Spring Boot启动流程概述

 

1、创建SpringApplication实例：

 

  public SpringApplication(ResourceLoader resourceLoader, Class... primarySources) {

        this.sources = new LinkedHashSet();

        this.bannerMode = Mode.CONSOLE;

        this.logStartupInfo = true;

        this.addCommandLineProperties = true;

        this.headless = true;

        this.registerShutdownHook = true;

        this.additionalProfiles = new HashSet();

        this.resourceLoader = resourceLoader;

        Assert.notNull(primarySources, "PrimarySources must not be null");

        this.primarySources = new LinkedHashSet(Arrays.asList(primarySources));

        this.webApplicationType = this.deduceWebApplicationType();

        this.setInitializers(this.getSpringFactoriesInstances(ApplicationContextInitializer.class));

        this.setListeners(this.getSpringFactoriesInstances(ApplicationListener.class));

        this.mainApplicationClass = this.deduceMainApplicationClass();

    }

/META-INF/spring.factories  文件 

 

# PropertySource Loaders

org.springframework.boot.env.PropertySourceLoader=\

org.springframework.boot.env.PropertiesPropertySourceLoader,\

org.springframework.boot.env.YamlPropertySourceLoader

 

# Run Listeners

org.springframework.boot.SpringApplicationRunListener=\

org.springframework.boot.context.event.EventPublishingRunListener

 

# Error Reporters

org.springframework.boot.SpringBootExceptionReporter=\

org.springframework.boot.diagnostics.FailureAnalyzers

 

# Application Context Initializers

org.springframework.context.ApplicationContextInitializer=\

org.springframework.boot.context.ConfigurationWarningsApplicationContextInitializer,\

org.springframework.boot.context.ContextIdApplicationContextInitializer,\

org.springframework.boot.context.config.DelegatingApplicationContextInitializer,\

org.springframework.boot.web.context.ServerPortInfoApplicationContextInitializer

 

# Application Listeners

org.springframework.context.ApplicationListener=\

org.springframework.boot.ClearCachesApplicationListener,\

org.springframework.boot.builder.ParentContextCloserApplicationListener,\

org.springframework.boot.context.FileEncodingApplicationListener,\

org.springframework.boot.context.config.AnsiOutputApplicationListener,\

org.springframework.boot.context.config.ConfigFileApplicationListener,\

org.springframework.boot.context.config.DelegatingApplicationListener,\

org.springframework.boot.context.logging.ClasspathLoggingApplicationListener,\

org.springframework.boot.context.logging.LoggingApplicationListener,\

org.springframework.boot.liquibase.LiquibaseServiceLocatorApplicationListener

 

# Environment Post Processors

org.springframework.boot.env.EnvironmentPostProcessor=\

org.springframework.boot.cloud.CloudFoundryVcapEnvironmentPostProcessor,\

org.springframework.boot.env.SpringApplicationJsonEnvironmentPostProcessor,\

org.springframework.boot.env.SystemEnvironmentPropertySourceEnvironmentPostProcessor

 

# Failure Analyzers

org.springframework.boot.diagnostics.FailureAnalyzer=\

org.springframework.boot.diagnostics.analyzer.BeanCurrentlyInCreationFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.BeanNotOfRequiredTypeFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.BindFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.BindValidationFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.UnboundConfigurationPropertyFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.ConnectorStartFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.NoUniqueBeanDefinitionFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.PortInUseFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.ValidationExceptionFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.InvalidConfigurationPropertyNameFailureAnalyzer,\

org.springframework.boot.diagnostics.analyzer.InvalidConfigurationPropertyValueFailureAnalyzer

 

# FailureAnalysisReporters

org.springframework.boot.diagnostics.FailureAnalysisReporter=\

org.springframework.boot.diagnostics.LoggingFailureAnalysisReporter

将传入的启动类"com.example.ms.DemoApplication"放入Set集合中

判断是否为Web环境：存在（javax.servlet.Servlet && org.springframework.web.context.ConfigurableWebApplicationContext ）类则是

创建并初始化ApplicationInitializer列表 （spring.factories）

创建并初始化ApplicationListener列表  （spring.factories）

初始化主类mainApplicatioClass    (DemoApplication)

2、启动run方法

 

public ConfigurableApplicationContext run(String... args) {

        StopWatch stopWatch = new StopWatch();

        stopWatch.start();

        ConfigurableApplicationContext context = null;

        Collection<SpringBootExceptionReporter> exceptionReporters = new ArrayList();

        this.configureHeadlessProperty();

        SpringApplicationRunListeners listeners = this.getRunListeners(args);

        listeners.starting();

 

        Collection exceptionReporters;

        try {

            ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);

            ConfigurableEnvironment environment = this.prepareEnvironment(listeners, applicationArguments);

            this.configureIgnoreBeanInfo(environment);

            Banner printedBanner = this.printBanner(environment);

            context = this.createApplicationContext();

            exceptionReporters = this.getSpringFactoriesInstances(SpringBootExceptionReporter.class, new Class[]{ConfigurableApplicationContext.class}, context);

            this.prepareContext(context, environment, listeners, applicationArguments, printedBanner);

            this.refreshContext(context);

            this.afterRefresh(context, applicationArguments);

            stopWatch.stop();

            if (this.logStartupInfo) {

                (new StartupInfoLogger(this.mainApplicationClass)).logStarted(this.getApplicationLog(), stopWatch);

            }

 

            listeners.started(context);

            this.callRunners(context, applicationArguments);

        } catch (Throwable var10) {

            this.handleRunFailure(context, var10, exceptionReporters, listeners);

            throw new IllegalStateException(var10);

        }

 

        try {

            listeners.running(context);

            return context;

        } catch (Throwable var9) {

            this.handleRunFailure(context, var9, exceptionReporters, (SpringApplicationRunListeners)null);

            throw new IllegalStateException(var9);

        }

    }

创建计时器StopWatch

配置awt系统属性

获取SpringApplicationRunListeners

启动SpringApplicationRunListeners

创建ApplicationArguments

创建并初始化ConfigurableEnvironment

打印Banner

创建ConfigurableApplicationContext

准备ConfigurableApplicationContext

刷新ConfigurableApplicationContext

容器刷新后动作

SpringApplicationRunListeners发布finish事件

计时器停止计时

 

Spring Boot启动流程详解