Add TYPE_HIERARCHY_AND_ENCLOSING_CLASSES strategy

Add a `TYPE_HIERARCHY_AND_ENCLOSING_CLASSES` annotation search strategy
that can be used to search the full type hierarchy as well as any
enclosing classes.

Closes gh-23378

spring-core/src/test/java/org/springframework/core/annotation/AnnotationEnclosingClassSample.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      https://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.core.annotation;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Example class used to test {@link AnnotationsScanner} with enclosing classes.
+ *
+ * @author Phillip Webb
+ * @since 5.2
+ */
+@AnnotationEnclosingClassSample.EnclosedOne
+public class AnnotationEnclosingClassSample {
+
+	@EnclosedTwo
+	public static class EnclosedStatic {
+
+		@EnclosedThree
+		public static class EnclosedStaticStatic {
+
+		}
+
+	}
+
+	@EnclosedTwo
+	public class EnclosedInner {
+
+		@EnclosedThree
+		public class EnclosedInnerInner {
+
+		}
+
+	}
+
+	@Retention(RetentionPolicy.RUNTIME)
+	public static @interface EnclosedOne {
+
+	}
+
+	@Retention(RetentionPolicy.RUNTIME)
+	public static @interface EnclosedTwo {
+
+	}
+
+	@Retention(RetentionPolicy.RUNTIME)
+	public static @interface EnclosedThree {
+
+	}
+
+}

spring-core/src/test/java/org/springframework/core/annotation/AnnotationsScannerTests.java

@@ -454,6 +454,29 @@ public class AnnotationsScannerTests {
 				"0:TestAnnotation1");
 	}
 
+	@Test
+	public void typeHierarchyWithEnclosedStrategyOnEnclosedStaticClassScansAnnotations() {
+		Class<?> source = AnnotationEnclosingClassSample.EnclosedStatic.EnclosedStaticStatic.class;
+		assertThat(scan(source, SearchStrategy.TYPE_HIERARCHY_AND_ENCLOSING_CLASSES))
+				.containsExactly("0:EnclosedThree", "1:EnclosedTwo", "2:EnclosedOne");
+	}
+
+	@Test
+	public void typeHierarchyWithEnclosedStrategyOnEnclosedInnerClassScansAnnotations() {
+		Class<?> source = AnnotationEnclosingClassSample.EnclosedInner.EnclosedInnerInner.class;
+		assertThat(scan(source, SearchStrategy.TYPE_HIERARCHY_AND_ENCLOSING_CLASSES))
+				.containsExactly("0:EnclosedThree", "1:EnclosedTwo", "2:EnclosedOne");
+	}
+
+	@Test
+	public void typeHierarchyWithEnclosedStrategyOnMethodHierarchyUsesTypeHierarchyScan() {
+		Method source = methodFrom(WithHierarchy.class);
+		assertThat(scan(source, SearchStrategy.TYPE_HIERARCHY_AND_ENCLOSING_CLASSES)).containsExactly(
+				"0:TestAnnotation1", "1:TestAnnotation5", "1:TestInheritedAnnotation5",
+				"2:TestAnnotation6", "3:TestAnnotation2", "3:TestInheritedAnnotation2",
+				"4:TestAnnotation3", "5:TestAnnotation4");
+	}
+
 	@Test
 	public void scanWhenProcessorReturnsFromDoWithAggregateExitsEarly() {
 		String result = AnnotationsScanner.scan(this, WithSingleSuperclass.class,