This new hook in the AbstractEnvironment lifecycle allows for more
explicit and predictable customization of property sources by
subclasses. See Javadoc and existing implementations for detail.
Issue: SPR-8354
AbstractEnvironment and subclasses now register a reserved default
profile named literally 'default' such that with no action on the part
of the user, beans defined against the 'default' profile will be
registered - if no other profiles are explicitly activated.
For example, given the following three files a.xml, b.xml and c.xml:
a.xml
-----
<beans> <!-- no 'profile' attribute -->
<bean id="a" class="com.acme.A"/>
</beans>
b.xml
-----
<beans profile="default">
<bean id="b" class="com.acme.B"/>
</beans>
c.xml
-----
<beans profile="custom">
<bean id="c" class="com.acme.C"/>
</beans>
bootstrapping all of the files in a Spring ApplicationContext as
follows will result in beans 'a' and 'b', but not 'c' being registered:
ApplicationContext ctx = new GenericXmlApplicationContext();
ctx.load("a.xml");
ctx.load("b.xml");
ctx.load("c.xml");
ctx.refresh();
ctx.containsBean("a"); // true
ctx.containsBean("b"); // true
ctx.containsBean("c"); // false
whereas activating the 'custom' profile will result in beans 'a' and
'c', but not 'b' being registered:
ApplicationContext ctx = new GenericXmlApplicationContext();
ctx.load("a.xml");
ctx.load("b.xml");
ctx.load("c.xml");
ctx.getEnvironment().setActiveProfiles("custom");
ctx.refresh();
ctx.containsBean("a"); // true
ctx.containsBean("b"); // false
ctx.containsBean("c"); // true
that is, once the 'custom' profile is activated, beans defined against
the the reserved default profile are no longer registered. Beans not
defined against any profile ('a') are always registered regardless of
which profiles are active, and of course beans registered
against specific active profiles ('c') are registered.
The reserved default profile is, in practice, just another 'default
profile', as might be added through calling env.setDefaultProfiles() or
via the 'spring.profiles.default' property. The only difference is that
the reserved default is added automatically by AbstractEnvironment
implementations. As such, any call to setDefaultProfiles() or value set
for the 'spring.profiles.default' will override the reserved default
profile. If a user wishes to add their own default profile while
keeping the reserved default profile as well, it will need to be
explicitly redeclared, e.g.:
env.addDefaultProfiles("my-default-profile", "default")
The reserved default profile(s) are determined by the value returned
from AbstractEnvironment#getReservedDefaultProfiles(). This protected
method may be overridden by subclasses in order to customize the
set of reserved default profiles.
Issue: SPR-8203
Allows convenient creation of a Properties-based PropertySource from a
Spring Resource object or resource location string such as
"classpath:com/myco/app.properties" or "file:/path/to/file.properties"
Issue: SPR-8328
Users may now call #setRequiredProperties(String...) against the
Environment (via its ConfigurablePropertyResolver interface) in order
to indicate which properties must be present.
Environment#validateRequiredProperties() is invoked by
AbstractApplicationContext during the refresh() lifecycle to perform
the actual check and a MissingRequiredPropertiesException is thrown
if the precondition is not satisfied.
Issue: SPR-8323
This change is in support of certain polymorphism cases in
@Configuration class inheritance hierarchies. Consider the following
scenario:
@Configuration
public abstract class AbstractConfig {
public abstract Object bean();
}
@Configuration
public class ConcreteConfig {
@Override@Bean
public BeanPostProcessor bean() { ... }
}
ConcreteConfig overrides AbstractConfig's #bean() method with a
covariant return type, in this case returning an object of type
BeanPostProcessor. It is critically important that the container
is able to detect the return type of ConcreteConfig#bean() in order
to instantiate the BPP at the right point in the lifecycle.
Prior to this change, the container could not do this.
AbstractAutowireCapableBeanFactory#getTypeForFactoryMethod called
ReflectionUtils#getAllDeclaredMethods, which returned Method objects
for both the Object and BeanPostProcessor signatures of the #bean()
method. This confused the implementation sufficiently as not to
choose a type for the factory method at all. This means that the
BPP never gets detected as a BPP.
The new method being introduced here, #getUniqueDeclaredMethods, takes
covariant return types into account, and filters out duplicates,
favoring the most specific / narrow return type.
Additionally, it filters out any CGLIB 'rewritten' methods, which
is important in the case of @Configuration classes, which are
enhanced by CGLIB. See the implementation for further details.
Includes the introduction of AnnotationUtils#findAllAnnotationAttributes
to support iterating through all annotations declared on a given type
and interrogating each for the presence of a meta-annotation. See tests
for details.
Introduce FeatureSpecification interface and implementations
FeatureSpecification objects decouple the configuration of
spring container features from the concern of parsing XML
namespaces, allowing for reuse in code-based configuration
(see @Feature* annotations below).
* ComponentScanSpec
* TxAnnotationDriven
* MvcAnnotationDriven
* MvcDefaultServletHandler
* MvcResources
* MvcViewControllers
Refactor associated BeanDefinitionParsers to delegate to new impls above
The following BeanDefinitionParser implementations now deal only
with the concern of XML parsing. Validation is handled by their
corresponding FeatureSpecification object. Bean definition creation
and registration is handled by their corresponding
FeatureSpecificationExecutor type.
* ComponentScanBeanDefinitionParser
* AnnotationDrivenBeanDefinitionParser (tx)
* AnnotationDrivenBeanDefinitionParser (mvc)
* DefaultServletHandlerBeanDefinitionParser
* ResourcesBeanDefinitionParser
* ViewControllerBeanDefinitionParser
Update AopNamespaceUtils to decouple from XML (DOM API)
Methods necessary for executing TxAnnotationDriven specification
(and eventually, the AspectJAutoProxy specification) have been
added that accept boolean arguments for whether to proxy
target classes and whether to expose the proxy via threadlocal.
Methods that accepted and introspected DOM Element objects still
exist but have been deprecated.
Introduce @FeatureConfiguration classes and @Feature methods
Allow for creation and configuration of FeatureSpecification objects
at the user level. A companion for @Configuration classes allowing
for completely code-driven configuration of the Spring container.
See changes in ConfigurationClassPostProcessor for implementation
details.
See Feature*Tests for usage examples.
FeatureTestSuite in .integration-tests is a JUnit test suite designed
to aggregate all BDP and Feature* related tests for a convenient way
to confirm that Feature-related changes don't break anything.
Uncomment this test and execute from Eclipse / IDEA. Due to classpath
issues, this cannot be compiled by Ant/Ivy at the command line.
Introduce @FeatureAnnotation meta-annotation and @ComponentScan impl
@FeatureAnnotation provides an alternate mechanism for creating
and executing FeatureSpecification objects. See @ComponentScan
and its corresponding ComponentScanAnnotationParser implementation
for details. See ComponentScanAnnotationIntegrationTests for usage
examples
Introduce Default[Formatting]ConversionService implementations
Allows for convenient instantiation of ConversionService objects
containing defaults appropriate for most environments. Replaces
similar support originally in ConversionServiceFactory (which is now
deprecated). This change was justified by the need to avoid use
of FactoryBeans in @Configuration classes (such as
FormattingConversionServiceFactoryBean). It is strongly preferred
that users simply instantiate and configure the objects that underlie
our FactoryBeans. In the case of the ConversionService types, the
easiest way to do this is to create Default* subtypes. This also
follows convention with the rest of the framework.
Minor updates to util classes
All in service of changes above. See diffs for self-explanatory
details.
* BeanUtils
* ObjectUtils
* ReflectionUtils
Designed primarily for use in conjunction with web applications
to provide a convenient mechanism for configuring the container
programmatically.
ApplicationContextInitializer implementations are specified through the
new "contextInitializerClasses" servlet context parameter, then detected
and invoked by ContextLoader in its customizeContext() method.
In any case, the semantics of ApplicationContextInitializer's
initialize(ConfigurableApplicationContext) method require that
invocation occur *prior* to refreshing the application context.
ACI implementations may also implement Ordered/PriorityOrdered and
ContextLoader will sort instances appropriately prior to invocation.
Specifically, this new support provides a straightforward way to
programmatically access the container's Environment for the purpose
of adding, removing or otherwise manipulating PropertySource objects.
See Javadoc for further details.
Also note that ApplicationContextInitializer semantics overlap to
some degree with Servlet 3.0's notion of ServletContainerInitializer
classes. As Spring 3.1 development progresses, we'll likely see
these two come together and further influence one another.
Chris Beams
Oliver Gierke
Sam Brannen
Rossen Stoyanchev
Arjen Poutsma
Juergen Hoeller
Keith Donald