Document default property converters [SPR-15269]

Arend v. Reinersdorff opened SPR-15269 and commented

Spring includes by default a number of useful property converters. Ie values for the targetType parameter in PropertyResolver.getProperty(String key, Class targetType).

Unfortunately these default converters are not documented. The best answer on Stackoverflow suggests executing ConversionService.toString() to get a list of converters.

I was looking for documentation because I was surprised that java.io.File works as targetType while java.nio.file.Path does not. (Turns out File probably works because of the ObjectToObjectConverter that finds the File(String) constructor via reflection)

Affects: 4.3.6

Reference URL: http://docs.spring.io/spring/docs/4.3.6.RELEASE/spring-framework-reference/html/validation.html

Start with the validation reference documentation linked in the issue and the PropertyResolver.getProperty(String key, Class targetType) entry point. Inspect the default ConversionService converters, including the behavior noted for java.io.File and java.nio.file.Path; done means the supported default property target types and relevant limitations are documented.