diff --git a/build.gradle b/build.gradle
index 24be2186d0..e597ed582e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -60,7 +60,8 @@ configure(allprojects) { project ->
 				entry 'aspectjtools'
 				entry 'aspectjweaver'
 			}
-			dependencySet(group: 'org.codehaus.groovy', version: '2.5.9') {
+			// If customJavaHome has been set, we assume we need Groovy 3.0 for testing purposes.
+			dependencySet(group: 'org.codehaus.groovy', version: System.getProperty("customJavaHome") ?  '3.0.0-rc-3' : '2.5.9') {
 				entry 'groovy'
 				entry 'groovy-jsr223'
 				entry 'groovy-templates'
@@ -305,6 +306,7 @@ configure([rootProject] + javaProjects) { project ->
 	apply plugin: "java-test-fixtures"
 	apply plugin: "checkstyle"
 	apply plugin: 'org.springframework.build.compile'
+	apply from: "${rootDir}/gradle/custom-java-home.gradle"
 	apply from: "${rootDir}/gradle/ide.gradle"
 
 	pluginManager.withPlugin("kotlin") {
diff --git a/gradle/build-scan-user-data.gradle b/gradle/build-scan-user-data.gradle
index d4f483d66f..c9463e7f33 100644
--- a/gradle/build-scan-user-data.gradle
+++ b/gradle/build-scan-user-data.gradle
@@ -4,6 +4,8 @@ tagCiOrLocal()
 addCiMetadata()
 addGitMetadata()
 addTestTaskMetadata()
+addCustomJavaHomeMetadata()
+addCustomJavaSourceVersionMetadata()
 
 void tagOs() {
 	buildScan.tag System.getProperty('os.name')
@@ -60,6 +62,20 @@ void addTestTaskMetadata() {
 	}
 }
 
+void addCustomJavaHomeMetadata() {
+	def customJavaHome = System.getProperty("customJavaHome")
+	if (customJavaHome) {
+		buildScan.value "Custom JAVA_HOME", customJavaHome
+	}
+}
+
+void addCustomJavaSourceVersionMetadata() {
+	def customJavaSourceVersion = System.getProperty("customJavaSourceVersion")
+	if (customJavaSourceVersion) {
+		buildScan.value "Custom Java Source Version", customJavaSourceVersion
+	}
+}
+
 boolean isCi() {
 	isBamboo()
 }
diff --git a/gradle/custom-java-home.gradle b/gradle/custom-java-home.gradle
new file mode 100644
index 0000000000..39d2619e9a
--- /dev/null
+++ b/gradle/custom-java-home.gradle
@@ -0,0 +1,87 @@
+// -----------------------------------------------------------------------------
+//
+// This script adds support for the following two JVM system properties
+// that control the build for alternative JDKs (i.e., a JDK other than
+// the one used to launch the Gradle process).
+//
+// - customJavaHome: absolute path to the alternate JDK installation to
+//     use to compile Java code and execute tests. Setting this system
+//     property causes Groovy 3.0 RC3 to be used instead of 2.5.x. This
+//     system property is also used in spring-oxm.gradle to determine
+//     whether JiBX is supported.
+//
+// - customJavaSourceVersion: Java version supplied to the `--release`
+//     command line flag to control the Java source and target
+//     compatibility version. Supported versions include 9 or higher.
+//     Do not set this system property if Java 8 should be used.
+//
+// Examples:
+// 	
+// ./gradlew -DcustomJavaHome=/Library/Java/JavaVirtualMachines/jdk-14.jdk/Contents/Home test
+//
+// ./gradlew --no-build-cache -DcustomJavaHome=/Library/Java/JavaVirtualMachines/jdk-14.jdk/Contents/Home test
+//
+// ./gradlew -DcustomJavaHome=/Library/Java/JavaVirtualMachines/jdk-14.jdk/Contents/Home -DcustomJavaSourceVersion=14 test
+//
+// -----------------------------------------------------------------------------
+
+import org.gradle.internal.os.OperatingSystem
+// import org.jetbrains.kotlin.gradle.dsl.KotlinJvmCompile
+
+def customJavaHome = System.getProperty("customJavaHome")
+
+if (customJavaHome) {
+	def javacExecutable = customJavaHome + "/bin/javac"
+	def javaExecutable = customJavaHome + "/bin/java"
+	if (OperatingSystem.current().isWindows()) {
+		javacExecutable += ".exe"
+		javaExecutable += ".exe"
+	}
+
+	def customJavaSourceVersion = System.getProperty("customJavaSourceVersion")
+
+	tasks.withType(JavaCompile) {
+		logger.info("Java compiler for " + it.name + " task in " + project.name + ": " + javacExecutable)
+		doFirst {
+			// Avoid compiler warnings for non-existing path entries
+			classpath = classpath.filter { it.exists() }
+		}
+		options.fork = true
+		options.forkOptions.executable = javacExecutable
+		options.compilerArgs -= "-Werror"
+		if (customJavaSourceVersion) {
+			options.compilerArgs += [ "--release", customJavaSourceVersion]
+			inputs.property("customJavaSourceVersion", customJavaSourceVersion)
+		}
+		inputs.property("customJavaHome", customJavaHome)
+	}
+
+	tasks.withType(GroovyCompile) {
+		logger.info("Java compiler for " + it.name + " task in " + project.name + ": " + javacExecutable)
+		options.fork = true
+		options.forkOptions.executable = javacExecutable
+		if (customJavaSourceVersion) {
+			options.compilerArgs += [ "--release", customJavaSourceVersion]
+			inputs.property("customJavaSourceVersion", customJavaSourceVersion)
+		}
+		inputs.property("customJavaHome", customJavaHome)
+	}
+
+	/*
+	tasks.withType(KotlinJvmCompile) {
+		logger.info("Java home for " + it.name + " task in " + project.name + ": " + customJavaHome)
+		kotlinOptions.jdkHome = customJavaHome
+		inputs.property("customJavaHome", customJavaHome)
+	}
+	*/
+
+	tasks.withType(Test) {
+		logger.info("Java executable for " + it.name + " task in " + project.name + ": " + javaExecutable)
+		executable = javaExecutable
+		inputs.property("customJavaHome", customJavaHome)
+		if (customJavaSourceVersion) {
+			inputs.property("customJavaSourceVersion", customJavaSourceVersion)
+		}
+	}
+
+}
diff --git a/spring-oxm/spring-oxm.gradle b/spring-oxm/spring-oxm.gradle
index 530245c126..9d23276d22 100644
--- a/spring-oxm/spring-oxm.gradle
+++ b/spring-oxm/spring-oxm.gradle
@@ -74,8 +74,9 @@ dependencies {
 	testRuntime("com.sun.xml.bind:jaxb-impl")
 }
 
-// JiBX compiler is currently not compatible with JDK 9+
-if (JavaVersion.current() == JavaVersion.VERSION_1_8) {
+// JiBX compiler is currently not compatible with JDK 9+.
+// If customJavaHome has been set, we assume the custom JDK version is 9+.
+if ((JavaVersion.current() == JavaVersion.VERSION_1_8) && !System.getProperty("customJavaSourceVersion")) {
 	compileTestJava {
 		def bindingXml = "${projectDir}/src/test/resources/org/springframework/oxm/jibx/binding.xml"