Spring源码解析-实例化bean对象

　　

　　spring加载配置文件，AbstractApplicationContext类中的refresh方法起着重要的作用。

@Override

    public void refresh() throws BeansException, IllegalStateException {

        synchronized (this.startupShutdownMonitor) {

            // Prepare this context for refreshing.准备刷新context

            prepareRefresh();

            // Tell the subclass to refresh the internal bean factory.刷新子类beanFactory，注册beanDefinition

            ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();

            // Prepare the bean factory for use in this context.准备beanfactory

            prepareBeanFactory(beanFactory);

            try {

                // Allows post-processing of the bean factory in context subclasses.

                postProcessBeanFactory(beanFactory);

                // Invoke factory processors registered as beans in the context.

                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.初始化非懒加载的bean实例

                finishBeanFactoryInitialization(beanFactory);

                // Last step: publish corresponding event.

                finishRefresh();

            }

            catch (BeansException ex) {

                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;

            }

        }

    }

实例化bean对象，主要的是在

finishBeanFactoryInitialization(beanFactory)

方法。
大致的流程图（下部分）：

（点击查看大图）

下面分析实例化bean对象的源码分析

加载bean对象：

在AbstractBeanFactory类中，根据不同scope进行实例化，例如Singleton,Prototype等

根据不同情况采用不同的代理方式：

到这里就是bean实例的初始化，可以看到spring采用的代理方式，来实现bean的初始化。