spring 自定义注解

参考Spring-Retry实现。

包含三个文件： LogConfiguration.java LogInterceptor.java Log.java

直接上代码

LogConfiguration.java

@Configuration public class LogConfiguration extends AbstractPointcutAdvisor implements IntroductionAdvisor,BeanFactoryAware{ private Advice advice; private Pointcut pointcut; private BeanFactory beanFactory; @PostConstruct public void init(){ Set<Class<? extends Annotation>> annotationTypes=new LinkedHashSet<>(1); annotationTypes.add(Log.class); this.pointcut=buildPointcut(annotationTypes); this.advice=buildAdvice(); if(this.advice instanceof BeanFactoryAware){ ((BeanFactoryAware)this.advice).setBeanFactory(beanFactory); } } protected Advice buildAdvice() { LogInterceptor interceptor = new LogInterceptor(); return interceptor; } protected Pointcut buildPointcut(Set<Class<? extends Annotation>> retryAnnotationTypes) { ComposablePointcut result = null; for (Class<? extends Annotation> retryAnnotationType : retryAnnotationTypes) { Pointcut filter = new AnnotationClassOrMethodPointcut(retryAnnotationType); if (result == null) { result = new ComposablePointcut(filter); } else { result.union(filter); } } return result; } private final class AnnotationClassOrMethodPointcut extends StaticMethodMatcherPointcut { private final MethodMatcher methodResolver; AnnotationClassOrMethodPointcut(Class<? extends Annotation> annotationType) { this.methodResolver = new AnnotationMethodMatcher(annotationType); setClassFilter(new AnnotationClassOrMethodFilter(annotationType)); } @Override public boolean matches(Method method, Class<?> targetClass) { return getClassFilter().matches(targetClass) || this.methodResolver.matches(method, targetClass); } } private final class AnnotationClassOrMethodFilter extends AnnotationClassFilter { private final AnnotationMethodsResolver methodResolver; AnnotationClassOrMethodFilter(Class<? extends Annotation> annotationType) { super(annotationType, true); this.methodResolver = new AnnotationMethodsResolver(annotationType); } @Override public boolean matches(Class<?> clazz) { return super.matches(clazz) || this.methodResolver.hasAnnotatedMethods(clazz); } } private static class AnnotationMethodsResolver { private Class<? extends Annotation> annotationType; public AnnotationMethodsResolver(Class<? extends Annotation> annotationType) { this.annotationType = annotationType; } public boolean hasAnnotatedMethods(Class<?> clazz) { final AtomicBoolean found = new AtomicBoolean(false); ReflectionUtils.doWithMethods(clazz, new ReflectionUtils.MethodCallback() { @Override public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException { if (found.get()) { return; } Annotation annotation = AnnotationUtils.findAnnotation(method, annotationType); if (annotation != null) { found.set(true); } } }); return found.get(); } } @Override public ClassFilter getClassFilter() { return pointcut.getClassFilter(); } @Override public void validateInterfaces() throws IllegalArgumentException { } @Override public Advice getAdvice() { return advice; } @Override public Class<?>[] getInterfaces() { return new Class<?>[]{Log.class}; } @Override public Pointcut getPointcut() { return pointcut; } @Override public void setBeanFactory(BeanFactory beanFactory) throws BeansException { this.beanFactory=beanFactory; } }

Log.java

@Retention(RetentionPolicy.RUNTIME) @Target({ElementType.METHOD,ElementType.TYPE}) @Documented public @interface Log { }

LogInterceptor.java

public class LogInterceptor implements IntroductionInterceptor,BeanFactoryAware{ private BeanFactory beanFactory; @Override public Object invoke(MethodInvocation invocation) throws Throwable { Method method=invocation.getMethod(); Log log = AnnotationUtils.findAnnotation(method, Log.class); if (log == null) { log = AnnotationUtils.findAnnotation(method.getDeclaringClass(), Log.class); } if (log == null) { log = findAnnotationOnTarget(invocation.getThis(), method); } if(log!=null) { System.out.println("invoke:" + invocation.getMethod().getName()); } return invocation.proceed(); } private Log findAnnotationOnTarget(Object target, Method method) { try { Method targetMethod = target.getClass().getMethod(method.getName(), method.getParameterTypes()); return AnnotationUtils.findAnnotation(targetMethod, Log.class); } catch (Exception e) { return null; } } @Override public boolean implementsInterface(Class<?> intf) { return Log.class.isAssignableFrom(intf); } @Override public void setBeanFactory(BeanFactory beanFactory) throws BeansException { this.beanFactory=beanFactory; } }