点此返回

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public class AtBeanPostProcessor implements BeanFactoryPostProcessor {
    @Override
    public void postProcessBeanFactory
            (ConfigurableListableBeanFactory configurableListableBeanFactory)
            throws BeansException {
        try {
            //读取类信息
            CachingMetadataReaderFactory factory = new CachingMetadataReaderFactory();
            MetadataReader reader = factory
                    .getMetadataReader(new ClassPathResource("com/itheima/a05/Config.class"));
            //获取被@Bean标注的方法
            //1.获取和注解相关的元数据
            //2.进一步获取被@Bean注解标注的方法
            Set<MethodMetadata> methods = reader
                    .getAnnotationMetadata()
                    .getAnnotatedMethods(Bean.class.getName());

            for (MethodMetadata method : methods) {
                System.out.println(method);
                //解析@Bean注解中的属性
                String initMethod = (String) 
                        method.getAnnotationAttributes(Bean.class.getName()).get("initMethod");
                //利用BeanDefinitionBuilder获取BeanDefinition，并加入bean工厂
                BeanDefinitionBuilder builder = BeanDefinitionBuilder.genericBeanDefinition();
                builder.setFactoryMethodOnBean(method.getMethodName(),"config");
                //指定自动装配模式(因为SqlSessionFactoryBean有一个dataSource参数)
                builder.setAutowireMode(AbstractBeanDefinition.AUTOWIRE_CONSTRUCTOR);
                if (initMethod.length() > 0){
                    builder.setInitMethodName(initMethod);
                }
                AbstractBeanDefinition bd = builder.getBeanDefinition();
                //注册Bean到容器中
                if (configurableListableBeanFactory 
                        instanceof DefaultListableBeanFactory beanFactory) {
                    beanFactory.registerBeanDefinition(method.getMethodName(),bd);
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

当其他类调用时，只需调用容器的registerBean方法，传入对实现类.class文件即可

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public class BeanApp {
    private static final Logger log = LoggerFactory.getLogger(BeanApp.class);
    public static void main(String[] args) throws IOException {
        //创建一个干净容器
        GenericApplicationContext context = new GenericApplicationContext();
        context.registerBean("config", Config.class);

        //解析@Bean
        context.registerBean(AtBeanPostProcessor.class);

        //初始化容器
        context.refresh();
        for (String name : context.getBeanDefinitionNames()) {
            System.out.println(name);
        }
        //销毁容器
        context.close();
    }
}