BAEL-2477

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/customer/Customer.java

@@ -0,0 +1,37 @@
+package com.baeldung.customer;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+@Entity
+public class Customer {
+
+    @Id
+    @GeneratedValue
+    private long id;
+    private String name;
+    private String email;
+
+    public Customer(String name, String email) {
+        this.name = name;
+        this.email = email;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+}

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/customer/CustomerRepository.java

@@ -0,0 +1,18 @@
+package com.baeldung.customer;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
+
+public interface CustomerRepository extends JpaRepository<Customer, Long> {
+
+    List<Customer> findByName(String name);
+
+    List<Customer> findByNameAndEmail(String name, String email);
+
+    @Query("SELECT c FROM Customer c WHERE (:name is null or c.name = :name) and (:email is null or c.email = :email)")
+    List<Customer> findCustomerByNameAndEmail(@Param("name") String name, @Param("email") String email);
+
+}

persistence-modules/spring-data-jpa/src/test/java/com/baeldung/customer/CustomerRepositoryIntegrationTest.java

@@ -0,0 +1,66 @@
+package com.baeldung.customer;
+
+import com.baeldung.config.PersistenceConfiguration;
+import com.baeldung.config.PersistenceProductConfiguration;
+import com.baeldung.config.PersistenceUserConfiguration;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+
+@DataJpaTest(excludeAutoConfiguration = { PersistenceConfiguration.class, PersistenceUserConfiguration.class, PersistenceProductConfiguration.class })
+@RunWith(SpringRunner.class)
+public class CustomerRepositoryIntegrationTest {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    @Autowired
+    private CustomerRepository repository;
+
+    @Before
+    public void before() {
+        entityManager.persist(new Customer("A", "A@example.com"));
+        entityManager.persist(new Customer("D", null));
+        entityManager.persist(new Customer("D", "D@example.com"));
+    }
+
+    @Test
+    public void givenQueryMethod_whenEmailIsNull_thenFoundByNullEmail() {
+        List<Customer> customers = repository.findByNameAndEmail("D", null);
+
+        assertEquals(1, customers.size());
+        Customer actual = customers.get(0);
+
+        assertEquals(null, actual.getEmail());
+        assertEquals("D", actual.getName());
+    }
+
+    @Test
+    public void givenQueryMethod_whenEmailIsAbsent_thenIgnoreEmail() {
+        List<Customer> customers = repository.findByName("D");
+
+        assertEquals(2, customers.size());
+    }
+
+    @Test
+    public void givenQueryAnnotation_whenEmailIsNull_thenIgnoreEmail() {
+        List<Customer> customers = repository.findCustomerByNameAndEmail("D", null);
+
+        assertEquals(2, customers.size());
+    }
+
+    @After
+    public void cleanUp() {
+        repository.deleteAll();
+    }
+}