Consider abstract classes with @Lookup methods as candidate components

Issue: SPR-14550

spring-context/src/test/java/example/profilescan/DevComponent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2010 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -30,7 +30,7 @@ import org.springframework.stereotype.Component;
 @Component
 public @interface DevComponent {
 
-	public static final String PROFILE_NAME = "dev";
+	String PROFILE_NAME = "dev";
 
 	String value() default "";
 

spring-context/src/test/java/example/profilescan/ProfileAnnotatedComponent.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright 2002-2017 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 example.profilescan;
 
 import org.springframework.context.annotation.Profile;
@@ -8,6 +24,7 @@ import org.springframework.stereotype.Component;
 public class ProfileAnnotatedComponent {
 
 	public static final String BEAN_NAME = "profileAnnotatedComponent";
+
 	public static final String PROFILE_NAME = "test";
 
 }

spring-context/src/test/java/example/profilescan/ProfileMetaAnnotatedComponent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2010 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -16,10 +16,9 @@
 
 package example.profilescan;
 
-
 @DevComponent(ProfileMetaAnnotatedComponent.BEAN_NAME)
 public class ProfileMetaAnnotatedComponent {
 
 	public static final String BEAN_NAME = "profileMetaAnnotatedComponent";
 
-}
+}

spring-context/src/test/java/example/profilescan/SomeAbstractClass.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2002-2017 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 example.profilescan;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public abstract class SomeAbstractClass {
+
+}

spring-context/src/test/java/example/scannable/FooServiceImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -24,6 +24,7 @@ import javax.annotation.PostConstruct;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.ListableBeanFactory;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Lookup;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.ConfigurableApplicationContext;
@@ -42,7 +43,7 @@ import org.springframework.util.Assert;
  * @author Juergen Hoeller
  */
 @Service @Lazy @DependsOn("myNamedComponent")
-public class FooServiceImpl implements FooService {
+public abstract class FooServiceImpl implements FooService {
 
 	// Just to test ASM5's bytecode parsing of INVOKESPECIAL/STATIC on interfaces
 	private static final Comparator<MessageBean> COMPARATOR_BY_MESSAGE = Comparator.comparing(MessageBean::getMessage);
@@ -84,11 +85,15 @@ public class FooServiceImpl implements FooService {
 		return this.fooDao.findFoo(id);
 	}
 
+	public String lookupFoo(int id) {
+		return fooDao().findFoo(id);
+	}
+
 	@Override
 	public Future<String> asyncFoo(int id) {
 		System.out.println(Thread.currentThread().getName());
 		Assert.state(ServiceInvocationCounter.getThreadLocalCount() != null, "Thread-local counter not exposed");
-		return new AsyncResult<>(this.fooDao.findFoo(id));
+		return new AsyncResult<>(fooDao().findFoo(id));
 	}
 
 	@Override
@@ -96,4 +101,8 @@ public class FooServiceImpl implements FooService {
 		return this.initCalled;
 	}
 
+
+	@Lookup
+	protected abstract FooDao fooDao();
+
 }