Spring源码之核心容器

public interface BeanFactory {
    //对FactoryBean的转义定义，因为如果使用bean的名字检索FactoryBean得到的对象是工厂生成的对象，
    //如果需要得到工厂本身，需要转义
    String FACTORY_BEAN_PREFIX = "&";

    //根据bean的名字，获取在IOC容器中得到bean实例
    Object getBean(String name) throws BeansException;
    //根据bean的名字和Class类型来得到bean实例，增加了类型安全验证机制。
    <T> T getBean(String name, @Nullable Class<T> requiredType) throws BeansException;
    Object getBean(String name. Object...args) throws BeansException;
    <T> T getBean(Class<T> requiredType) throws BeansException;
    <T> T getBean(Class<T> requiredType, Object... args) throws BeansException;

    //提供对bean的检索，看看是否在IOC容器有这个名字的bean
    boolean corrtainsBean(String name);

    //根据bean名字得到bean实例，并同时判断这个bean是不是单例
    boolean isSingleton(String nane) throws NoSuchBeanDefinitionException;
    boolean isPrototype(String nane) throws NoSuchBeanDefinitionException;
    boolean isTypeMatch(String nane, ResolvableType typeToMatch) throws NoSuchBeanDefinitionException;
    boolean isTypeMatch(String nane, @Nullable Class<?> typeToMatch) throws NoSuc hBeanDefinit ionExcept ion;

    //得到bean实例的Class类型
    @Nullable
    Class<?> getType(String name) throws NoSuchBeanDefinitionException;

    //得到bean的别名，如果根据别名检索，那么其原名也会被检索出来
    String[] getAliases(String nane);

    public FileSystemXmlApplicationContext(String configLocation) throws BeansException {
        this(new String[] {configLocation}, true, null);
    }
    public FileSystemXmlApplicationContext(String... configLocations) throws BeansException {
        this(configLocations, true, null);
    }
    //实际都是在调用这个构造函数
    public FileSystemXmlApplicationContext(String[] configLocations, boolean refresh, ApplicationContext parent) throws BeansException {
        super(parent);
        setConfigLocations(configLocations);
        if (refresh) {
            refresh();
        }
    }

    public abstract class AbstractApplicationContext extends DefaultResourceLoader
            implements ConfigurableApplicationContext {

        //静态初始化块，在整个容器创建过程中只执行一次
        static {
            // 为了避免应用程序在Weblogic8.1关闭时出现类加载异常加载问题，加载IOC容
            // 器关闭事件(ContextClosedEvent)类
            ContextClosedEvent.class.getName();
        }
        //super方法一直传递到这里
        public AbstractApplicationContext(ApplicationContext parent) {
            this();
            setParent(parent);
        }
        // 第一步调用空构造，进一步调用getResourcePatternResolver方法
        public AbstractApplicationContext() {
            this.resourcePatternResolver = getResourcePatternResolver();
        }

        //获取一个Spring Source的加载器用于读入Spring Bean定义资源文件
        protected ResourcePatternResolver getResourcePatternResolver() {
            //AbstractApplicationContext 继承 DefaultResourceLoader，因此也是一个资源加载器
            //Spring资源加载器，其getResource(String location)方法用于载入资源
            return new PathMatchingResourcePatternResolver(this);
        }
        /** 省略很多代码*/
    }

    public PathMatchingResourcePatternResolver(ResourceLoader resourceLoader) {
        Assert.notNull(resourceLoader, "ResourceLoader must not be null");
        //设置Spring的资源加载器
        this.resourceLoader = resourceLoader;
    }

    //处理单个资源文件路径为一个字符串的情况
    public void setConfigLocation(String location) {
        //String CONFIG_LOCATION_DELIMITERS =    ", ; \t\n”；
        //即多个资源文件路径之间用", ; \t\n”分隔，解析成数组形式
        setConfigLocations(StringUtils.tokenizeToStringArray(location, CONFIG_LOCATION_DELIMITERS));
    }
    //解析Bean定义资源文件的路径，处理多个资源文件字符串数组
    public void setConfigLocations(String... locations) {
        if (locations != null) {
            Assert.noNullElements(locations, "Config locations must not be null");
            this.configLocations = new String[locations.length];
            for (int i = 0; i < locations.length; i++) {
                // resolvePath 同一个类中将字符串解析为路径的方法
                this.configLocations[i] = resolvePath(locations[i]).trim();
            }
        }
        else {
            this.configLocations = null;
        }
    }

public void refresh  throws BeansExceptlon, IllegalStateException (
    synchronized (this.startupShutdownMonitor) (
    //调用容器准备刷新的方法，获取容器的当时时间.同时给容器设置同步标识
    prepareRefresh();
    //告诉子类启动refreshBeanFactory()方法，Bean定义资源文件的载入从
    //子类的refreshBeanFactory()方法启动
    ConfigurableListableBeanFactory beanFactory = obtalnFreshBeanFactory();
    //为BeanFactory配置容器特性，例如类加载器、事件处理器等
    prepareBeanFactory(beanFactory);
    try {
        //为容器的某些于类指定特殊的BeanPost事件处理器
        postProcessBeanFactory(beanFactory);
        //调用所有注册的 BeanFactoryPostProcessor 的 Bean
        InvokeBeanFactoryPostProcessors(beanFactory);
        //为BeanFactory注朋BeanPost事件处理悬.
        //BeanPostProcessor是Bean后置处理器，用于监听容器触发的事件
        registerBeanPostProcessors(beanFactory);
        //初始化信息源，和国际化相关.
        lnitMessageSource();
        //初始化容器事件传播器.
        InitAppllcationEventHulticaster();
        //调用子类的某些特殊Bean初始化方法
        onRefresh();
        //为事件传播器注明事件监听器.
        registerListeners();
        //初始化所有剩余的单例Bean
        flnishBeanFactorylnitialization(beanFactory);
        //初始化容器的生命周期事件处理器，并发布容器的生命周期事件
        finishRefresh();
    }
    catch (BeansException ex) {
        if (logger.isMamEnabled() {
        logger.wam("Exception encountered during context initialization - " + "cancelling refresh attempt: " + ex);
    }
    //x销毁已创建的Bean
    destroySeans();
    // 取消refresh 操作,重置容器的同步标识.
    cancelR«fresh(ex);
    throw ex;
    ｝
    finally {
        resetComonCaches ();
    ｝
｝

protected ConfigurableListableBeanFactory obtainFreshBeanFactory() {
        refreshBeanFactory();
        ConfigurableListableBeanFactory beanFactory = getBeanFactory();
        if (logger.isDebugEnabled()) {
            logger.debug("Bean factory for " + getDisplayName() + ": " + beanFactory);
        }
        return beanFactory;
    }