PropertySource和Enviroment   http://blog.csdn.net/u011179993/article/details/51511364
    统一抽象资源---Resource  http://blog.csdn.net/u011179993/article/details/51531140
    SpringApplicationRunListener及其周期  http://blog.csdn.net/u011179993/article/details/51555690
    BeanDefinition及读取、注册  http://blog.csdn.net/u011179993/article/details/51598567
    http://blog.csdn.net/u011179993/article/category/5623745
    
    
    
BeanDefinitionRegistry   该类的作用主要是向注册表中注册 BeanDefinition 实例，完成 注册的过程。
        public interface BeanDefinitionRegistry extends AliasRegistry {
     
        // 关键 -> 往注册表中注册一个新的 BeanDefinition 实例 
        void registerBeanDefinition(String beanName, BeanDefinition beanDefinition)throws BeanDefinitionStoreException;
     
        // 移除注册表中已注册的 BeanDefinition 实例
        void removeBeanDefinition(String beanName) throws NoSuchBeanDefinitionException;
     
        // 从注册中取得指定的 BeanDefinition 实例
        BeanDefinition getBeanDefinition(String beanName) throws NoSuchBeanDefinitionException;
     
        // 判断 BeanDefinition 实例是否在注册表中（是否注册）
        boolean containsBeanDefinition(String beanName);
     
        // 取得注册表中所有 BeanDefinition 实例的 beanName（标识）
        String[] getBeanDefinitionNames();
     
        // 返回注册表中 BeanDefinition 实例的数量
        int getBeanDefinitionCount();
     
        // beanName（标识）是否被占用
        boolean isBeanNameInUse(String beanName);
        }
    
http://blog.csdn.net/u011179993/article/details/51655057	
BeanFactoryPostProcessor  当spring初始化好BenaDefinnitionMap之后，提供了一个接口BeanFactoryPostProcessor，允许我们开发者自定义的去修改BeanFactory中的内容，这也是符合“spring”的开闭原则
        public interface BeanFactoryPostProcessor {

    /**
     * 这里提供了修改beanFacotry的机会
         */
    void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException;

        }
    
http://jinnianshilongnian.iteye.com/blog/2000183
PropertySource：属性源，key-value属性对抽象，比如用于配置数据




PropertyResolver 属性解析器，用来根据名字解析其值等
    public interface PropertyResolver {  
      
        //是否包含某个属性  
        boolean containsProperty(String key);  
       
            //获取属性值 如果找不到返回null   
        String getProperty(String key);  
           
            //获取属性值，如果找不到返回默认值        
        String getProperty(String key, String defaultValue);  
        
            //获取指定类型的属性值，找不到返回null  
        <T> T getProperty(String key, Class<T> targetType);  
      
            //获取指定类型的属性值，找不到返回默认值  
        <T> T getProperty(String key, Class<T> targetType, T defaultValue);  
      
             //获取属性值为某个Class类型，找不到返回null，如果类型不兼容将抛出ConversionException  
        <T> Class<T> getPropertyAsClass(String key, Class<T> targetType);  
      
            //获取属性值，找不到抛出异常IllegalStateException  
        String getRequiredProperty(String key) throws IllegalStateException;  
      
            //获取指定类型的属性值，找不到抛出异常IllegalStateException         
        <T> T getRequiredProperty(String key, Class<T> targetType) throws IllegalStateException;  
      
            //替换文本中的占位符（${key}）到属性值，找不到不解析  
        String resolvePlaceholders(String text);  
      
            //替换文本中的占位符（${key}）到属性值，找不到抛出异常IllegalArgumentException  
        String resolveRequiredPlaceholders(String text) throws IllegalArgumentException;  
      
    }  	
    
http://blog.csdn.net/u011179993/article/details/51598567
BeanDefinition  这个接口描述bean的结构，对应XML中的< bean >或者配置类中的@Bean 它集成了BeanMetadataElement和AttributeAccessor
    
PropertyValues  包含了一个或者多个PropertyValue对象，通常用作特定的一个目的bean的属性更新	
    
AttributeAccessor接口定义了最基本的对任意对象的元数据的修改或者获取	
    
    
    
    
    private void initialize(Object[] sources) {
        if (sources != null && sources.length > 0) {
            this.sources.addAll(Arrays.asList(sources));
        }
        
        //判断是否web环境 
        //javax.servlet.Servlet"和"org.springframework.web.context.ConfigurableWebApplicationContext"类能被加载到代表为web环境
        this.webEnvironment = deduceWebEnvironment();
        
        
        /*
        *通过Thread.currentThread().getContextClassLoader(); 获取到 类加载器
        *获取 spring-boot-{v}.jar/META-INF/spring.factories 文件中 org.springframework.context.ApplicationContextInitializer 的值
        *   org.springframework.boot.context.ConfigurationWarningsApplicationContextInitializer   配置警告应用程序上下文初始化程序
        *   org.springframework.boot.context.ContextIdApplicationContextInitializer  上下文Id 应用上下文初始化器
        *   org.springframework.boot.context.config.DelegatingApplicationContextInitializer 委托应用程序上下文初始化程序
    *   org.springframework.boot.context.embedded.ServerPortInfoApplicationContextInitializer  设置端口
        *并通过各自的构造方法实例化
        *
        */
        setInitializers((Collection) getSpringFactoriesInstances(ApplicationContextInitializer.class));
      
      
      /*
      *获取 spring-boot-{v}.jar/META-INF/spring.factories 文件中 org.springframework.context.ApplicationListener 的值，并实例化
      *  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.liquibase.LiquibaseServiceLocatorApplicationListener
      *  org.springframework.boot.logging.ClasspathLoggingApplicationListener
      *  org.springframework.boot.logging.LoggingApplicationListener
      *
        setListeners((Collection) getSpringFactoriesInstances(ApplicationListener.class));
        
        
        
        /*
        *获取main方法所在的类
        *StackTraceElement[] stackTrace = new RuntimeException().getStackTrace(); 获取 虚拟机栈中 栈桢数组
        */
        this.mainApplicationClass = deduceMainApplicationClass();
    }


public ConfigurableApplicationContext run(String... args) {
        //计时器
        StopWatch stopWatch = new StopWatch();
        //开始计时
        stopWatch.start();
        ConfigurableApplicationContext context = null;
        FailureAnalyzers analyzers = null;
        
        //用来设置java.awt.headless 属性是true 还是false，是J2SE的一种模式用于在缺少显示屏、键盘    
    //或者鼠标时的系统配置
        configureHeadlessProperty();
        
        
        /*
        *获得运行侦听器  获取 spring-boot-{v}.jar/META-INF/spring.factories 文件中 org.springframework.boot.SpringApplicationRunListener 的值
        *  org.springframework.boot.context.event.EventPublishingRunListener 事件发布运行侦听器
        *在EventPublishingRunListener实例化时将 ApplicationListener的所有实现类添加 到SimpleApplicationEventMulticaster 事件中
        */
        SpringApplicationRunListeners listeners = getRunListeners(args);
        
        
        /*
        *启动SpringApplicationRunListeners侦听器
        *启动EventPublishingRunListener侦听器
        *org.springframework.boot.context.config.ConfigFileApplicationListener   onApplicationEvent没有做任何事
        *org.springframework.boot.logging.LoggingApplicationListener		onApplicationEvent加载 LoggingSystem对象
        *org.springframework.boot.context.config.DelegatingApplicationListener   onApplicationEvent没有做任何事
        *org.springframework.boot.liquibase.LiquibaseServiceLocatorApplicationListener  onApplicationEvent没有做任何事
        *调用以上监听器的onApplicationEvent 方法 
        */
        listeners.starting();
        
        
        try {
        
            //设置应用参数
            ApplicationArguments applicationArguments = new DefaultApplicationArguments(
                    args);
                    
            //加载配置
            ConfigurableEnvironment environment = prepareEnvironment(listeners,
                    applicationArguments);
                    
          //打印Banner  默认 SpringBootBanner.BANNER
            Banner printedBanner = printBanner(environment);
            
            //获取 上下文ApplicationContext
            context = createApplicationContext();
            //错误处理
            analyzers = new FailureAnalyzers(context);
            //准备上下文
            prepareContext(context, environment, listeners, applicationArguments,
                    printedBanner);
            //刷新上下文
            refreshContext(context);
            //完成加载
            afterRefresh(context, applicationArguments);
            //完成侦听器
            listeners.finished(context, null);
            //停止记时
            stopWatch.stop();
            //记录启动信息
            if (this.logStartupInfo) {
                new StartupInfoLogger(this.mainApplicationClass)
                        .logStarted(getApplicationLog(), stopWatch);
            }
            return context;
        }
        catch (Throwable ex) {
            handleRunFailure(context, listeners, analyzers, ex);
            throw new IllegalStateException(ex);
        }
    }
    
    
    private ConfigurableEnvironment prepareEnvironment(
            SpringApplicationRunListeners listeners,
            ApplicationArguments applicationArguments) {
            
        // 创建和配置环境    StandardServletEnvironment.customizePropertySources获取配置加载顺序
        ConfigurableEnvironment environment = getOrCreateEnvironment();
        
        
        //获取启动配置
        configureEnvironment(environment, applicationArguments.getSourceArgs());
        
        /**
        *通过 EventPublishingRunListener监听 发送ApplicationEnvironmentPreparedEvent 事件到下面监听器
        *加载配置以下配置的值并加载配置，并调用以下监听的 onApplicationEvent 方法
        *org.springframework.boot.context.config.ConfigFileApplicationListener   加载配置  
        *   获取org.springframework.boot.env.EnvironmentPostProcessor配置的值 
        *      org.springframework.boot.cloud.CloudFoundryVcapEnvironmentPostProcessor
        *          获取 spring cloud config VCAP_APPLICATION  和  VCAP_SERVICES  的配置 
        *
    *      org.springframework.boot.env.SpringApplicationJsonEnvironmentPostProcessor
    *          获取${spring.application.json:${SPRING_APPLICATION_JSON:}}  的配置
    *
        *      org.springframework.boot.context.config.ConfigFileApplicationListener
        *	    		添加属性源  [servletConfigInitParams,servletContextInitParams,systemProperties,systemEnvironment,random]
        *	    		获取 org.springframework.boot.env.PropertySourceLoader的值
        *	    		    org.springframework.boot.env.PropertiesPropertySourceLoader
        *	            org.springframework.boot.env.YamlPropertySourceLoader
        *	            配置文件路径加载顺序  1.获取用户自定义路径地址（spring.config.location的值） 2.[file:./config/, file:./, classpath:/config/, classpath:/]
        *	            文件加载顺序  1.获取用户自定义文件名（spring.config.name的值） 2.默认文件名（application）
        *	            文件后缀加载顺序： [properties, xml, yml, yaml]
        *	             1.file:./config/application.properties
        *	             2.file:./config/application.xml
        *	             3.file:./config/application.yml
        *	             4.file:./config/application.yaml
        *	             file:./application.properties
        *	             file:./application.xml
        *	             file:./application.yml
        *	             file:./application.yaml
        *	             file:./application.yaml
        *	             classpath:/config/application.properties
        *	             classpath:/config/application.xml
        *	             classpath:/config/application.yml
        *	             classpath:/config/application.yaml
        *	             //我配置的是放在  classpath下的
        *	             classpath:/application.properties
        *	             classpath:/application-dev.properties 
        *	        读取完配置，过滤spring bean
        *	        将配置绑定到  SpringApplication    
      *org.springframework.boot.context.config.AnsiOutputApplicationListener
      *org.springframework.boot.logging.LoggingApplicationListener
      *org.springframework.boot.logging.ClasspathLoggingApplicationListener
      *org.springframework.boot.autoconfigure.BackgroundPreinitializer
      *org.springframework.boot.context.config.DelegatingApplicationListener
      *org.springframework.boot.context.FileEncodingApplicationListener
      *
      *
      *
        */
        listeners.environmentPrepared(environment);
        if (!this.webEnvironment) {
            environment = new EnvironmentConverter(getClassLoader())
                    .convertToStandardEnvironmentIfNecessary(environment);
        }
        return environment;
    }
        
        
    /**
    * 配置优先级
    * StandardServletEnvironment.customizePropertySources
    * SERVLET_CONFIG_PROPERTY_SOURCE_NAME > SERVLET_CONTEXT_PROPERTY_SOURCE_NAME > JNDI_PROPERTY_SOURCE_NAME  > 系统属性 > 环境变量
    * servlet配置属性源名称 > servlet上下文属性源名称 > jndi属性源名称 > 系统属性 > 环境变量
    **/
    @Override
    protected void customizePropertySources(MutablePropertySources propertySources) {
        propertySources.addLast(new StubPropertySource(SERVLET_CONFIG_PROPERTY_SOURCE_NAME));
        propertySources.addLast(new StubPropertySource(SERVLET_CONTEXT_PROPERTY_SOURCE_NAME));
        if (JndiLocatorDelegate.isDefaultJndiEnvironmentAvailable()) {
            propertySources.addLast(new JndiPropertySource(JNDI_PROPERTY_SOURCE_NAME));
        }
        //获取系统属性、环境变量
        super.customizePropertySources(propertySources);
    }
    
    
    protected void configureEnvironment(ConfigurableEnvironment environment,
            String[] args) {
        //加载命令行属性
        configurePropertySources(environment, args);
        //获取 spring.profiles.active  的配置
        configureProfiles(environment, args);
    }
    

    
    
    @Override
    public void postProcessEnvironment(ConfigurableEnvironment environment,
            SpringApplication application) {
        addPropertySources(environment, application.getResourceLoader());
        //加载配置
        configureIgnoreBeanInfo(environment);
        绑定资源
        bindToSpringApplication(environment, application);
    }
    
    
    
    protected ConfigurableApplicationContext createApplicationContext() {
        Class<?> contextClass = this.applicationContextClass;
        if (contextClass == null) {
            try {
              /**
              * web项目 初始化  org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext
              * java项目  初始化 org.springframework.context.annotation.AnnotationConfigApplicationContext
              **/
                contextClass = Class.forName(this.webEnvironment
                        ? DEFAULT_WEB_CONTEXT_CLASS : DEFAULT_CONTEXT_CLASS);
            }
            catch (ClassNotFoundException ex) {
                throw new IllegalStateException(
                        "Unable create a default ApplicationContext, "
                                + "please specify an ApplicationContextClass",
                        ex);
            }
        }
        //初始化AnnotationConfigEmbeddedWebApplicationContext  注释Bean定义阅读器 类路径Bean定义扫描器
        return (ConfigurableApplicationContext) BeanUtils.instantiate(contextClass);
    }
    
    
    
    
    private void prepareContext(ConfigurableApplicationContext context,
            ConfigurableEnvironment environment, SpringApplicationRunListeners listeners,
            ApplicationArguments applicationArguments, Banner printedBanner) {
            
        /**
        * 注释Bean定义阅读器
        * 类路径Bean定义扫描器 
        **/	
        context.setEnvironment(environment);
        
        //上下文后处理
        postProcessApplicationContext(context);
        
        //初始化上下文
        applyInitializers(context);
        //上下文准备完成
        listeners.contextPrepared(context);
        if (this.logStartupInfo) {
            logStartupInfo(context.getParent() == null);
            logStartupProfileInfo(context);
        }

        //添加特殊的bean
        context.getBeanFactory().registerSingleton("springApplicationArguments",
                applicationArguments);
        if (printedBanner != null) {
            context.getBeanFactory().registerSingleton("springBootBanner", printedBanner);
        }

        // Load the sources
        Set<Object> sources = getSources();
        Assert.notEmpty(sources, "Sources must not be empty");
        
        //将bean加载到应用程序上下文中。
        load(context, sources.toArray(new Object[sources.size()]));
        //将context添加到监听中
        listeners.contextLoaded(context);
    }
    
    
    
    
    @Override
    public void refresh() throws BeansException, IllegalStateException {
        synchronized (this.startupShutdownMonitor) {
            
            //准备刷新上下文
            prepareRefresh();

            //告诉子类刷新内部bean工厂
            ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();

            // 准备在这个上下文中使用的bean工厂
            prepareBeanFactory(beanFactory);

            try {
                // 允许在上下文子类中对bean工厂进行后处理。
                postProcessBeanFactory(beanFactory);

                // 在上下文中调用在Bean中注册的工厂处理器
                invokeBeanFactoryPostProcessors(beanFactory);

                // Register bean processors that intercept bean creation.
                registerBeanPostProcessors(beanFactory);

                // Initialize message source for this context.
                initMessageSource();

                // Initialize event multicaster for this context.
                initApplicationEventMulticaster();

                // Initialize other special beans in specific context subclasses.
                onRefresh();

                // Check for listener beans and register them.
                registerListeners();

                // Instantiate all remaining (non-lazy-init) singletons.
                finishBeanFactoryInitialization(beanFactory);

                // Last step: publish corresponding event.
                finishRefresh();
            }

            catch (BeansException ex) {
                if (logger.isWarnEnabled()) {
                    logger.warn("Exception encountered during context initialization - " +
                            "cancelling refresh attempt: " + ex);
                }

                // Destroy already created singletons to avoid dangling resources.
                destroyBeans();

                // Reset 'active' flag.
                cancelRefresh(ex);

                // Propagate exception to caller.
                throw ex;
            }

            finally {
                // Reset common introspection caches in Spring's core, since we
                // might not ever need metadata for singleton beans anymore...
                resetCommonCaches();
            }
        }
    }
    
    
    
    protected void prepareRefresh() {
        this.startupDate = System.currentTimeMillis();
        this.closed.set(false);
        this.active.set(true);

        if (logger.isInfoEnabled()) {
            logger.info("Refreshing " + this);
        }

        // 在上下文环境中初始化任何占位符属性源
        initPropertySources();

        
        // 验证所有标记为必需的属性是可解析的
        getEnvironment().validateRequiredProperties();


        this.earlyApplicationEvents = new LinkedHashSet<ApplicationEvent>();
    }