Can Resteasy look into parameter's type for JAX-RS methods?

Question

We were using Resteasy 3.0.9 for our JAX-RS webservices, and recently switched to 3.0.19, where we started to see a lot of RESTEASY002142: Multiple resource methods match request warnings.

For example, we have methods like:

@Path("/{id}") 
public String getSome(UUID id)

@Path("/{id}") 
public String getSome(int id)

I'm not sure how it worked in 3.0.9, probably, we just were very lucky as Resteasy seems to select first method from all candidates (and 3.0.19 sorts candidate methods).

One solution is to explicitly specify regex: @Path("/{id : [0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}}")

But is there a way to somehow tell Resteasy to look into method parameters and construct appropriate regex automatically?

Answer 1

As far as I know, RESTEasy won't take the method parameter type into consideration when matching a request. According the JSR-339 (that RESTEasy implements), this is how the request matching process works:

A request is matched to the corresponding resource method or sub-resource method by comparing the normalized request URI, the media type of any request entity, and the requested response entity format to the metadata annotations on the resource classes and their methods. If no matching resource method or sub-resource method can be found then an appropriate error response is returned. [...]

The JAX-RS implementations must match the requested URI with the @Path annotation values. In the @Path annotation value you can define variables, that are denoted by braces ({ and }).

As part of the request matching, the JAX-RS implementation will replace each URI template variable with the specified regular expression or ([ˆ/]+?) if no regular expression is specified.

To address the situation you mentioned in your question, you should specify a regex to match UUIDs on one resource method:

@Path("{id : [0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}}")

And you also may consider a regex to match integers on the other resource method:

@Path("{id : \\d+}")