Spring加载后置处理器方式之模板方法

1. 未使用模板方法时

 public static void main(String[] args) {MyBeanFactory myBeanFactory = new MyBeanFactory();myBeanFactory.getBean();}static class MyBeanFactory {public Object getBean() {Object bean = new Object();System.out.println("构造...." + bean);System.out.println("依赖注入...." + bean);//需在此手动加载，代码高度耦合System.out.println("初始化...." + bean);return bean;}}

2. 使用模板方法后

仅需在生成对象后添加后置处理器，对MyBeanFactory无需修改，实现代码解耦和

 public static void main(String[] args) {MyBeanFactory myBeanFactory = new MyBeanFactory();myBeanFactory.addBeanPostProcessor(bean -> {System.out.println("解析了@Autowired");});myBeanFactory.addBeanPostProcessor(bean -> {System.out.println("解析了@Resource");});myBeanFactory.getBean();}static class MyBeanFactory {public Object getBean() {Object bean = new Object();System.out.println("构造...." + bean);System.out.println("依赖注入...." + bean);beanPostProcessors.forEach(i -> {i.inject(bean);});System.out.println("初始化...." + bean);return bean;}private List<BeanPostProcessor> beanPostProcessors = new ArrayList<>();public void addBeanPostProcessor(BeanPostProcessor beanPostProcessor) {beanPostProcessors.add(beanPostProcessor);}}static interface BeanPostProcessor {//增强依赖注入阶段,解析@Autowired @Resource注解public void inject(Object bean);}