From 75e5a75da5bf95f333d359f6164f81e2f71bee5a Mon Sep 17 00:00:00 2001
From: Juergen Hoeller <juergen.hoeller@broadcom.com>
Date: Fri, 28 Mar 2025 20:46:09 +0100
Subject: [PATCH] Enforce circular reference exception within non-managed
 thread

Closes gh-34672
---
 .../support/DefaultSingletonBeanRegistry.java | 19 +++++++-
 .../annotation/BackgroundBootstrapTests.java  | 47 ++++++++++++++++++-
 2 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java b/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java
index fd88d2c44c..eea12e5ab0 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java
@@ -110,6 +110,9 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 	/** Names of beans that are currently in lenient creation. */
 	private final Set<String> singletonsInLenientCreation = new HashSet<>();
 
+	/** Map from bean name to actual creation thread for leniently created beans. */
+	private final Map<String, Thread> lenientCreationThreads = new ConcurrentHashMap<>();
+
 	/** Flag that indicates whether we're currently within destroySingletons. */
 	private volatile boolean singletonsCurrentlyInDestruction = false;
 
@@ -307,6 +310,9 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 							if (!this.singletonsInLenientCreation.contains(beanName)) {
 								break;
 							}
+							if (this.lenientCreationThreads.get(beanName) == Thread.currentThread()) {
+								throw ex;
+							}
 							try {
 								this.lenientCreationFinished.await();
 							}
@@ -344,7 +350,18 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 					// Leniently created singleton object could have appeared in the meantime.
 					singletonObject = this.singletonObjects.get(beanName);
 					if (singletonObject == null) {
-						singletonObject = singletonFactory.getObject();
+						if (locked) {
+							singletonObject = singletonFactory.getObject();
+						}
+						else {
+							this.lenientCreationThreads.put(beanName, Thread.currentThread());
+							try {
+								singletonObject = singletonFactory.getObject();
+							}
+							finally {
+								this.lenientCreationThreads.remove(beanName);
+							}
+						}
 						newSingleton = true;
 					}
 				}
diff --git a/spring-context/src/test/java/org/springframework/context/annotation/BackgroundBootstrapTests.java b/spring-context/src/test/java/org/springframework/context/annotation/BackgroundBootstrapTests.java
index 913cc863d0..bd2071f960 100644
--- a/spring-context/src/test/java/org/springframework/context/annotation/BackgroundBootstrapTests.java
+++ b/spring-context/src/test/java/org/springframework/context/annotation/BackgroundBootstrapTests.java
@@ -19,7 +19,9 @@ package org.springframework.context.annotation;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Timeout;
 
+import org.springframework.beans.factory.BeanCurrentlyInCreationException;
 import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.beans.factory.UnsatisfiedDependencyException;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.DefaultListableBeanFactory;
 import org.springframework.beans.testfixture.beans.TestBean;
@@ -29,6 +31,7 @@ import org.springframework.core.testfixture.EnabledForTestGroups;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.springframework.context.annotation.Bean.Bootstrap.BACKGROUND;
 import static org.springframework.core.testfixture.TestGroup.LONG_RUNNING;
 
@@ -85,6 +88,15 @@ class BackgroundBootstrapTests {
 		ctx.close();
 	}
 
+	@Test
+	@Timeout(5)
+	@EnabledForTestGroups(LONG_RUNNING)
+	void bootstrapWithCircularReferenceInSameThread() {
+		assertThatExceptionOfType(UnsatisfiedDependencyException.class)
+				.isThrownBy(() -> new AnnotationConfigApplicationContext(CircularReferenceInSameThreadBeanConfig.class))
+				.withRootCauseInstanceOf(BeanCurrentlyInCreationException.class);
+	}
+
 	@Test
 	@Timeout(5)
 	@EnabledForTestGroups(LONG_RUNNING)
@@ -179,7 +191,7 @@ class BackgroundBootstrapTests {
 			catch (InterruptedException ex) {
 				throw new RuntimeException(ex);
 			}
-			return new TestBean();
+			return new TestBean("testBean1");
 		}
 
 		@Bean
@@ -217,6 +229,39 @@ class BackgroundBootstrapTests {
 	}
 
 
+	@Configuration(proxyBeanMethods = false)
+	static class CircularReferenceInSameThreadBeanConfig {
+
+		@Bean
+		public TestBean testBean1(ObjectProvider<TestBean> testBean2) {
+			new Thread(testBean2::getObject).start();
+			try {
+				Thread.sleep(1000);
+			}
+			catch (InterruptedException ex) {
+				throw new RuntimeException(ex);
+			}
+			return new TestBean();
+		}
+
+		@Bean
+		public TestBean testBean2(TestBean testBean3) {
+			try {
+				Thread.sleep(2000);
+			}
+			catch (InterruptedException ex) {
+				throw new RuntimeException(ex);
+			}
+			return new TestBean();
+		}
+
+		@Bean
+		public TestBean testBean3(TestBean testBean2) {
+			return new TestBean();
+		}
+	}
+
+
 	@Configuration(proxyBeanMethods = false)
 	static class CustomExecutorBeanConfig {