Spring Boot REST @RequestParam not being Validated
<p>I have tried a number of examples from the net and cannot get Spring to validate my query string parameter. It doesn't seem execute the REGEX / fail.</p>

<pre><code>package my.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import javax.validation.Valid;
import javax.validation.constraints.Pattern;

import static org.springframework.web.bind.annotation.RequestMethod.GET;

@RestController
public class MyController {

    private static final String VALIDATION_REGEX = "^[0-9]+(,[0-9]+)*$";

    @RequestMapping(value = "/my/{id}", method = GET)
    public myResonseObject getMyParams(@PathVariable("id") String id,
                                       @Valid @Pattern(regexp = VALIDATION_REGEX) 
                                       @RequestParam(value = "myparam", required = true) String myParam) {
         // Do Stuff!
    }

}
</code></pre>

<p><strong>Current behaviour</strong></p>

<pre><code>PASS - /my/1?myparam=1
PASS - /my/1?myparam=1,2,3
PASS - /my/1?myparam=
PASS - /my/1?myparam=1,bob
</code></pre>

<p><strong>Desired behaviour</strong></p>

<pre><code>PASS - /my/1?myparam=1
PASS - /my/1?myparam=1,2,3
FAIL - /my/1?myparam=
FAIL - /my/1?myparam=1,bob
</code></pre>

<p>Thanks</p>