RESTful Java Web Services - Third Edition

Implementing client-side request message filters

JAX-RS lets you build a client-side request filter for REST API calls by implementing the javax.ws.rs.client.ClientRequestFilter interface. This filter is used for intercepting the REST API calls on the client itself.

A very common use case scenario where you may find these filters useful is for checking the accuracy of specific request parameters on the client itself. Even you can abort the call and return the error response object from these filters if the request parameter values are not properly specified.

The following code snippet illustrates how you can use ClientRequestFilter to ensure that all the requests carry the Client-Application header field, which you may use on the server for ...