spring 源码分析笔记

spring 源码分析笔记

1.入口

ClassPathXmlApplicationContext#ClassPathXmlApplicationContext

AbstractApplicationContext#refresh()

 public void refresh() throws BeansException, IllegalStateException {
        synchronized(this.startupShutdownMonitor) {
            // 初始化 一下 配置 环境信息 
            this.prepareRefresh();
            //工厂初始化
            ConfigurableListableBeanFactory beanFactory = this.obtainFreshBeanFactory();
            this.prepareBeanFactory(beanFactory);

            try {
                this.postProcessBeanFactory(beanFactory);
                this.invokeBeanFactoryPostProcessors(beanFactory);
                this.registerBeanPostProcessors(beanFactory);
                this.initMessageSource();
                this.initApplicationEventMulticaster();
                // springmvc 调用 并且 设置了 applicationContext
                this.onRefresh();
                this.registerListeners();
                this.finishBeanFactoryInitialization(beanFactory);
                this.finishRefresh();
            } catch (BeansException var9) {
                if (this.logger.isWarnEnabled()) {
                    this.logger.warn("Exception encountered during context initialization - cancelling refresh attempt: " + var9);
                }

                this.destroyBeans();
                this.cancelRefresh(var9);
                throw var9;
            } finally {
                this.resetCommonCaches();
            }

        }
    }

2.初始化工厂 涉及到 解析xml 注册 BeanDefinition

1. AbstractApplicationContext#obtainFreshBeanFactory()

2. this.refreshBeanFactory();

3. AbstractRefreshableApplicationContext#refreshBeanFactory()
// 载入所有 BeanDefinition 
4. this.loadBeanDefinitions(beanFactory);

5. AbstractXmlApplicationContext#loadBeanDefinitions

6. this.loadBeanDefinitions

7. reader.loadBeanDefinitions(configResources);

8. this.loadBeanDefinitions

9. XmlBeanDefinitionReader#loadBeanDefinitions

10. this.doLoadBeanDefinitions
// 注册所有 的bean 定义 信息
11. this.registerBeanDefinitions(doc, resource);

12.  documentReader.registerBeanDefinitions(doc, this.createReaderContext(resource));

13.  this.doRegisterBeanDefinitions(doc.getDocumentElement());
// 委派 给 解析器 解析 XML 解析成 bean 定义 信息
14.  this.parseBeanDefinitions(root, this.delegate);

15. DefaultBeanDefinitionDocumentReader#parseBeanDefinitions

16.  this.parseDefaultElement(ele, delegate);

17.  
 private void parseDefaultElement(Element ele,  BeanDefinitionParserDelegate delegate) {
        if (delegate.nodeNameEquals(ele, "import")) {
            this.importBeanDefinitionResource(ele);
        } else if (delegate.nodeNameEquals(ele, "alias")) {
            this.processAliasRegistration(ele);
        } else if (delegate.nodeNameEquals(ele, "bean")) {
        // 解析 开始
            this.processBeanDefinition(ele, delegate);
        } else if (delegate.nodeNameEquals(ele, "beans")) {
            this.doRegisterBeanDefinitions(ele);
        }

    }
    
18.  BeanDefinitionReaderUtils.registerBeanDefinition(bdHolder, this.getReaderContext().getRegistry());
// registry 就是 DefaultListableBeanFactory 接口
19. registry.registerBeanDefinition(beanName, definitionHolder.getBeanDefinition());

20. DefaultListableBeanFactory#registerBeanDefinition(String beanName, BeanDefinition beanDefinition)

//完成了 bean 定义的解析 过程 放入map 
21. private final Map<String, BeanDefinition> beanDefinitionMap = new ConcurrentHashMap(256);