Introduce @EnableLoadTimeWeaving

Issue: SPR-8317

org.springframework.context/src/test/java/org/springframework/context/annotation/EnableLoadTimeWeavingTests-context.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:context="http://www.springframework.org/schema/context"
+	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
+		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">
+
+	<context:load-time-weaver weaver-class="org.springframework.instrument.classloading.SimpleLoadTimeWeaver"/>
+
+</beans>

org.springframework.context/src/test/java/org/springframework/context/annotation/EnableLoadTimeWeavingTests.java

@@ -0,0 +1,55 @@
+/*
+ * 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;
+
+import org.junit.Test;
+import org.springframework.context.support.GenericXmlApplicationContext;
+import org.springframework.instrument.classloading.LoadTimeWeaver;
+import org.springframework.instrument.classloading.SimpleLoadTimeWeaver;
+
+/**
+ * Unit tests for @EnableLoadTimeWeaving
+ *
+ * @author Chris Beams
+ * @since 3.1
+ */
+public class EnableLoadTimeWeavingTests {
+
+	@Test
+	public void control() {
+		GenericXmlApplicationContext ctx =
+			new GenericXmlApplicationContext(getClass(), "EnableLoadTimeWeavingTests-context.xml");
+		ctx.getBean("loadTimeWeaver");
+	}
+
+	@Test
+	public void test() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.register(Config.class);
+		ctx.refresh();
+		ctx.getBean("loadTimeWeaver");
+	}
+
+	@Configuration
+	@EnableLoadTimeWeaving
+	static class Config implements LoadTimeWeavingConfigurer {
+
+		public LoadTimeWeaver getLoadTimeWeaver() {
+			return new SimpleLoadTimeWeaver();
+		}
+	}
+}