Remove canBypassConvert() methods from the ConversionService SPI
interface, restoring it to the previous Spring 3.1 incarnation.
Bypassing conversion is now only supported when using a
GenericConversionService.
Issue: SPR-9566
Bypass ObjectToObject conversion when source and object types are
identical and protect against a null source object.
Prior to this commit the TypeDescriptor was used to determine if
conversion was necessary. This caused issues when comparing a
descriptor with annotations to one without. The updated code
now compares using TypeDescriptor.getType().
The ObjectToObject converter will now no longer attempt to convert
null source objects.
Issue: SPR-9933
TypeDescriptor.valueOf now uses GenericCollectionTypeResolver to resolve
Collection and Map element types whereas previously this information was
simply not supported, i.e. null.
Issue: SPR-9257
Prior to this commit conversion between like types would often result in
a copy of the object. This can be problematic in the case of large byte
arrays and objects that do not have a default constructor.
The ConversionService SPI now includes canBypassConvert methods that can
be used to deduce when conversion is not needed. Several existing
converters have been updated to ensure they only apply when source and
target types differ.
This change introduces new methods to the ConversionService that will
break existing implementations. However, it anticipated that most users
are consuming the ConversionService interface rather then extending it.
Issue: SPR-9566
Introduce new ConditionalConversion interface that can be applied to
Converter, ConverterFactory or GenericConverter interfaces to make
them conditional. Prior to this commit the only
ConditionalGenericConverter could be conditional.
Issue: SPR-9928
Refactor internal workings of GenericConversionService in order to
better support future enhancements. This commit should not affect
existing behavior.
Issue: SPR-9927
Prior to this commit, the PropertyResolver API (and therefore the
Environment API) allowed callers a choice between
#resolvePlaceholders and #resolveRequiredPlaceholders for low-level
${placeholder} resolution. However, when calling the higher level
#getProperty variants, users had no control over whether property
values returned with unresolvable ${placeholders} would result in an
exception or simply be passed through.
This commit introduces a #setIgnoreUnresolvableNestedPlaceholders
property via ConfigurablePropertyResolver, defaulting to false, the
value of which is respected by AbstractPropertyResolver#getProperty
method implementations. See the new test in
PropertySourcesPropertyResolverTests for usage examples.
Issue: SPR-9569, SPR-9473
This should be significantly faster than our standard algorithm, for a very common case. Motivated by SPR-9802, even if the fix there uses a different approach, with transaction name determination not calling getMostSpecificMethod at all anymore.
Issue: SPR-9802
Prior to this commit, JibxMarshaller used a SAX ContentHandler to
marshal to StAX XMLEventWriters, which inadvertently resulted in the
deletion of XML comments.
After this commit, JibxMarshaller adapts the XMLEventWriter into an
XMLStreamWriter and comments are preserved.
Issue: SPR-9768
Prior to this change, @ComponentScan required the declaration of
exactly one of the #value, #basePackage or #basePackageClasses
attributes in order to determine which package(s) to scan.
This commit introduces support for base package inference, relaxing the
above requirement and falling back to scanning the package in which the
@ComponentScan-annotated class is declared.
Issue: SPR-9586
Update the ReflectiveAspectJAdvisorFactory class to sort candidate
AOP methods based on their annotation first and method name second.
Prior to this the order of aspects created from annotated methods
could differ depending on the underling JVM, as first noticed under
JDK7 in SPR-9729.
- ConvertingComparator and InstanceComparator have been introduced in
support of this change, per SPR-9730.
- A shared static INSTANCE field has been added to ComparableComparator
to avoid unnecessary instantiation costs within ConvertingComparator
as well as to prevent generics warnings during certain caller
scenarios.
Issue: SPR-9729, SPR-9730
This change fixes a minor bug with the implementation of
ConfigurableEnvironment#merge, introduced in SPR-9444. During a merge
of two environments A and B, where A has default profiles [prod] and B
has default profiles [default] (the so-called 'reserved default
profile'), B would complete the merge process having a collection of
profiles reading [default, prod], which is incorrect.
This commit explicitly ensure's that B's reserved default profile is
removed if A has a set of default profiles greater than zero. If A
consists only of [default], B will inherit it during the merge
correctly; if A consists of [p1, p2], B will result in [p1, p2] as
well; if B consists of [p1] and A of [p2, p3], B will result in
[p1, p2, p3] post-merge.
Issue: SPR-9761, SPR-9444
Before this commit, the CachedIntrospectionResults was hard-coded to
create ExtendedBeanInfos for bean classes. The ExtendedBeanInfo support
the JavaBeans property contract only.
This commit introduces the BeanInfoFactory, a strategy for creating
BeanInfos. Through this strategy, it is possible to support
beans that do not necessarily implement the JavaBeans contract (i.e.
have a different getter or setter style).
BeanInfoFactories are are instantiated by the
CachedIntrospectionResults, which looks for
'META-INF/spring.beanInfoFactories' files on the class path. These files
contain one or more BeanInfoFactory class names. When a BeanInfo is to
be created, the CachedIntrospectionResults will iterate through the
factories, asking it to create a BeanInfo for the given bean class. If
none of the factories support it, an ExtendedBeanInfo is created as a
default.
This commit also contains a change to Property, allowing BeanWrapperImpl
to specify the property name at construction time (as opposed to using
Property#resolveName(), which supports the JavaBeans contract only).
Issue: SPR-9677
This change makes it possible to use the RestTemplate to read an HTTP
response into a target generic type object. The RestTemplate has three
new exchange(...) methods that accept ParameterizedTypeReference -- a
new class that enables capturing and passing generic type info.
See the Javadoc of the three new methods in RestOperations for a
short example.
To support this feature, the HttpMessageConverter is now extended by
GenericHttpMessageConverter, which adds a method for reading an
HttpInputMessage to a specific generic type. The new interface
is implemented by the MappingJacksonHttpMessageConverter and also by a
new Jaxb2CollectionHttpMessageConverter that can read read a generic
Collection where the generic type is a JAXB type annotated with
@XmlRootElement or @XmlType.
Issue: SPR-7023
CGLIB 3 has been released in order to depend on ASM 4, which Spring now
depends on internally (see previous commit).
This commit eliminates spring-beans' optional dependency on cglib-nodep
v2.2 and instead repackages net.sf.cglib => org.springframework.cglib
much in the same way we have historically done with ASM.
This change is beneficial to users in several ways:
- Eliminates the need to manually add CGLIB to the application
classpath; especially important for the growing number of
@Configuration class users. Java-based configuration functionality,
along with proxy-target-class and method injection features now
work 'out of the box' in Spring 3.2.
- Eliminates the possibility of conflicts with other libraries that
may dependend on differing versions of CGLIB, e.g. Hibernate
3.3.1.ga and its dependency on CGLIB 2.1.3 would easily cause a
conflict if the application were depending on CGLIB 3 for
Spring-related purposes.
- Picks up CGLIB 3's changes to support ASM 4, meaning that CGLIB is
that much less likely to work well in a Java 7 environment due to
ASM 4's support for transforming classes with invokedynamic
bytecode instructions.
On CGLIB and ASM:
CGLIB's own dependency on ASM is also transformed along the way to
depend on Spring's repackaged org.springframework.asm, primarily to
eliminate unnecessary duplication of ASM classfiles in spring-core and
in the process save around 100K in the final spring-core JAR file size.
It is coincidental that spring-core and CGLIB currently depend on the
exact same version of ASM (4.0), but it is also unlikely to change any
time soon. If this change does occur and versions of ASM drift, then
the size optimization mentioned above will have to be abandoned. This
would have no compatibility impact, however, so this is a reasonable
solution now and for the forseeable future.
On a mysterious NoClassDefFoundError:
During the upgrade to CGLIB 3.0, Spring test cases began failing due to
NoClassDefFoundErrors being thrown from CGLIB's DebuggingClassWriter
regarding its use of asm-util's TraceClassVisitor type. previous
versions of cglib-nodep, particularly 2.2, did not cause this behavior,
even though cglib-nodep has never actually repackaged and bundled
asm-util classes. The reason for these NoClassDefFoundErrors occurring
now is still not fully understood, but appears to be due to subtle JVM
bytecode preverification rules. The hypothesis is that due to minor
changes in DebuggingClassWriter such as additional casts, access to
instance variables declared in the superclass, and indeed a change in
the superclass hierarchy, preverification may be kicking in on the
toByteArray method body, at which point the reference to the missing
TraceClassVisitor type is noticed and the NCDFE is thrown. For this
reason, a dummy implementation of TraceClassVisitor has been added to
spring-core in the org.springframework.asm.util package. This class
simply ensures that Spring's own tests never result in the NCDFE
described above, and more importantly that Spring's users never
encounter the same.
Other changes include:
- rename package-private Cglib2AopProxy => CglibAopProxy
- eliminate all 'cglibAvailable' checks, warnings and errors
- eliminate all 'CGLIB2' language in favor of 'CGLIB'
- eliminate all mention in reference and java docs of needing to add
cglib(-nodep) to one's application classpath
Issue: SPR-9669
ASM 4.0 is generally compatibile with Java 7 classfiles, particularly
including 'invokedynamic' instructions. This is important when
considering that Spring's component-scanning support is internally
ASM-based and it is increasingly likely that component classes having
invokedynamic instructions may be encountered and read by ASM.
This upgrade, then, is primarily preventive in nature.
Changes include:
- upgrade from ASM 2.2.3 to ASM 4.0
- adapt to ASM API changes as necessary throughout spring-core,
resulting in no impact to the public Spring API.
- remove dedicated spring-asm module
- use new :spring-core:asmRepackJar task to repackage
org.objectweb.asm => org.springframework.asm as per usual and write
repackaged classes directly into spring-core jar
The choice to eliminate the spring-asm module altogether and instead
inline the repackaged classes directly into spring-core is first to
eliminate an otherwise unnecessary second jar. spring-core has a
non-optional dependency on spring-asm meaning it is always on the
application classpath. This change simplifies that situation by
consoliding two jars into one. The second reason for this choice is in
anticipation of upgrading CGLIB to version 3 and inlining it into
spring-core as well. See subsequent commit for details.
Issue: SPR-9669
- renamed resolveParameterizedReturnType() to
resolveReturnTypeForGenericMethod()
- fleshed out Javadoc for resolveReturnType() and
resolveReturnTypeForGenericMethod() regarding declaration of formal
type variables
- improved wording in log statements and naming of local variables
within resolveReturnTypeForGenericMethod()
Issue: SPR-9493
Prior to this change, PropertySourcesPropertyResolver (and therefore
all AbstractEnvironment) implementations failed to resolve nested
placeholders as in the following example:
p1=v1
p2=v2
p3=${v1}:{$v2}
Calls to PropertySource#getProperty for keys 'p1' and 'v1' would
successfully return their respective values, but for 'p3' the return
value would be the unresolved placeholders. This behavior is
inconsistent with that of PropertyPlaceholderConfigurer.
PropertySourcesPropertyResolver #getProperty variants now resolve any
nested placeholders recursively, throwing IllegalArgumentException for
any unresolvable placeholders (as is the default behavior for
PropertyPlaceholderConfigurer). See SPR-9569 for an enhancement that
will intoduce an 'ignoreUnresolvablePlaceholders' switch to make this
behavior configurable.
This commit also improves error output in
PropertyPlaceholderHelper#parseStringValue by including the original
string in which an unresolvable placeholder was found.
Issue: SPR-9473, SPR-9569
PropertySourcesPropertyResolver#containsProperty now
calls #containsProperty on each underlying PropertySource instead of
calling #getProperty and checking for null.
Issue: SPR-9529
Currently, if a factory method is parameterized and the corresponding
variable types are declared on the method itself instead of on the
enclosing class or interface, Spring always predicts the return type to
be Object, even if the return type can be explicitly inferred from the
method signature and supplied arguments (which are available in the bean
definition).
This commit introduces a new resolveParameterizedReturnType() method in
GenericTypeResolver that attempts to infer the concrete type for the
generic return type of a given parameterized method, falling back to the
standard return type if necessary. Furthermore,
AbstractAutowireCapableBeanFactory now delegates to
resolveParameterizedReturnType() when predicting the return type for
factory methods.
resolveParameterizedReturnType() is capable of inferring the concrete
type for return type T for method signatures similar to the following.
Such methods may potentially be static. Also, the formal argument list
for such methods is not limited to a single argument.
- public <T> T foo(Class<T> clazz)
- public <T> T foo(Object obj, Class<T> clazz)
- public <V, T> T foo(V obj, Class<T> clazz)
- public <T> T foo(T obj)
Issue: SPR-9493
Previously (since Spring 3.1.1) RecursiveAnnotationAttributesVisitor
logs at level WARN when ASM parsing encounters an annotation or an (enum
used within an annotation) that cannot be classloaded. This is not
necessarily indicative of an error, e.g. JSR-305 annotations such as
@Nonnull may be used only for static analysis purposes, but because
these annotations have runtime retention, they remain present in the
bytecode. Per section 9.6.1.2 of the JLS, "An annotation that is present
in the binary may or may not be available at run-time via the reflective
libraries of the Java platform."
This commit lowers the log level of these messages from warn to debug,
but leaves at warn level other messages dealing with the ability
reflectively read enum values from within annotations.
Issue: SPR-9233
The following syntax is now supported
<beans profile="p1,!p2">
@Profile("p1", "!p2")
indicating that the <beans> element or annotated component should
be processed only if profile 'p1' is active or profile 'p2' is not
active.
Issue: SPR-8728
