Retry annotation detected on implementing class

Fixes gh-88, closes gh-90

src/main/java/org/springframework/retry/annotation/AnnotationAwareRetryOperationsInterceptor.java

@@ -195,7 +195,12 @@ public class AnnotationAwareRetryOperationsInterceptor implements IntroductionIn
 	private Retryable findAnnotationOnTarget(Object target, Method method) {
 		try {
 			Method targetMethod = target.getClass().getMethod(method.getName(), method.getParameterTypes());
-			return AnnotationUtils.findAnnotation(targetMethod, Retryable.class);
+			Retryable retryable = AnnotationUtils.findAnnotation(targetMethod, Retryable.class);
+			if (retryable == null) {
+				retryable = AnnotationUtils.findAnnotation(targetMethod.getDeclaringClass(), Retryable.class);
+			}
+
+			return retryable;
 		}
 		catch (Exception e) {
 			return null;

src/test/java/org/springframework/retry/annotation/EnableRetryTests.java

@@ -168,6 +168,17 @@ public class EnableRetryTests {
 		context.close();
 	}
 
+	@Test
+	public void testImplementation() {
+		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(TestConfiguration.class);
+		NotAnnotatedInterface service = context.getBean(NotAnnotatedInterface.class);
+		service.service1();
+		service.service2();
+		assertEquals(5, service.getCount());
+		context.close();
+	}
+
+
 	@Test
 	public void testExpression() throws Exception {
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(
@@ -321,6 +332,11 @@ public class EnableRetryTests {
 			return new TheClass();
 		}
 
+		@Bean
+		public NotAnnotatedInterface notAnnotatedInterface() {
+			return new RetryableImplementation();
+		}
+
 	}
 
 	protected static class Service {
@@ -538,4 +554,41 @@ public class EnableRetryTests {
 
 	}
 
+	public static interface NotAnnotatedInterface {
+
+		void service1();
+
+		void service2();
+
+		int getCount();
+
+	}
+
+	@Retryable
+	public static class RetryableImplementation implements NotAnnotatedInterface {
+
+		private int count = 0;
+
+		@Override
+		public void service1() {
+			if (count++ < 2) {
+				throw new RuntimeException("Planned");
+			}
+		}
+
+		@Override
+		public void service2() {
+			if (count++ < 4) {
+				throw new RuntimeException("Planned");
+			}
+		}
+
+		@Override
+		public int getCount() {
+			return count;
+		}
+
+	}
+
+
 }