diff --git a/data/data-jdbc-h2-kotlin/src/test/java/com/example/data/jdbc/h2/kotlin/DataJdbcTests.java b/data/data-jdbc-h2-kotlin/src/test/java/com/example/data/jdbc/h2/kotlin/DataJdbcTests.java
new file mode 100644
index 00000000..99b6c875
--- /dev/null
+++ b/data/data-jdbc-h2-kotlin/src/test/java/com/example/data/jdbc/h2/kotlin/DataJdbcTests.java
@@ -0,0 +1,39 @@
+package com.example.data.jdbc.h2.kotlin;
+
+import com.example.data.jdbc.h2.kotlin.model.Author;
+import com.example.data.jdbc.h2.kotlin.model.Book;
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.data.jdbc.DataJdbcTest;
+import org.springframework.jdbc.core.JdbcTemplate;
+import java.util.Set;
+
+@DataJdbcTest
+class DataJdbcTests {
+
+	@Autowired
+	private JdbcTemplate jdbcTemplate;
+
+	@Autowired
+	private AuthorRepository authorRepository;
+
+	@Test
+	void shouldHaveSchema() {
+		Assertions.assertThatNoException().isThrownBy(() -> jdbcTemplate.execute("SELECT * FROM author"));
+	}
+
+	@Test
+	void shouldSaveAndLoad() {
+
+		var book1 = new Book(null, "book-1");
+		var author1 = new Author(null, "author-1", Set.of(book1));
+		authorRepository.save(author1);
+		var found = authorRepository.queryFindByName("author-1");
+		Assertions.assertThat(found).isNotNull();
+		Assertions.assertThat(found.getId()).isNotNull();
+		Assertions.assertThat(found.getName()).isEqualTo("author-1");
+		Assertions.assertThat(found.getBooks()).hasSize(1);
+	}
+
+}
diff --git a/data/data-jdbc-h2-kotlin/src/test/kotlin/com/example/data/jdbc/h2/kotlin/DataJdbcTests.kt b/data/data-jdbc-h2-kotlin/src/test/kotlin/com/example/data/jdbc/h2/kotlin/DataJdbcTests.kt
deleted file mode 100644
index 925ec51f..00000000
--- a/data/data-jdbc-h2-kotlin/src/test/kotlin/com/example/data/jdbc/h2/kotlin/DataJdbcTests.kt
+++ /dev/null
@@ -1,39 +0,0 @@
-package com.example.data.jdbc.h2.kotlin
-
-import com.example.data.jdbc.h2.kotlin.model.Author
-import com.example.data.jdbc.h2.kotlin.model.Book
-import org.assertj.core.api.Assertions
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import org.springframework.beans.factory.annotation.Autowired
-import org.springframework.boot.test.autoconfigure.data.jdbc.DataJdbcTest
-import org.springframework.jdbc.core.JdbcTemplate
-import java.util.Set
-
-@DataJdbcTest
-class DataJdbcTests {
-	@Autowired
-	private lateinit var jdbcTemplate: JdbcTemplate
-
-	@Autowired
-	private lateinit var authorRepository: AuthorRepository
-
-	@Test
-	fun shouldHaveSchema() {
-		Assertions.assertThatCode { jdbcTemplate.execute("SELECT * FROM author") }
-			.doesNotThrowAnyException()
-	}
-
-	@Test
-	fun shouldSaveAndLoad() {
-		val book1 = Book(null, "book-1")
-		val author1 = Author(null, "author-1", Set.of(book1))
-		authorRepository.save(author1)
-		val found = authorRepository.queryFindByName("author-1")
-		assertThat(found).isNotNull()
-		checkNotNull(found)
-		assertThat(found.id).isNotNull()
-		assertThat(found.name).isEqualTo("author-1")
-		assertThat(found.books).hasSize(1)
-	}
-}