Test against CGLIB memory leak for method injection

This commit introduces a test in XmlBeanFactoryTests that verifies that
CGLIB generated subclasses for method injected beans are reused across
bean factories for identical bean definitions. In other words, by
verifying that the same CGLIB generated class is reused for identical
bean definitions, we can be certain that Spring is no longer generating
identical, duplicate classes that consume memory in the VM.

Issue: SPR-10785, SPR-11420

spring-context/src/test/java/org/springframework/beans/factory/xml/XmlBeanFactoryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -27,8 +27,8 @@ import java.net.URL;
 import java.util.Map;
 
 import org.apache.commons.logging.LogFactory;
+
 import org.junit.Test;
-import org.xml.sax.InputSource;
 
 import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.aop.support.AopUtils;
@@ -61,20 +61,24 @@ import org.springframework.tests.sample.beans.IndexedTestBean;
 import org.springframework.tests.sample.beans.ResourceTestBean;
 import org.springframework.tests.sample.beans.TestBean;
 import org.springframework.tests.sample.beans.factory.DummyFactory;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.FileCopyUtils;
 import org.springframework.util.SerializationTestUtils;
 import org.springframework.util.StopWatch;
 
+import org.xml.sax.InputSource;
+
 import static org.hamcrest.CoreMatchers.*;
 import static org.junit.Assert.*;
 
 /**
  * Miscellaneous tests for XML bean definitions.
- *
+ * 
  * @author Juergen Hoeller
  * @author Rod Johnson
  * @author Rick Evans
  * @author Chris Beams
+ * @author Sam Brannen
  */
 public final class XmlBeanFactoryTests {
 
@@ -1283,6 +1287,31 @@ public final class XmlBeanFactoryTests {
 		}
 	}
 
+	/**
+	 * @since 3.2.8 and 4.0.2
+	 * @see <a href="https://jira.springsource.org/browse/SPR-10785">SPR-10785</a> and <a
+	 *      href="https://jira.springsource.org/browse/SPR-11420">SPR-11420</a>
+	 */
+	@Test
+	public void methodInjectedBeanMustBeOfSameEnhancedCglibSubclassTypeAcrossBeanFactories() {
+		Class<?> firstClass = null;
+
+		for (int i = 1; i <= 10; i++) {
+			DefaultListableBeanFactory bf = new DefaultListableBeanFactory();
+			new XmlBeanDefinitionReader(bf).loadBeanDefinitions(OVERRIDES_CONTEXT);
+
+			final Class<?> currentClass = bf.getBean("overrideOneMethod").getClass();
+			assertTrue("Method injected bean class [" + currentClass + "] must be a CGLIB enhanced subclass.",
+				ClassUtils.isCglibProxyClass(currentClass));
+
+			if (firstClass == null) {
+				firstClass = currentClass;
+			}
+			else {
+				assertEquals(firstClass, currentClass);
+			}
+		}
+	}
 
 	@Test
 	public void testLookupOverrideMethodsWithSetterInjection() {
@@ -1915,6 +1944,7 @@ public final class XmlBeanFactoryTests {
 			this.tb = tb;
 		}
 
+		@SuppressWarnings("rawtypes")
 		public LenientDependencyTestBean(Map[] m) {
 			throw new IllegalStateException("Don't pick this constructor");
 		}