From ea00ab9919040c378394b96301c9988566fb249d Mon Sep 17 00:00:00 2001
From: Andy Wilkinson <awilkinson@pivotal.io>
Date: Fri, 20 Dec 2019 15:53:08 +0000
Subject: [PATCH] Protect against NoSuchMethodError when deploying to old
 Tomcats

Fixes gh-19308
---
 .../web/embedded/TomcatWebServerFactoryCustomizer.java    | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java
index 052a13ba12..d7e6701adb 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java
@@ -186,7 +186,13 @@ public class TomcatWebServerFactoryCustomizer
 			// The internal proxies default to a white list of "safe" internal IP
 			// addresses
 			valve.setInternalProxies(tomcatProperties.getInternalProxies());
-			valve.setHostHeader(tomcatProperties.getHostHeader());
+			try {
+				valve.setHostHeader(tomcatProperties.getHostHeader());
+			}
+			catch (NoSuchMethodError ex) {
+				// Avoid failure with war deployments to Tomcat 8.5 before 8.5.44 and
+				// Tomcat 9 before 9.0.23
+			}
 			valve.setPortHeader(tomcatProperties.getPortHeader());
 			valve.setProtocolHeaderHttpsValue(tomcatProperties.getProtocolHeaderHttpsValue());
 			// ... so it's safe to add this valve by default.