From 535050ad483990f36c73e037a900b3e848e75a82 Mon Sep 17 00:00:00 2001
From: Andy Wilkinson <wilkinsona@vmware.com>
Date: Tue, 19 Jan 2021 11:28:34 +0000
Subject: [PATCH] Automatically register HttpSessionIdListener's with the
 servlet context

Closes gh-24879
---
 .../ServletListenerRegistrationBean.java      |  5 +++-
 .../ServletContextInitializerBeansTests.java  | 25 ++++++++++++++++++-
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletListenerRegistrationBean.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletListenerRegistrationBean.java
index ebee46669d..f8f7896334 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletListenerRegistrationBean.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletListenerRegistrationBean.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -27,6 +27,7 @@ import javax.servlet.ServletContextListener;
 import javax.servlet.ServletRequestAttributeListener;
 import javax.servlet.ServletRequestListener;
 import javax.servlet.http.HttpSessionAttributeListener;
+import javax.servlet.http.HttpSessionIdListener;
 import javax.servlet.http.HttpSessionListener;
 
 import org.springframework.util.Assert;
@@ -44,6 +45,7 @@ import org.springframework.util.ClassUtils;
  * <li>{@link ServletRequestListener}</li>
  * <li>{@link ServletRequestAttributeListener}</li>
  * <li>{@link HttpSessionAttributeListener}</li>
+ * <li>{@link HttpSessionIdListener}</li>
  * <li>{@link HttpSessionListener}</li>
  * <li>{@link ServletContextListener}</li>
  * </ul>
@@ -63,6 +65,7 @@ public class ServletListenerRegistrationBean<T extends EventListener> extends Re
 		types.add(ServletRequestListener.class);
 		types.add(ServletRequestAttributeListener.class);
 		types.add(HttpSessionAttributeListener.class);
+		types.add(HttpSessionIdListener.class);
 		types.add(HttpSessionListener.class);
 		types.add(ServletContextListener.class);
 		SUPPORTED_TYPES = Collections.unmodifiableSet(types);
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/ServletContextInitializerBeansTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/ServletContextInitializerBeansTests.java
index a1de503506..ef5c1226d6 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/ServletContextInitializerBeansTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/ServletContextInitializerBeansTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -24,6 +24,7 @@ import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpSessionIdListener;
 
 import org.junit.jupiter.api.Test;
 
@@ -70,6 +71,17 @@ class ServletContextInitializerBeansTests {
 		assertThat(initializerBeans.iterator()).toIterable().hasOnlyElementsOfType(TestServletContextInitializer.class);
 	}
 
+	@Test
+	void whenAnHttpSessionIdListenerBeanIsDefinedThenARegistrationBeanIsCreatedForIt() {
+		load(HttpSessionIdListenerConfiguration.class);
+		ServletContextInitializerBeans initializerBeans = new ServletContextInitializerBeans(
+				this.context.getBeanFactory());
+		assertThat(initializerBeans).hasSize(1);
+		assertThat(initializerBeans).first().isInstanceOf(ServletListenerRegistrationBean.class)
+				.extracting(ServletListenerRegistrationBean.class::cast)
+				.extracting(ServletListenerRegistrationBean::getListener).isInstanceOf(HttpSessionIdListener.class);
+	}
+
 	private void load(Class<?>... configuration) {
 		this.context = new AnnotationConfigApplicationContext(configuration);
 	}
@@ -109,6 +121,17 @@ class ServletContextInitializerBeansTests {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	static class HttpSessionIdListenerConfiguration {
+
+		@Bean
+		HttpSessionIdListener httpSessionIdListener() {
+			return (event, oldId) -> {
+			};
+		}
+
+	}
+
 	static class TestServlet extends HttpServlet implements ServletContextInitializer {
 
 		@Override