DefaultSingletonBeanRegistry's isDependent defensively checks for circular recursion

Issue: SPR-10787
(cherry picked from commit 15d3b88)

Author: jhoeller

spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java

@@ -18,6 +18,7 @@
 
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
@@ -415,17 +416,30 @@ public void registerDependentBean(String beanName, String dependentBeanName) {
 	 * dependent on the given bean or on any of its transitive dependencies.
 	 * @param beanName the name of the bean to check
 	 * @param dependentBeanName the name of the dependent bean
+	 * @since 4.0
 	 */
 	protected boolean isDependent(String beanName, String dependentBeanName) {
-		Set<String> dependentBeans = this.dependentBeanMap.get(beanName);
+		return isDependent(beanName, dependentBeanName, null);
+	}
+
+	private boolean isDependent(String beanName, String dependentBeanName, Set<String> alreadySeen) {
+		String canonicalName = canonicalName(beanName);
+		if (alreadySeen != null && alreadySeen.contains(beanName)) {
+			return false;
+		}
+		Set<String> dependentBeans = this.dependentBeanMap.get(canonicalName);
 		if (dependentBeans == null) {
 			return false;
 		}
 		if (dependentBeans.contains(dependentBeanName)) {
 			return true;
 		}
 		for (String transitiveDependency : dependentBeans) {
-			if (isDependent(transitiveDependency, dependentBeanName)) {
+			if (alreadySeen == null) {
+				alreadySeen = new HashSet<String>();
+			}
+			alreadySeen.add(beanName);
+			if (isDependent(transitiveDependency, dependentBeanName, alreadySeen)) {
 				return true;
 			}
 		}

spring-beans/src/test/java/org/springframework/beans/factory/SharedBeanRegistryTests.java renamed to spring-beans/src/test/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistryTests.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.
@@ -14,24 +14,23 @@
  * limitations under the License.
  */
 
-package org.springframework.beans.factory;
-
-import static org.junit.Assert.*;
-
-import java.util.Arrays;
+package org.springframework.beans.factory.support;
 
 import org.junit.Test;
+
 import org.springframework.beans.BeansException;
-import org.springframework.beans.factory.support.DefaultSingletonBeanRegistry;
+import org.springframework.beans.factory.ObjectFactory;
 import org.springframework.tests.sample.beans.DerivedTestBean;
 import org.springframework.tests.sample.beans.TestBean;
 
+import static org.junit.Assert.*;
+
 /**
  * @author Juergen Hoeller
  * @author Chris Beams
  * @since 04.07.2006
  */
-public final class SharedBeanRegistryTests {
+public class DefaultSingletonBeanRegistryTests {
 
 	@Test
 	public void testSingletons() {
@@ -52,9 +51,10 @@ public Object getObject() throws BeansException {
 		assertSame(tb, beanRegistry.getSingleton("tb"));
 		assertSame(tb2, beanRegistry.getSingleton("tb2"));
 		assertEquals(2, beanRegistry.getSingletonCount());
-		assertEquals(2, beanRegistry.getSingletonNames().length);
-		assertTrue(Arrays.asList(beanRegistry.getSingletonNames()).contains("tb"));
-		assertTrue(Arrays.asList(beanRegistry.getSingletonNames()).contains("tb2"));
+		String[] names = beanRegistry.getSingletonNames();
+		assertEquals(2, names.length);
+		assertEquals("tb", names[0]);
+		assertEquals("tb2", names[1]);
 
 		beanRegistry.destroySingletons();
 		assertEquals(0, beanRegistry.getSingletonCount());
@@ -72,8 +72,9 @@ public void testDisposableBean() {
 
 		assertSame(tb, beanRegistry.getSingleton("tb"));
 		assertEquals(1, beanRegistry.getSingletonCount());
-		assertEquals(1, beanRegistry.getSingletonNames().length);
-		assertTrue(Arrays.asList(beanRegistry.getSingletonNames()).contains("tb"));
+		String[] names = beanRegistry.getSingletonNames();
+		assertEquals(1, names.length);
+		assertEquals("tb", names[0]);
 		assertFalse(tb.wasDestroyed());
 
 		beanRegistry.destroySingletons();
@@ -82,4 +83,22 @@ public void testDisposableBean() {
 		assertTrue(tb.wasDestroyed());
 	}
 
+	@Test
+	public void testDependentRegistration() {
+		DefaultSingletonBeanRegistry beanRegistry = new DefaultSingletonBeanRegistry();
+
+		beanRegistry.registerDependentBean("a", "b");
+		beanRegistry.registerDependentBean("b", "c");
+		beanRegistry.registerDependentBean("c", "b");
+		assertTrue(beanRegistry.isDependent("a", "b"));
+		assertTrue(beanRegistry.isDependent("b", "c"));
+		assertTrue(beanRegistry.isDependent("c", "b"));
+		assertTrue(beanRegistry.isDependent("a", "c"));
+		assertFalse(beanRegistry.isDependent("c", "a"));
+		assertFalse(beanRegistry.isDependent("b", "a"));
+		assertFalse(beanRegistry.isDependent("a", "a"));
+		assertTrue(beanRegistry.isDependent("b", "b"));
+		assertTrue(beanRegistry.isDependent("c", "c"));
+	}
+
 }