implement loading by primary key

build.gradle.kts

@@ -132,6 +132,7 @@ dependencies {
     testImplementation(libs.bundles.test.common)
     testImplementation(libs.mockito.junit.jupiter)
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")
+    testCompileOnly(libs.checker.qual)
 
     integrationTestImplementation(libs.bundles.test.common)
     @Suppress("UnstableApiUsage")

gradle/libs.versions.toml

@@ -23,6 +23,7 @@ mongo-java-driver-sync = "5.3.1"
 slf4j-api = "2.0.16"
 logback-classic = "1.5.16"
 mockito = "5.16.0"
+checker-qual = "3.49.1"
 
 plugin-spotless = "7.0.2"
 plugin-errorprone = "4.1.0"
@@ -42,6 +43,7 @@ mongo-java-driver-sync = { module = "org.mongodb:mongodb-driver-sync", version.r
 sl4j-api = { module = "org.slf4j:slf4j-api", version.ref = "slf4j-api" }
 logback-classic = { module = "ch.qos.logback:logback-classic", version.ref = "logback-classic" }
 mockito-junit-jupiter = { module = "org.mockito:mockito-junit-jupiter", version.ref = "mockito" }
+checker-qual = { module = "org.checkerframework:checker-qual", version.ref = "checker-qual" }
 
 [bundles]
 test-common = ["junit-jupiter", "assertj", "logback-classic"]

src/integrationTest/java/com/mongodb/hibernate/BasicCrudIntegrationTests.java

@@ -198,6 +198,45 @@ void testDynamicUpdate() {
         }
     }
 
+    @Nested
+    class SelectTests {
+
+        @Test
+        void testGetByPrimaryKeyWithoutNullValueField() {
+            var book = new Book();
+            book.id = 1;
+            book.author = "Marcel Proust";
+            book.title = "In Search of Lost Time";
+            book.publishYear = 1913;
+
+            sessionFactoryScope.inTransaction(session -> session.persist(book));
+
+            var loadedBook = sessionFactoryScope.fromTransaction(session -> session.get(Book.class, 1));
+            assertThat(loadedBook)
+                    .isNotNull()
+                    .usingRecursiveComparison()
+                    .withStrictTypeChecking()
+                    .isEqualTo(book);
+        }
+
+        @Test
+        void testGetByPrimaryKeyWithNullValueField() {
+            var book = new Book();
+            book.id = 1;
+            book.title = "Brave New World";
+            book.publishYear = 1932;
+
+            sessionFactoryScope.inTransaction(session -> session.persist(book));
+
+            var loadedBook = sessionFactoryScope.fromTransaction(session -> session.get(Book.class, 1));
+            assertThat(loadedBook)
+                    .isNotNull()
+                    .usingRecursiveComparison()
+                    .withStrictTypeChecking()
+                    .isEqualTo(book);
+        }
+    }
+
     private static void assertCollectionContainsExactly(BsonDocument expectedDoc) {
         assertThat(mongoCollection.find()).containsExactly(expectedDoc);
     }

src/integrationTest/resources/logback-test.xml

@@ -10,7 +10,9 @@
     <logger name="org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator" level="debug" additivity="true"/>
     <logger name="org.hibernate.SQL" level="debug" additivity="true"/>
     <logger name="org.hibernate.orm.jdbc.bind" level="trace" additivity="true"/>
+    <logger name="org.hibernate.orm.jdbc.extract" level="trace" additivity="true"/>
     <logger name="org.hibernate.persister.entity" level="debug" additivity="true"/>
+    <logger name="org.hibernate.orm.sql.ast.tree" level="debug" additivity="true"/>
     <logger name="org.mongodb.driver" level="warn" additivity="true"/>
     <logger name="com.mongodb.hibernate" level="debug" additivity="true"/>
     <root level="info">