jdbctemplate連接池，Spring-MetadataReader接口

作用：對一個類的各種元數據都封裝成一個MetadataReader對象，以下是獲取MetadataReader對象的方式之一

public static void main(String[] args) throws IOException, ClassNotFoundException {Set<BeanDefinition> candidates = new LinkedHashSet<>();ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();  Resource[] resources = resourcePatternResolver.getResources("classpath*:com/my/*/*.**");  MetadataReaderFactory metadata=new SimpleMetadataReaderFactory();for(Resource resource:resources) {MetadataReader metadataReader=metadata.getMetadataReader(resource);ScannedGenericBeanDefinition sbd = new ScannedGenericBeanDefinition(metadataReader);sbd.setResource(resource);sbd.setSource(resource);candidates.add(sbd);}for(BeanDefinition beanDefinition : candidates) {  String classname=beanDefinition.getBeanClassName();Controller c=Class.forName(classname).getAnnotation(Controller.class);Service s=Class.forName(classname).getAnnotation(Service.class);Component component=Class.forName(classname).getAnnotation(Component.class);if(c!=null ||s!=null ||component!=null)System.out.println(classname);} }