec = new Spec<>(context, metadata, annotations,
ConditionalOnMissingBean.class);
// 获取匹配的bean
MatchResult matchResult = getMatchingBeans(context, spec);
// 如果匹配到了
if (matchResult.isAnyMatched()) {
// 返回匹配到了的信息
String reason = createOnMissingBeanNoMatchReason(matchResult);
return ConditionOutcome.noMatch(spec.message().because(reason));
}
// 匹配不到，继续
matchMessage = spec.message(matchMessage).didNotFind("any beans").atAll();
}
return ConditionOutcome.match(matchMessage);
}
}4.2. OnClassCondition
OnClassCondition
的主要功能是处理注解 @ConditionalOnClass、@ConditionalOnMissingClass，按条件动态载入 bean
@ConditionalOnClass判断条件类存在，注入当下注解的 bean@ConditionalOnMissingClass判断条件类不存在，才注入当下注解的 bean
class OnClassCondition extends FilteringSpringBootCondition {
// 获取结果
@Override
protected final ConditionOutcome[] getOutcomes(String[] autoConfigurationClasses,
AutoConfigurationMetadata autoConfigurationMetadata) {
// ... 代码省略
OutcomesResolver outcomesResolver = new StandardOutcomesResolver(autoConfigurationClasses, 0,
autoConfigurationClasses.length, autoConfigurationMetadata, getBeanClassLoader());
// 获取ConditionalOnClass的输出
return outcomesResolver.resolveOutcomes();
}
// 获取匹配结果
@Override
public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
ClassLoader classLoader = context.getClassLoader();
// 匹配信息
ConditionMessage matchMessage = ConditionMessage.empty();
// 获取标记有@ConditionalOnClass注解的类
List<String> onClasses = getCandidates(metadata, ConditionalOnClass.class);
if (onClasses != null) {
List<String> missing = filter(onClasses, ClassNameFilter.MISSING, classLoader);
// 类不存在，返回
if (!missing.isEmpty()) {
return ConditionOutcome.noMatch(ConditionMessage.forCondition(ConditionalOnClass.class)
.didNotFind("required class", "required classes").items(Style.QUOTE, missing));
}
// 类存在，继续
matchMessage = matchMessage.andCondition(ConditionalOnClass.class)
.found("required class", "required classes")
.items(Style.QUOTE, filter(onClasses, ClassNameFilter.PRESENT, classLoader));
}
// 获取标记有@ConditionalOnMissingClass注解的类
List<String> onMissingClasses = getCandidates(metadata, ConditionalOnMissingClass.class);
if (onMissingClasses != null) {
List<String> present = filter(onMissingClasses, ClassNameFilter.PRESENT, classLoader);
// 类存在，返回
if (!present.isEmpty()) {
return ConditionOutcome.noMatch(ConditionMessage.forCondition(ConditionalOnMissingClass.class)
.found("unwanted class", "unwanted classes").items(Style.QUOTE, present));
}
// 类不存在，继续
matchMessage = matchMessage.andCondition(ConditionalOnMissingClass.class)
.didNotFind("unwanted class", "unwanted classes")
.items(Style.QUOTE, filter(onMissingClasses, ClassNameFilter.MISSING, classLoader));
}
return ConditionOutcome.match(matchMessage);
}
}4.3. OnWebApplicationCondition
OnWebApplicationCondition
的主要功能是处理注解 @ConditionalOnWebApplication、@ConditionalOnNotWebApplication，按条件动态载入 bean
@ConditionalOnWebApplication判断应用时 Web 应用时，注入当下注解的 bean@ConditionalOnNotWebApplication判断应用时不是 Web 应用时，才注入当下注解的 bean
5. 自动配置
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.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.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.ReactiveWebServerFactoryAutoConfiguration,\
org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration,\
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- SpringApplicationAdminJmxAutoConfiguration
- AopAutoConfiguration
- RabbitAutoConfiguration
- BatchAutoConfiguration
- CacheAutoConfiguration
- CassandraAutoConfiguration
- ConfigurationPropertiesAutoConfiguration
- LifecycleAutoConfiguration
- MessageSourceAutoConfiguration
- PropertyPlaceholderAutoConfiguration
- CouchbaseAutoConfiguration
- PersistenceExceptionTranslationAutoConfiguration
- CassandraDataAutoConfiguration
- CassandraReactiveDataAutoConfiguration
- CassandraReactiveRepositoriesAutoConfiguration
- CassandraRepositoriesAutoConfiguration
- CouchbaseDataAutoConfiguration
- CouchbaseReactiveDataAutoConfiguration
- CouchbaseReactiveRepositoriesAutoConfiguration
- CouchbaseRepositoriesAutoConfiguration
- ElasticsearchDataAutoConfiguration
- ElasticsearchRepositoriesAutoConfiguration
- ReactiveElasticsearchRepositoriesAutoConfiguration
- ReactiveElasticsearchRestClientAutoConfiguration
- JdbcRepositoriesAutoConfiguration
- JpaRepositoriesAutoConfiguration
- LdapRepositoriesAutoConfiguration
- MongoDataAutoConfiguration
- MongoReactiveDataAutoConfiguration
- MongoReactiveRepositoriesAutoConfiguration
- MongoRepositoriesAutoConfiguration
- Neo4jDataAutoConfiguration
- Neo4jReactiveDataAutoConfiguration
- Neo4jReactiveRepositoriesAutoConfiguration
- Neo4jRepositoriesAutoConfiguration
- R2dbcDataAutoConfiguration
- R2dbcRepositoriesAutoConfiguration
- RedisAutoConfiguration
- RedisReactiveAutoConfiguration
- RedisRepositoriesAutoConfiguration
- RepositoryRestMvcAutoConfiguration
- SpringDataWebAutoConfiguration
- ElasticsearchRestClientAutoConfiguration
- FlywayAutoConfiguration
- FreeMarkerAutoConfiguration
- GroovyTemplateAutoConfiguration
- GsonAutoConfiguration
- H2ConsoleAutoConfiguration
- HypermediaAutoConfiguration
- HazelcastAutoConfiguration
- HazelcastJpaDependencyAutoConfiguration
- HttpMessageConvertersAutoConfiguration
- CodecsAutoConfiguration
- InfluxDbAutoConfiguration
- ProjectInfoAutoConfiguration
- IntegrationAutoConfiguration
- JacksonAutoConfiguration
- DataSourceAutoConfiguration
- JdbcTemplateAutoConfiguration
- JndiDataSourceAutoConfiguration
- XADataSourceAutoConfiguration
- DataSourceTransactionManagerAutoConfiguration
- JmsAutoConfiguration
- JmxAutoConfiguration
- JndiConnectionFactoryAutoConfiguration
- ActiveMQAutoConfiguration
- ArtemisAutoConfiguration
- JerseyAutoConfiguration
- JooqAutoConfiguration
- JsonbAutoConfiguration
- KafkaAutoConfiguration
- ApplicationAvailabilityAutoConfiguration
- EmbeddedLdapAutoConfiguration
- LdapAutoConfiguration
- LiquibaseAutoConfiguration
- MailSenderAutoConfiguration
- MailSenderValidatorAutoConfiguration
- EmbeddedMongoAutoConfiguration
- MongoAutoConfiguration
- MongoReactiveAutoConfiguration
- MustacheAutoConfiguration
- Neo4jAutoConfiguration
- HibernateJpaAutoConfiguration
- QuartzAutoConfiguration
- R2dbcAutoConfiguration
- R2dbcTransactionManagerAutoConfiguration
- RSocketMessagingAutoConfiguration
- RSocketRequesterAutoConfiguration
- RSocketServerAutoConfiguration
- RSocketStrategiesAutoConfiguration
- SecurityAutoConfiguration
- UserDetailsServiceAutoConfiguration
- SecurityFilterAutoConfiguration
- ReactiveSecurityAutoConfiguration
- ReactiveUserDetailsServiceAutoConfiguration
- RSocketSecurityAutoConfiguration
- Saml2RelyingPartyAutoConfiguration
- SendGridAutoConfiguration
- SessionAutoConfiguration
- OAuth2ClientAutoConfiguration
- ReactiveOAuth2ClientAutoConfiguration
- OAuth2ResourceServerAutoConfiguration
- ReactiveOAuth2ResourceServerAutoConfiguration
- SolrAutoConfiguration
- TaskExecutionAutoConfiguration
- TaskSchedulingAutoConfiguration
- ThymeleafAutoConfiguration
- TransactionAutoConfiguration
- JtaAutoConfiguration
- ValidationAutoConfiguration
- RestTemplateAutoConfiguration
- EmbeddedWebServerFactoryCustomizerAutoConfiguration
- HttpHandlerAutoConfiguration
- ReactiveWebServerFactoryAutoConfiguration
- WebFluxAutoConfiguration
- ErrorWebFluxAutoConfiguration
- ClientHttpConnectorAutoConfiguration
- WebClientAutoConfiguration
- DispatcherServletAutoConfiguration
- ServletWebServerFactoryAutoConfiguration
- ErrorMvcAutoConfiguration
- HttpEncodingAutoConfiguration
- MultipartAutoConfiguration
- WebMvcAutoConfiguration
- WebSocketReactiveAutoConfiguration
- WebSocketServletAutoConfiguration
- WebSocketMessagingAutoConfiguration
- WebServicesAutoConfiguration
- WebServiceTemplateAutoConfiguration
以上的类都是通过 application*.yaml 中的属性配置自动装载成 bean。这些类比较多，可以自行探索
6. 失败分析器
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.r2dbc.ConnectionFactoryBeanCreationFailureAnalyzer,\
org.springframework.boot.autoconfigure.session.NonUniqueSessionRepositoryFailureAnalyzer- RedisUrlSyntaxFailureAnalyzer
Redis url 语法错误 - NoSuchBeanDefinitionFailureAnalyzer
没有 bean 定义 - FlywayMigrationScriptMissingFailureAnalyzer
Flyway 没有可用的 sql 脚本 - DataSourceBeanCreationFailureAnalyzer
数据库源 bean 创建失败 - HikariDriverConfigurationFailureAnalyzer
HikariCP 配置失败 - ConnectionFactoryBeanCreationFailureAnalyzer
ConnectionFactory bean 创建失败 - NonUniqueSessionRepositoryFailureAnalyzer
多个 Spring Session 错误
这些类都比较简单，可以自行探索
7. 检查模板可用提供器
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- FreeMarkerTemplateAvailabilityProvider
FreeMarker 模板检查 - MustacheTemplateAvailabilityProvider
Mustache 模板检查 - GroovyTemplateAvailabilityProvider
Groovy 模板检查 - ThymeleafTemplateAvailabilityProvider
Thymeleaf 模板检查 - JspTemplateAvailabilityProvider
Jsp 模板检查
这些类都比较简单，可以自行探索
后续
更多博客，查看 https://github.com/senntyou/blogs
版权声明：自由转载-非商用-非衍生-保持署名（创意共享 3.0 许可证）
java
**粗体** _斜体_ [链接](http://example.com) `代码` - 列表 > 引用。你还可以使用@来通知其他用户。