Null arguments now get wrapped in a TypedParameterValue for Hibernate.

This avoids problems where a JDBC driver fails to determine the correct type for such values.

Closes #2370
Original pull request #2461

Author: heowc

Diff for: src/main/java/org/springframework/data/jpa/repository/query/AbstractJpaQuery.java

@@ -60,6 +60,7 @@
  * @author Nicolas Cirigliano
  * @author Jens Schauder
  * @author Сергей Цыпанов
+ * @author Wonchul Heo
  */
 public abstract class AbstractJpaQuery implements RepositoryQuery {
 
@@ -151,13 +152,21 @@ public Object execute(Object[] parameters) {
 	@Nullable
 	private Object doExecute(JpaQueryExecution execution, Object[] values) {
 
-		JpaParametersParameterAccessor accessor = new JpaParametersParameterAccessor(method.getParameters(), values);
+		JpaParametersParameterAccessor accessor = obtainParameterAccessor(values);
 		Object result = execution.execute(this, accessor);
 
 		ResultProcessor withDynamicProjection = method.getResultProcessor().withDynamicProjection(accessor);
 		return withDynamicProjection.processResult(result, new TupleConverter(withDynamicProjection.getReturnedType()));
 	}
 
+	private JpaParametersParameterAccessor obtainParameterAccessor(Object[] values) {
+		if (provider == PersistenceProvider.HIBERNATE) {
+			return new HibernateJpaParametersParameterAccessor(method.getParameters(), values, em);
+		} else {
+			return new JpaParametersParameterAccessor(method.getParameters(), values);
+		}
+	}
+
 	protected JpaQueryExecution getExecution() {
 
 		JpaQueryExecution execution = this.execution.getNullable();

Diff for: src/main/java/org/springframework/data/jpa/repository/query/HibernateJpaParametersParameterAccessor.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2017-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.jpa.repository.query;
+
+import javax.persistence.EntityManager;
+
+import org.hibernate.Session;
+import org.hibernate.TypeHelper;
+import org.hibernate.jpa.TypedParameterValue;
+import org.hibernate.type.Type;
+import org.springframework.data.repository.query.Parameter;
+import org.springframework.data.repository.query.Parameters;
+import org.springframework.data.repository.query.ParametersParameterAccessor;
+
+/**
+ * {@link org.springframework.data.repository.query.ParameterAccessor} based on an {@link Parameters} instance.
+ * In addition to the {@link JpaParametersParameterAccessor} functions, the bindable value is provided by
+ * fetching the method type when there is null.
+ *
+ * @author Wonchul Heo
+ */
+public class HibernateJpaParametersParameterAccessor extends JpaParametersParameterAccessor {
+
+	private final TypeHelper typeHelper;
+
+	/**
+	 * Creates a new {@link ParametersParameterAccessor}.
+	 *
+	 * @param parameters must not be {@literal null}.
+	 * @param values must not be {@literal null}.
+	 * @param em must not be {@literal null}.
+	 */
+	HibernateJpaParametersParameterAccessor(Parameters<?, ?> parameters, Object[] values, EntityManager em) {
+		super(parameters, values);
+		Session session = em.unwrap(Session.class);
+		this.typeHelper = session.getSessionFactory().getTypeHelper();
+	}
+
+	public Object getValue(Parameter parameter) {
+		Object value = super.getValue(parameter.getIndex());
+		if (value == null) {
+			Type type = typeHelper.basic(parameter.getType());
+			if (type == null) {
+				return null;
+			}
+			return new TypedParameterValue(type, null);
+		}
+		return value;
+	}
+
+	@Override
+	public Object[] getValues() {
+		return super.getValues();
+	}
+}

Diff for: src/test/java/org/springframework/data/jpa/repository/query/JpaParametersParameterAccessorTests.java

@@ -0,0 +1,86 @@
+package org.springframework.data.jpa.repository.query;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.isNull;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+import java.lang.reflect.Method;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import javax.persistence.Query;
+
+import org.hibernate.jpa.TypedParameterValue;
+import org.hibernate.type.StandardBasicTypes;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.springframework.data.jpa.domain.sample.User;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+
+/**
+ * Unit test for {@link JpaParametersParameterAccessor}.
+ *
+ * @author Wonchul Heo
+ */
+@ExtendWith(SpringExtension.class)
+@ContextConfiguration("classpath:infrastructure.xml")
+class JpaParametersParameterAccessorTests {
+
+    @PersistenceContext
+    private EntityManager em;
+    private Query query;
+
+    @BeforeEach
+    void setUp() {
+        query = mock(Query.class);
+    }
+
+    @Test // GH-2370
+    void createsJpaParametersParameterAccessor() throws Exception {
+
+        Method withNativeQuery = SampleRepository.class.getMethod("withNativeQuery", Integer.class);
+        Object[] values = { null };
+        JpaParameters parameters = new JpaParameters(withNativeQuery);
+        JpaParametersParameterAccessor accessor = new JpaParametersParameterAccessor(parameters, values);
+
+        bind(parameters, accessor);
+
+        verify(query).setParameter(eq(1), isNull());
+    }
+
+    @Test // GH-2370
+    void createsHibernateParametersParameterAccessor() throws Exception {
+
+        Method withNativeQuery = SampleRepository.class.getMethod("withNativeQuery", Integer.class);
+        Object[] values = { null };
+        JpaParameters parameters = new JpaParameters(withNativeQuery);
+        JpaParametersParameterAccessor accessor =
+                new HibernateJpaParametersParameterAccessor(parameters, values, em);
+
+        bind(parameters, accessor);
+
+        ArgumentCaptor<TypedParameterValue> captor = ArgumentCaptor.forClass(TypedParameterValue.class);
+        verify(query).setParameter(eq(1), captor.capture());
+        TypedParameterValue captorValue = captor.getValue();
+        assertThat(captorValue.getType()).isEqualTo(StandardBasicTypes.INTEGER);
+        assertThat(captorValue.getValue()).isNull();
+    }
+
+    private void bind(JpaParameters parameters, JpaParametersParameterAccessor accessor) {
+        ParameterBinderFactory.createBinder(parameters).bind(QueryParameterSetter.BindableQuery.from(query),
+                                                             accessor,
+                                                             QueryParameterSetter.ErrorHandling.LENIENT);
+    }
+
+    interface SampleRepository {
+        @org.springframework.data.jpa.repository.Query(
+                value = "select 1 from user where age = :age",
+                nativeQuery = true)
+        User withNativeQuery(Integer age);
+    }
+}