Issue: SPR-12549

Issue: SPR-12785

Prior to this commit, the implementation of equals() in EncodedResource
was based solely on the resource and encoding. Thus, if a Charset were
specified instead of an encoding, invocations of equals() would not
work as expected.

This commit addresses this issue by including the charset in the
implementation of equals() and introducing corresponding tests in a new
EncodedResourceTests class. Furthermore, this commit makes
EncodedResource immutable and updates all Javadoc to reflect support
for the encoding and charset properties.

Issue: SPR-12767

Issue: SPR-12766

This commit ensures Resources have consistent, non-empty, meaningful
implementations for getDescription(), thus ensuring that calls to
toString() (e.g., in log statements) no longer return an empty String.

This commit also polishes the Javadoc for various Resource
implementations.

Add StreamConverter to provide full support for converting
java.util.stream.Stream instances to and from collections or arrays.

Also attempt to convert the element type if necessary.

StreamConverter is registered by default in the DefaultConversionService
as long as Java8 is available.

Issue: SPR-12175

Issue: SPR-12701

Previously, the `@order` annotation was managed in an inconsistent way
when placed at the implementation level. For simple beans, it was
discovered properly but wasn't for beans requiring a proxy.

OrderComparator.SourceProvider now explicitly allows to return several
order sources; the default implementation returns not only the factory
method (if  any) but also the target class if it happens to be different
from the class of the bean.

Issue: SPR-12636

Prior to this change, the ShallowEtagHeaderFilter would use a
ResizableByteArrayOutputStream to internally write data and calculate
the ETag. While that implementation is faster than the regular
ByteArrayOutputStream (since it has a better strategy for growing the
internal buffer), a lot of buffer copying/writing still happens.

This change adds a new FastByteArrayOutputStream implementation that
internally uses a LinkedList<Byte[]> to store the content. So when
writing bytes to that OutputStream implementation, new byte[] are
added to the list when the previous ones are full. This saves most
of the instantiating/copying operations.

Note that new methods were added in DigestUtils to allow usage of
Streams instead of byte[], which is more efficient in our case.

Fixes #653

Issue: SPR-12081

This commit introduces test methods in CollectionFactoryTests that
demonstrate how the APIs for createCollection() and createMap() are not
type-safe, specifically regarding the use of generics, raw types, and
casting.

SPR-12483 introduced automatic type conversion support for EnumSet and
EnumMap. However, the corresponding changes in CollectionFactory
contradict the existing contract for the "create approximate" methods
by creating a copy of the supplied set or map, thereby potentially
including elements in the returned collection when the returned
collection should in fact be empty.

This commit addresses this issue by ensuring that the collections
returned by createApproximateCollection() and createApproximateMap()
are always empty.

Furthermore, this commit improves the Javadoc throughout the
CollectionFactory class.

Issue: SPR-12533

This commit introduces test methods in CollectionFactoryTests that
demonstrate how the APIs for createApproximateCollection() and
createApproximateMap() are not type-safe, specifically regarding the use
of generics, raw types, and casting.

This commit improves error handling in CollectionFactory by asserting
preconditions.

In addition, this commit introduces ConnectionFactoryTests.

JUnit 4.12 created a 'public' version of the previously 'internal'
AssumptionViolatedException.

This commit upgrades Spring's Assume class to use this new public
version.

Issue: SPR-12483

Issue: SPR-12473
(cherry picked from commit 5ac86803)

MutablePropertySources uses an internal CopyOnWriteArrayList for defensiveness against concurrent modifications

Issue: SPR-12428

Prior to this commit, JOptCommandLinePropertySource prevented the
possibility of non-String option arguments. This effectively prevents
the use of JOpt's #ofType support (which allows specifying custom
argument types).

Now, non-String arguments are detected and converted to strings as
necessary. JOpt's #ofType now works as expected. A test has been added
to cover this case.

AnnotationUtils favors local composed annotations over interface annotations and consistently logs introspection failures via lazily initialized logger

Issue: SPR-12355
Issue: SPR-12325
Issue: SPR-12329

Prior to this commit, `AntPathMatcher.extractPathWithinPattern` would
not process correctly `**` patterns and would only match *one* path
segment in the given path.

This commit changes `extractPathWithinPattern` to allow multiple path
segments to be matched against a single `**` pattern segment.

Issue: SPR-10515

Issue: SPR-12224

Update SystemEnvironmentPropertySource to attempt optimized Map lookups
first, and only fall-back to the defensive SecurityManager safe-mode
if these fail.

Issue: SPR-12224

Issue: SPR-12181

Issue: SPR-11310
Issue: SPR-10548

Revised ResourcePropertySource in order to avoid ConfigurationClassProcessor's AnnotationPropertySource subclass

Issue: SPR-12115

Fix CompositePropertySourceTests which fails when run we debug logging.

Rework the @PropertySource parsing logic recently changed in commit
7c608886 to deal with the same source appearing on a @Configuration
class and an @Import class.

Processing now occurs in a single sweep, with any previously added
sources being converted to a CompositePropertySource.

Issue: SPR-12115

Issue: SPR-12095

Issue: SPR-12078

Prior to this commit, given an enum which implements some interface,
GenericConversionService would select the String -> Enum converter even
if a converter for String -> SomeInterface was registered.  This also
affected converters that were registered for String ->
SomeBaseInterface, when SomeInterface extended SomeBaseInterface.

This change modifies the behavior of the private method
getClassHierarchy() by placing Enum.class as late as possible, pretty
much the same way as Object.class is handled.

Issue: SPR-12050