Added sample for invocation of JDK 8 default method on a repository.

jpa/java8/pom.xml

@@ -10,6 +10,10 @@
 
 	<artifactId>spring-data-jpa-java8</artifactId>
 	<name>Spring Data JPA - Java 8 specific features</name>
+	
+	<properties>
+		<spring-data-releasetrain.version>Evans-BUILD-SNAPSHOT</spring-data-releasetrain.version>
+	</properties>
 
 	<dependencies>
 

jpa/java8/src/main/java/example/springdata/jpa/java8/CustomerRepository.java

@@ -36,4 +36,10 @@ public interface CustomerRepository extends Repository<Customer, Long> {
 	Optional<Customer> findOne(Long id);
 
 	<S extends Customer> S save(S customer);
+
+	Optional<Customer> findByLastname(String lastname);
+
+	default Optional<Customer> findByLastname(Customer customer) {
+		return findByLastname(customer.lastname);
+	}
 }

jpa/java8/src/test/java/example/springdata/jpa/java8/Java8IntegrationTests.java

@@ -56,4 +56,14 @@ public class Java8IntegrationTests {
 		assertThat(customer.createdDate, is(notNullValue()));
 		assertThat(customer.modifiedDate, is(notNullValue()));
 	}
+
+	@Test
+	public void invokesDefaultMethod() {
+
+		Customer customer = repository.save(new Customer("Dave", "Matthews"));
+		Optional<Customer> result = repository.findByLastname(customer);
+
+		assertThat(result.isPresent(), is(true));
+		assertThat(result.get(), is(customer));
+	}
 }