From fd16ae78424bfce31439cc0fc67005cf7d14dba3 Mon Sep 17 00:00:00 2001
From: Zisis Pavloudis <25851168+zpavloudis@users.noreply.github.com>
Date: Mon, 28 Aug 2023 20:22:32 +0300
Subject: [PATCH 1/2] Unwrap a validator instance of specified type contained
 in SpringValidatorAdapter

See gh-37081.
---
 .../validation/ValidatorAdapter.java            | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
index 84bd614b1838..7d8cca93d5c3 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
@@ -39,6 +39,7 @@
  *
  * @author Stephane Nicoll
  * @author Phillip Webb
+ * @author Zisis Pavloudis
  * @since 2.0.0
  */
 public class ValidatorAdapter implements SmartValidator, ApplicationContextAware, InitializingBean, DisposableBean {
@@ -153,4 +154,20 @@ private static Validator wrap(Validator validator, boolean existingBean) {
 		return validator;
 	}
 
+	@Override
+	@SuppressWarnings("unchecked")
+	public <T> T unwrap(Class<T> type) {
+		if (this.target == null) {
+			return null;
+		}
+		if (type.isAssignableFrom(this.target.getClass())) {
+			if (this.target instanceof SpringValidatorAdapter adapter) {
+				return adapter.unwrap(type);
+			}
+			return (T) this.target;
+		}
+
+		throw new ValidationException("Cannot unwrap to " + type);
+	}
+
 }

From d0b461786cbcc341d534e46e228f21e9783e308b Mon Sep 17 00:00:00 2001
From: Zisis Pavloudis <25851168+zpavloudis@users.noreply.github.com>
Date: Tue, 5 Sep 2023 01:11:12 +0300
Subject: [PATCH 2/2] Polish "Unwrap a validator instance of specified type
 contained in SpringValidatorAdapter"

See gh-37081.
---
 .../autoconfigure/validation/ValidatorAdapter.java   |  5 +----
 .../validation/ValidatorAdapterTests.java            | 12 ++++++++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
index 7d8cca93d5c3..9e175774017c 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapter.java
@@ -157,9 +157,6 @@ private static Validator wrap(Validator validator, boolean existingBean) {
 	@Override
 	@SuppressWarnings("unchecked")
 	public <T> T unwrap(Class<T> type) {
-		if (this.target == null) {
-			return null;
-		}
 		if (type.isAssignableFrom(this.target.getClass())) {
 			if (this.target instanceof SpringValidatorAdapter adapter) {
 				return adapter.unwrap(type);
@@ -167,7 +164,7 @@ public <T> T unwrap(Class<T> type) {
 			return (T) this.target;
 		}
 
-		throw new ValidationException("Cannot unwrap to " + type);
+		throw new IllegalArgumentException("Cannot unwrap " + this.target + " to " + type.getName());
 	}
 
 }
diff --git a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapterTests.java b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapterTests.java
index bf57084b98ef..2230b94d612f 100644
--- a/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapterTests.java
+++ b/spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/validation/ValidatorAdapterTests.java
@@ -18,7 +18,10 @@
 
 import java.util.HashMap;
 
+import jakarta.validation.Validator;
 import jakarta.validation.constraints.Min;
+import org.hibernate.validator.HibernateValidator;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.boot.test.context.FilteredClassLoader;
@@ -91,6 +94,15 @@ void wrapperWhenValidationProviderNotPresentShouldNotThrowException() {
 			.run((context) -> ValidatorAdapter.get(context, null));
 	}
 
+	@Test
+	void unwrapValidatorInstanceOfJakartaTypeAndExceptionThrownWhenTypeNotSupported() {
+		this.contextRunner.withUserConfiguration(LocalValidatorFactoryBeanConfig.class).run((context) -> {
+			ValidatorAdapter wrapper = context.getBean(ValidatorAdapter.class);
+			assertThat(wrapper.unwrap(Validator.class)).isInstanceOf(Validator.class);
+			Assertions.assertThrows(IllegalArgumentException.class, () -> wrapper.unwrap(HibernateValidator.class));
+		});
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	static class LocalValidatorFactoryBeanConfig {