Fix nested @component annotation instantiation bug

3.1 M2 introduced a regression that causes false positives during
@configuration class candidate checks. Now performing a call to
AnnotationMetadata#isInterface in addition to checks for @component and
@bean annotations when determining whether a candidate is a 'lite'
configuration class. Annotations are in the end interfaces, so both
are filtered out at once.

Issue: SPR-8761

Author: cbeams

org.springframework.context/src/main/java/org/springframework/context/annotation/ConfigurationClassUtils.java

@@ -100,8 +100,9 @@ public static boolean isFullConfigurationCandidate(AnnotationMetadata metadata)
 	}
 
 	public static boolean isLiteConfigurationCandidate(AnnotationMetadata metadata) {
-		return metadata.isAnnotated(Component.class.getName()) ||
-				metadata.hasAnnotatedMethods(Bean.class.getName());
+		return !metadata.isInterface() && // not an interface or an annotation
+				(metadata.isAnnotated(Component.class.getName()) ||
+				metadata.hasAnnotatedMethods(Bean.class.getName()));
 	}
 
 

org.springframework.context/src/test/java/org/springframework/context/annotation/spr8761/Spr8761Tests.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2002-2011 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.context.annotation.spr8761;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.junit.Test;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.stereotype.Component;
+
+/**
+ * Tests cornering the regression reported in SPR-8761.
+ *
+ * @author Chris Beams
+ */
+public class Spr8761Tests {
+
+	/**
+	 * Prior to the fix for SPR-8761, this test threw because the nested MyComponent
+	 * annotation was being falsely considered as a 'lite' Configuration class candidate.
+	 */
+	@Test
+	public void repro() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.scan(getClass().getPackage().getName());
+		ctx.refresh();
+		assertThat(ctx.containsBean("withNestedAnnotation"), is(true));
+	}
+
+}
+
+@Component
+class WithNestedAnnotation {
+
+	@Retention(RetentionPolicy.RUNTIME)
+	@Component
+	public static @interface MyComponent {
+	} 
+}