Significantly refactored the way that patch path expressions are handled and evaluated. The new design is centered around SpelPath that is aware of the original path as well as the derived SpEL expression. That SpelPath then requires clients to bind it to a type so that the original path can be validated (and rejected if invalid) and provide API to read, set, copy and move values backed by the original path. Both SpelPath and TypedSpelPath instances are cached to avoid repeated creation.
PatchOperation implementations now provide more fluent factory methods, in some cases via intermediate builders. Removed a lot of obsolete code that created JsonNodes from a list of PatchOperations as we don't actually use that functionality anywhere. Removed obsolete generics where possible.
We now inspect the user class of the given bean type in BasePathAwareHandlerMapping.isHandler(…). We can't use AnnotationUtils as @RepositoryRestController is also annotated with @BasePathAwareController but must not be handled by this mapping.
Previously, the SpEL expression created from JSON Patch path expressions were executed without double checking whether these paths actually exist on the target object in the first place. This check is now in place.
We now also catch SpelEvaluationException in the attempt to set a null value for an expression as Spring 5 now reports a failed attempt (e.g. if the target type is not nullable) using that type whereas Spring 4.3 threw a NullPointerException.
Fixed the setup of our custom ExceptionHandlerExceptionResolver to conclude with a call to afterPropertiesSet() to make sure it's properly initialized.
We now expose the constructor that takes a RelProvider in RepositoryResourceMappings so that clients can tweak the default relation names. Changed the order of constructor parameters of (previously) non-public constructors for consistency.
The RelProvider to be used with the mappings can now be configured via RepositoryRestConfiguration and defaults to the EvoInflector based one.
When a PATCH call using JSON Patch tried to append an item to an empty collection, it previously failed to look up the type to unmarshal the incoming payload to. We now inspect the declared types on the wrapped object's property to determine that type for append operations.
Also, an uninitialized collection is now initialized using Spring's CollectionFactory.
