CachedIntrospectionResults.clearClassLoader(null) removes cached classes for the system class loader

Issue: SPR-9189

org.springframework.beans/src/main/java/org/springframework/beans/CachedIntrospectionResults.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2010 the original author or authors.
+ * Copyright 2002-2013 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.
@@ -100,9 +100,6 @@ public class CachedIntrospectionResults {
 	 * @param classLoader the ClassLoader to clear the cache for
 	 */
 	public static void clearClassLoader(ClassLoader classLoader) {
-		if (classLoader == null) {
-			return;
-		}
 		synchronized (classCache) {
 			for (Iterator<Class> it = classCache.keySet().iterator(); it.hasNext();) {
 				Class beanClass = it.next();
@@ -183,12 +180,12 @@ public class CachedIntrospectionResults {
 	 * @param parent the parent ClassLoader to check for
 	 */
 	private static boolean isUnderneathClassLoader(ClassLoader candidate, ClassLoader parent) {
-		if (candidate == null) {
-			return false;
-		}
 		if (candidate == parent) {
 			return true;
 		}
+		if (candidate == null) {
+			return false;
+		}
 		ClassLoader classLoaderToCheck = candidate;
 		while (classLoaderToCheck != null) {
 			classLoaderToCheck = classLoaderToCheck.getParent();

org.springframework.beans/src/test/java/org/springframework/beans/CachedIntrospectionResultsTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * Copyright 2002-2013 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.
@@ -16,12 +16,14 @@
 
 package org.springframework.beans;
 
-import static org.junit.Assert.*;
+import java.util.ArrayList;
 
 import org.junit.Test;
+import test.beans.TestBean;
+
 import org.springframework.core.OverridingClassLoader;
 
-import test.beans.TestBean;
+import static org.junit.Assert.*;
 
 /**
  * @author Juergen Hoeller
@@ -30,7 +32,7 @@ import test.beans.TestBean;
 public final class CachedIntrospectionResultsTests {
 
 	@Test
-	public void testAcceptClassLoader() throws Exception {
+	public void acceptAndClearClassLoader() throws Exception {
 		BeanWrapper bw = new BeanWrapperImpl(TestBean.class);
 		assertTrue(bw.isWritableProperty("name"));
 		assertTrue(bw.isWritableProperty("age"));
@@ -50,4 +52,12 @@ public final class CachedIntrospectionResultsTests {
 		assertTrue(CachedIntrospectionResults.classCache.containsKey(TestBean.class));
 	}
 
+	@Test
+	public void clearClassLoaderForSystemClassLoader() throws Exception {
+		BeanUtils.getPropertyDescriptors(ArrayList.class);
+		assertTrue(CachedIntrospectionResults.classCache.containsKey(ArrayList.class));
+		CachedIntrospectionResults.clearClassLoader(ArrayList.class.getClassLoader());
+		assertFalse(CachedIntrospectionResults.classCache.containsKey(ArrayList.class));
+	}
+
 }