From a6705d5fab69280e19ba3601da53cf476383f5fb Mon Sep 17 00:00:00 2001
From: BenchmarkingBuffalo
 <46448799+BenchmarkingBuffalo@users.noreply.github.com>
Date: Tue, 12 Aug 2025 22:11:54 +0200
Subject: [PATCH] Fail fast with explicit error message for incompatible JDK
 version

If the JDK version used to compile the software is not compatible with Java 24, the build fails fast with a hint what has gone wrong.
This check happens on the 'projectsLoaded' hook.
Fix gh-46625

Signed-off-by: BenchmarkingBuffalo <46448799+BenchmarkingBuffalo@users.noreply.github.com>
---
 settings.gradle | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/settings.gradle b/settings.gradle
index 4f2cfa7992c1..5c7cfb0aaeaf 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -44,6 +44,11 @@ rootProject.name="spring-boot-build"
 enableFeaturePreview("STABLE_CONFIGURATION_CACHE")
 
 settings.gradle.projectsLoaded {
+	ensureCompatibleJavaVersion -> {
+		if (!JavaVersion.current().isCompatibleWith(JavaVersion.toVersion(24))) {
+			throw new GradleException("Java 24 or newer is needed to compile. Java version used is ${JavaVersion.current().toString()}.")
+		}
+	}
 	develocity {
 		buildScan {
 			def toolchainVersion = settings.gradle.rootProject.findProperty('toolchainVersion')