Closes gh-22504

Closes gh-22409

Closes gh-22359

Closes gh-22331

Closes gh-22318

This allows for proper nested type conversion in @Value Optional fields analogous to method parameters, through a new TypeDescriptor-based method in the TypeConverter SPI. As an additional and less involved measure that is worth backporting, DefaultListableBeanFactory defensively checks for pre-converted Optional wrappers.

Issue: SPR-17607

The xml parser does not fill in defaults provided in the XSD when
validation is disabled. As a result, attributes like default-lazy-init
will not receive the value "default" but an empty string.

With this commit, BeanDefinitionParserDelegate now takes this into
account, checking default values against empty string as well as
"default".

As a consequence, default-lazy-init attribute should now work correctly
even when the XSD validation is disabled.

Issue: SPR-8335

Closes gh-1452

See gh-1452

ResolvableType-based matching consistently respects generic factory method return type (even for pre-initialized raw singleton instance)

Issue: SPR-17524

Issue: SPR-15540

Issue: SPR-17508

See gh-2019

Issue: SPR-17086

Issue: SPR-17452

Issue: SPR-17392

Issue: SPR-17358
Issue: SPR-8891

Issue: SPR-17358

Includes consistent upfront resolution of factory method annotations.

Issue: SPR-8891

Issue: SPR-17356

Prefix the opening brace with a single space in some classes.
Replace tab character with space in javadoc of AttributeAccessor.
Also fix some other trivial formatting errors.

Closes gh-1979

Issue: SPR-17299

Issue: SPR-17272

Support for Kotlin primary constructor and non-default public constructors in addition to default instantiation, aligned with AnnotationConfigApplicationContext and model attribute processing.

Issue: SPR-17292

Declaring beanPostProcessors (and also embeddedValueResolvers) as CopyOnWriteArrayList prevents ConcurrentModificationExceptions in case of concurrent registration/access attempts.

Issue: SPR-17286

Issue: SPR-17282

Issue: SPR-17272

Also includes setters for role and description.

Issue: SPR-17275

Includes fallback match for collection/map dependency if qualified.

Issue: SPR-17272
Issue: SPR-17197