《_java学习学习过程中的一些笔记》.docVIP

通过java代理模式实现以下模式： 1：接口不用通过实现就可以调用其方法： //注解的使用，javax.persistence 持久化包 public class TestProxy { public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException, IntrospectionException, IOException { // PropertyDescriptor[] ps = Introspector.getBeanInfo(FactoryImpl.class) // .getPropertyDescriptors(); System.out.println(start); ProxyFactory factory = new ProxyFactory(); UserService s = (UserService) factory .getBean(new Class[] { UserService.class }); s.findByUserName(xxx); System.out.println(end); int s1 = System.in.read(); System.out.println(s1); } } class ProxyFactory { private Object ret = null; public Object getBean(Class[] cls) { ret = Proxy.newProxyInstance(ClassLoader.getSystemClassLoader(), cls, new ProxyInvocationHandler()); return ret; } static class ProxyInvocationHandler implements InvocationHandler { @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { System.out.println(method.getName()); Query query = method.getAnnotation(Query.class); if (query != null) { System.out.println(query.value()); } return null; } } } class User implements Serializable { private static final long serialVersionUID = 1L; String username; String password; } class Person implements Serializable { private static final long serialVersionUID = 1L; String pusername; String ppassword; } @Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) @interface Query { String value() default ; } interface ServiceT, ID extends Serializable { } interface UserService extends ServiceUser, String { @Query(test select findbyusername111) public User findByUserName(String name); } interface PersonService extends ServicePerson, String { @Query(select findbypersonname) public Person findByPersonName(String name); } 2：java代理模式，个人见解 //代理方法，使用抽象类的好处就是代理对象只需要实现需要的方法就行了 abstract class Service { public void callback() {} public