[BAEL-4601] How to convert a Hibernate proxy to a real entity object

* Adds Domain Models * Adds Integration Tests
2021-01-05 01:32:23 +08:00
parent f63058acb6
commit 6daa38007c
6 changed files with 257 additions and 0 deletions
@@ -0,0 +1,75 @@
+package com.baeldung.jpa.hibernateunproxy;
+
+import org.hibernate.Hibernate;
+import org.hibernate.proxy.HibernateProxy;
+import org.junit.Assert;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+import java.math.BigDecimal;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class HibernateProxyIntegrationTest {
+
+    private static EntityManager entityManager;
+
+    @BeforeAll
+    public static void setup() {
+        EntityManagerFactory factory = Persistence.createEntityManagerFactory("jpa-h2-hibernate-unproxy");
+        entityManager = factory.createEntityManager();
+        populateH2DB();
+    }
+
+    @Test
+    public void givenPaymentReceipt_whenAccessingPayment_thenVerifyType() {
+        PaymentReceipt paymentReceipt = entityManager.find(PaymentReceipt.class, 3L);
+        Assert.assertEquals(true, paymentReceipt.getPayment() instanceof HibernateProxy);
+    }
+
+    @Test
+    public void givenWebUserProxy_whenCreatingPayment_thenExecuteSingleStatement() {
+        entityManager.getTransaction().begin();
+
+        WebUser webUser = entityManager.getReference(WebUser.class, 1L);
+        Payment payment = new CreditCardPayment(new BigDecimal(100), webUser, "CN-1234");
+        entityManager.persist(payment);
+
+        entityManager.getTransaction().commit();
+        Assert.assertEquals(true, webUser instanceof HibernateProxy);
+    }
+
+    @Test
+    public void givenPaymentReceipt_whenCastingPaymentToConcreteClass_thenThrowClassCastException() {
+        PaymentReceipt paymentReceipt = entityManager.find(PaymentReceipt.class, 3L);
+        assertThrows(ClassCastException.class, () -> {
+            CreditCardPayment creditCardPayment = (CreditCardPayment) paymentReceipt.getPayment();
+        });
+    }
+
+    @Test
+    public void givenPaymentReceipt_whenPaymentIsUnproxied_thenReturnRealEntityObject() {
+        PaymentReceipt paymentReceipt = entityManager.find(PaymentReceipt.class, 3L);
+        Assert.assertEquals(true, Hibernate.unproxy(paymentReceipt.getPayment()) instanceof CreditCardPayment);
+    }
+
+    private static void populateH2DB() {
+        entityManager.getTransaction().begin();
+
+        WebUser webUser = new WebUser("name");
+        entityManager.persist(webUser);
+
+        Payment payment = new CreditCardPayment(new BigDecimal(100), webUser, "CN-1234");
+        entityManager.persist(payment);
+
+        PaymentReceipt receipt = new PaymentReceipt(payment);
+        entityManager.persist(receipt);
+
+        entityManager.getTransaction().commit();
+        entityManager.clear();
+    }
+
+}