1. Spring 3.1
© Zenika 2011 Spring 3.1 1

2. Speaker's qualifications
• Arnaud Cogoluègnes
• Consultant with Zenika
• Has been using Spring since 2005
• SpringSource certified trainer
• Co-author:
• Spring par la pratique, 2nd edition
• Spring Dynamic Modules in Action
• Spring Batch in Action
© Zenika 2011 Spring 3.1 2

3. Agenda
• History
• Environment
• Java configuration
• Spring JPA
• Cache abstraction
• Spring MVC improvements
© Zenika 2011 Spring 3.1 3

4. History
• v. 0.9 : june 2003 (foundations)
• v. 1.0 : march 2004
• v. 1.1 : september 2004
• v. 1.2 : may 2005
• v. 2.0 : october 2006 (XML namespaces)
• v. 2.5 : november 2007 (annotations)
• v. 3.0 : décember 2009 (Java config, SpEL, REST)
© Zenika 2011 Spring 3.1 4

5. Environment
• Inside the application context
Environment
Property Source Profile
Property Source Profile
© Zenika 2011 Spring 3.1 5

6. Environment / Property Source
• Do you know this?
<context:property-placeholder location="database.properties"/>
<bean id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="${db.driver}" />
<property name="url" value="jdbc:${db.url}" />
<property name="username" value="${db.user}" />
<property name="password" value="${db.password}" />
</bean>
database.properties
db.driver=org.h2.driver
db.url=jdbc:h2:mem:db1
db.user=sa
db.password=
© Zenika 2011 Spring 3.1 6

7. Environment / Property Source
• Spring 3.1 introduces an abstraction for property sources
• But what is a PropertySource anyway?
db.driver=org.h2.driver
db.url=jdbc:h2:mem:db1
Property Source = db.user=sa
db.password=
© Zenika 2011 Spring 3.1 7

8. Environment / PropertySource
• Where do PropertySources come from?
System and environment
variables
Properties files Properties
PropertySource
Resource
PropertySource
Servlet context and config
JNDI ServletContext/Config
PropertySource
Jndi
PropertySource
© Zenika 2011 Spring 3.1 8

9. Environment / Property Source
• How to refer to PropertySource?
<bean id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClass" value="${db.driver}"/>
<property name="jdbcUrl" value="${db.url}"/>
<property name="username" value="${db.user}"/>
<property name="password" value="${db.password}"/>
</bean>
© Zenika 2011 Spring 3.1 9

10. Environment / Property Source
• How to refer to PropertySource?
@Configuration
public class DatabaseConfiguration {
@Value("${db.driver}") private String driver;
@Value("${db.url}") private String url;
@Value("${db.user}") private String user;
@Value("${db.password}") private String password;
@Bean public DataSource dataSource() {
// creates DataSource
return dataSource;
}
}
© Zenika 2011 Spring 3.1 10

11. Environment / PropertySource
• How to define a PropertySource ?
<context:property-placeholder
location="classpath:application.properties" />
© Zenika 2011 Spring 3.1 11

12. Environment / PropertySource
• How to define a PropertySource ?
<context:property-placeholder
properties-ref="applicationProperties" />
<util:properties id="applicationProperties">
<prop key="db.driver">org.h2.Driver</prop>
<prop key="db.url">jdbc:h2:mem:db1</prop>
<prop key="db.user">sa</prop>
<prop key="db.password"></prop>
</util:properties>
© Zenika 2011 Spring 3.1 12

13. Environment / PropertySource
• How to define a PropertySource ?
<context-param>
<param-name>contextInitializerClasses</param-name>
<param-value>com.zenika.SomeInitializer</param-value>
</context-param>
public class SomeInitializer
implements ApplicationContextInitializer
<ConfigurableApplicationContext> {
public void initialize(
ConfigurableApplicationContext ctx) {
PropertySource ps = ...
ctx.getEnvironment().getPropertySources().addFirst(ps);
}
}
© Zenika 2011 Spring 3.1 13

14. Environment / PropertySource
• Unified way to deal with properties
• More flexible than simple property placeholder
• Configurable programmatically, useful for test configs
• Part of the new Environment abstraction
© Zenika 2011 Spring 3.1 14

15. Environment / Profile
Environment
Property Source Profile
Property Source Profile
© Zenika 2011 Spring 3.1 15

16. Environment / Profile
Application Context
Service Repository
"dev" profile "prod" profile
Datasource Datasource
© Zenika 2011 Spring 3.1 16

17. Environment / Profile
• Different beans for different environments
<bean class="com.zenika.ContactDao">
<constructor-arg ref="dataSource" />
</bean>
<beans profile="test">
<jdbc:embedded-database id="dataSource" type="H2" />
</beans>
<beans profile="prod">
<jee:jndi-lookup id="ds"
jndi-name="java:comp/env/jdbc/ds" />
</beans>
© Zenika 2011 Spring 3.1 17

18. Environment / Profile
• Let's reach the clouds!
<bean class="com.zenika.ContactDao">
<constructor-arg ref="dataSource" />
</bean>
<beans profile="dev">
<jdbc:embedded-database id="dataSource" type="H2" />
</beans>
<beans profile="cloud">
<cloud:data-source id="dataSource" service-name="contactDs"/>
</beans>
© Zenika 2011 Spring 3.1 18

19. Environment / Profile
• Creating the application context for the test profile
GenericXmlApplicationContext ctx =
new GenericXmlApplicationContext();
ctx.getEnvironment().setActiveProfiles("test");
ctx.load("classpath:/application-context.xml");
ctx.refresh();
© Zenika 2011 Spring 3.1 19

20. Environment / Profile
• Activating a profile declaratively
-Dspring.profiles.active="prod"
© Zenika 2011 Spring 3.1 20

21. Environment / Profile
• Bootstrapping with the TestContext framework
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:/application-context.xml")
@ActiveProfiles("test")
public class ProfileTest {
@Autowired private ContactDao contactDao;
@Test public void getContact() throws Exception {
...
}
}
© Zenika 2011 Spring 3.1 21

22. Environment / Profile
• Just « prod » profile
<bean class="com.zenika.spring31.ContactDao">
<constructor-arg ref="dataSource" />
</bean>
<beans profile="prod">
<jee:jndi-lookup id="ds"
jndi-name="java:comp/env/jdbc/ds" />
</beans>
© Zenika 2011 Spring 3.1 22

23. Environment / Profile
• Override what you need in the test
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(
loader=AnnotationConfigContextLoader.class
)
public class SpecialProfileTest {
@Autowired private ContactDao contactDao;
@Test public void getContact() throws Exception {
...
}
@Configuration
@ImportResource("classpath:/application-context.xml")
static class ContextConfiguration {
@Bean public DataSource dataSource() {
return new EmbeddedDatabaseBuilder().build();
}
}
}
© Zenika 2011 Spring 3.1 23

24. Java configuration
• Nothing equivalent to XML namespaces so far...
@Transactional
@Repository
public class HibernateContactRepo { ... }
<context:component-scan base-package="com.zenika" />
<tx:annotation-driven />
© Zenika 2011 Spring 3.1 24

25. Java configuration
• Annotations equivalent to common XML shortcuts
@Transactional
@Repository
public class HibernateContactRepo { ... }
@Configuration
@EnableTransactionManagement
@ComponentScan(basePackageClasses=HibernateContactRepo.class)
public class ContextConfiguration { ... }
© Zenika 2011 Spring 3.1 25

26. Java configuration
• Annotations equivalent to common XML shortcuts
@Configuration
@EnableTransactionManagement
@ComponentScan(basePackageClasses=HibernateContactRepo.class)
public class ContextConfiguration {
@Bean public SessionFactory sf() throws Exception {
return new AnnotationSessionFactoryBuilder()
.setDataSource(dataSource())
.setPackagesToScan(Contact.class.getPackage().getName())
.buildSessionFactory();
}
@Bean public PlatformTransactionManager tm() throws Exception {
return new HibernateTransactionManager(sf());
}
@Bean public DataSource dataSource() {
return new EmbeddedDatabaseBuilder()
.setType(EmbeddedDatabaseType.H2).build();
}
}
© Zenika 2011 Spring 3.1 26

27. Spring JPA
• More support for persistence in Spring JPA
public interface ContactRepository
extends JpaRepository<Contact, Long> { }
<jpa:repositories base-package="com.zenika.jpa" />
long initialCount = contactRepo.count();
Contact contact = new Contact();
contact.setFirstname("Arnaud");
contact.setLastname("Cogoluègnes");
contactRepo.save(contact);
Assert.assertEquals(initialCount+1, contactRepo.count());
© Zenika 2011 Spring 3.1 27

28. Spring JPA
• Define your own method, following conventions
public interface ContactRepository
extends JpaRepository<Contact, Long> {
List<Contact> findByFirstname(String firstname);
}
List<Contact> contacts = contactRepo.findByFirstname("Arnaud");
© Zenika 2011 Spring 3.1 28

29. Spring JPA
• Define JPQL queries for methods
public interface ContactRepository
extends JpaRepository<Contact, Long> {
@Query("from Contact c where lower(c.firstname) = lower(?1)")
List<Contact> find(String search);
}
List<Contact> contacts = contactRepo.find("arnaud");
© Zenika 2011 Spring 3.1 29

30. Spring JPA
• Built-in support for pagination
Pageable request = new PageRequest(1,2,new Sort("lastname"));
Page<Contact> page = contactRepo.findAll(request);
List<Contact> contacts = page.getContent();
long total = page.getTotalElements();
long number = page.getNumberOfElements();
© Zenika 2011 Spring 3.1 30

31. Quick note on Spring Data
• Spring JPA is part of the Spring Data project
• Spring Data is an umbrella project
• Spring Data provides Spring support for « new » data
access technologies
• MongoDB, Neo4j, Riak, Redis, Hadoop
• Support planned for additional NoSQL technologies
• HBase, Cassandra, CouchDB
• Don't hesitate to check out Spring Data!
• http://www.springsource.org/spring-data
© Zenika 2011 Spring 3.1 31

32. Cache support in Spring 3.1
• What about some transparent cache on method calls?
public interface ContactRepository
extends JpaRepository<Contact, Long> {
Contact findOne(Long id);
}
Contact contact = contactRepo.findOne(contact.getId());
contact = contactRepo.findOne(contact.getId());
Hibernate: select contact0_.id as id0_0_, ...
Hibernate: select contact0_.id as id0_0_, ...
© Zenika 2011 Spring 3.1 32

33. Cache support in Spring 3.1
• Let's combine Spring JPA and Spring 3.1's cache support !
• NB: the cache support works on any kinds of beans
public interface ContactRepository
extends JpaRepository<Contact, Long> {
@Cacheable("contacts")
Contact findOne(Long id);
}
Contact contact = contactRepo.findOne(contact.getId());
contact = contactRepo.findOne(contact.getId());
Hibernate: select contact0_.id as id0_0_, ...
© Zenika 2011 Spring 3.1 33

34. Cache support in Spring 3.1
• This is how to configure the cache
<cache:annotation-driven />
<bean id="cacheManager"
class="o.s.cache.support.SimpleCacheManager">
<property name="caches">
<set>
<bean class="o.s.cache.concurrent.ConcurrentMapCache"
c:name="contacts" />
</set>
</property>
</bean>
© Zenika 2011 Spring 3.1 34

35. Cache support in Spring 3.1
• The cache support is an abstraction
• The Spring Framework provides implementations
• SimpleCacheManager
• Uses collections of caches
• Useful for testing or small, non-distributed environments
• EhCacheCacheManager
• Backed up by Ehcache
• The Spring Gemfire project ships with an implementation
© Zenika 2011 Spring 3.1 35

36. Cache support in Spring 3.1
• Can use expression for keys
public interface ContactRepository
extends JpaRepository<Contact, Long> {
@Cacheable(value="contacts",key="#p0+'.'+#p1")
Contact findByLastnameAndFirstname(String lastname,
String firstname);
}
Contact contact = contactRepo.findByLastnameAndFirstname(
"Cogoluègnes", "Arnaud");
contact = contactRepo.findByLastnameAndFirstname(
"Cogoluègnes", "Arnaud");
Hibernate: select contact0_.id as id0_, ...
© Zenika 2011 Spring 3.1 36

37. Cache support in Spring 3.1
• Method can do some housekeeping with @CacheEvict
@Transactional
public interface ContactRepository
extends JpaRepository<Contact, Long> {
@Cacheable("contacts")
Contact findOne(Long id);
@CacheEvict(value="contacts",key="#p0.id")
Contact save(Contact contact);
}
© Zenika 2011 Spring 3.1 37

38. Cache support in Spring 3.1
• Spring's cache support can be used
• on the data access layer
• replaces 2nd level cache or provides cache for a JDBC-based
layer
• at the web tier level
• caches business services calls or web services calls
© Zenika 2011 Spring 3.1 38

39. Spring MVC enhancements
• Easier registration of HttpMessageConverters
• But what is a HttpMessageConverter anyway?
• HttpMessageConverters are used in Spring's REST
support
• Java object to HTTP response conversion
• From Java to XML, JSON, etc.
• HTTP request to Java object conversion
• From XML, JSON to Java
• On the server but on the client side as well...
© Zenika 2011 Spring 3.1 39

40. Spring MVC enhancements
• Easier registration with a dedicated XML tag
• Used to be directly at the HandlerAdapter level
<mvc:annotation-driven>
<mvc:message-converters register-defaults="false">
<bean class="com.zenika.web.ContactHttpMessageConverter" />
</mvc:message-converters>
</mvc:annotation-driven>
© Zenika 2011 Spring 3.1 40

41. Spring MVC enhancements
• Java-based configuration
• Same as <mvc:annotation-driven />
@Configuration
@EnableWebMvc
public class WebConfig extends WebMvcConfigurerAdapter {
@Override
public void configureMessageConverters(
List<HttpMessageConverter<?>> converters) {
converters.add(new ContactHttpMessageConverter());
}
}
© Zenika 2011 Spring 3.1 41

42. Spring MVC enhancements
• Big refactoring on the way to process annotations
@Controller
public class ContactController {
@Autowired private ContactRepository repo;
@RequestMapping(value="/contacts/{id}",
method=RequestMethod.GET
)
@ResponseBody
public Contact get(@PathVariable Long id) {
return repo.findOne(id);
}
}
© Zenika 2011 Spring 3.1 42

43. Spring MVC enhancements
• Who used to process annotations like @RequestMapping,
@RequestParam, etc?
• Answer: the AnnotationMethodHandlerAdapter.
• Processing was hard-coded in the class
• Spring 3.1 introduced the HandlerMethod abstraction
• RequestMappingHandlerMapping
• RequestMappingHandlerAdapter
© Zenika 2011 Spring 3.1 43

44. Spring MVC enhancements
• Consequences of the HandlerMethod abstraction
• Backward compatible (@RequestMapping, @RequestParam
& co).
• More fine-grained control over controller method execution
• Possible interception around the invocation of the controller
• Pluggable mechanism on method argument
• You can create your own @RequestParam-like annotations!
• Check the HandlerMethodArgumentResolver and
HandlerMethodReturnValueHandler interfaces
© Zenika 2011 Spring 3.1 44

45. Support for Servlet 3.0
• Servlet 3.0 allows for programmatic registration
• ServletContext.addServlet(String, Servlet)
• ServletContext.addFilter(String, Filter)
• Hook for frameworks
• ServletContainerInitializer
• Implementations listed in META-INF/services
• In Spring: SpringServletContainerInitializer
© Zenika 2011 Spring 3.1 45

46. Support for Servlet 3.0
• SpringServletContainerInitializer triggers
WebApplicationInitializers
• WebApplicationInitializer
• The API to use
• Detected and called by Spring (through the web container)
• Used for initialization
• Registering a DispatcherServlet
• Bootstrapping the Spring ApplicationContext
© Zenika 2011 Spring 3.1 46

47. Support for Servlet 3.0
• No need of web.xml anymore
public class ZenContactInitializer
implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext sc) throws ServletException {
AnnotationConfigWebApplicationContext rootContext =
new AnnotationConfigWebApplicationContext();
rootContext.register(WebConfig.class);
sc.addListener(new ContextLoaderListener(rootContext));
AnnotationConfigWebApplicationContext dispatcherContext =
new AnnotationConfigWebApplicationContext();
dispatcherContext.register(DispatcherConfig.class);
ServletRegistration.Dynamic dispatcher = sc.addServlet(
"dispatcher", new DispatcherServlet(dispatcherContext));
dispatcher.setLoadOnStartup(1);
dispatcher.addMapping("/main");
}
}
© Zenika 2011 Spring 3.1 47

48. Resources
• Summary
• http://blog.springsource.com/2011/02/11/spring-framework-3-1-m1-released/
• http://blog.springsource.com/2011/06/09/spring-framework-3-1-m2-released/
• Environment
• http://blog.springsource.com/2011/02/14/spring-3-1-m1-introducing-profile/
• http://blog.springsource.com/2011/06/21/spring-3-1-m2-testing-with-configuration-
classes-and-profiles/
• http://blog.springsource.com/2011/02/15/spring-3-1-m1-unified-property-management/
• Cache abstraction
• http://blog.springsource.com/2011/02/23/spring-3-1-m1-caching/
• Spring JPA
• http://blog.springsource.com/2011/02/10/getting-started-with-spring-data-jpa/
• http://blog.springsource.com/2011/07/27/fine-tuning-spring-data-repositories/
• Spring MVC
• http://blog.springsource.com/2011/02/21/spring-3-1-m1-mvc-namespace-
enhancements-and-configuration/
• http://blog.springsource.com/2011/06/13/spring-3-1-m2-spring-mvc-enhancements-2/
© Zenika 2011 Spring 3.1 48

49. Questions ?
© Zenika 2011 Spring 3.1 49