Interceptor que verifica se os parâmetros informados estão de acordo com a anotação @whitelist

ParametersValidatorInterceptor.java

import static br.com.caelum.vraptor.util.collections.Filters.hasAnnotation;
import static com.google.common.collect.Iterables.any;
import static java.util.Arrays.asList;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;

import br.com.caelum.vraptor.InterceptionException;
import br.com.caelum.vraptor.Intercepts;
import br.com.caelum.vraptor.core.InterceptorStack;
import br.com.caelum.vraptor.core.MethodInfo;
import br.com.caelum.vraptor.interceptor.Interceptor;
import br.com.caelum.vraptor.interceptor.ParametersInstantiatorInterceptor;
import br.com.caelum.vraptor.ioc.RequestScoped;
import br.com.caelum.vraptor.resource.ResourceMethod;

@Intercepts(after = ParametersInstantiatorInterceptor.class)
@RequestScoped
public class ParametersValidatorInterceptor implements Interceptor {

	private final MethodInfo methodInfo;

	public ParametersValidatorInterceptor(final MethodInfo methodInfo) {
		this.methodInfo = methodInfo;
	}

	public void intercept(final InterceptorStack stack, final ResourceMethod method,
			final Object resourceInstance) throws InterceptionException {
		Object[] parameters = methodInfo.getParameters();

		List<Object> filteredParameters = filterWithWhiteList(method, parameters);
		methodInfo.setParameters(filteredParameters.toArray());

		stack.next(method, resourceInstance);
	}

	private List<Object> filterWithWhiteList(final ResourceMethod method, final Object[] parameters) {
		List<Object> filtered = new ArrayList<Object>();
		Annotation[][] annotations = method.getMethod().getParameterAnnotations();

		for (int i = 0; i < annotations.length; i++) {
			Object parameter = parameters[i];

			for (Annotation annotation : annotations[i]) {
				if (annotation instanceof WhiteList) {
					WhiteList whiteList = (WhiteList) annotation;
					filtered.add(Clonefy.clone(parameter, whiteList.value()));
				}
			}
		}

		return filtered;
	}

	public boolean accepts(final ResourceMethod method) {
		return any(asList(method.getMethod().getParameterAnnotations()),
				hasAnnotation(WhiteList.class));
	}
}

o accepts poderia ficar assim:
return any(asList(method.getMethod().getParameterAnnotations()), hasAnnotation(WhiteList.class))

É uma sugestão de refactoring ou os métodos any e hasAnnotation existem? De quais classes eles são?

Ficou da hora :), parabéns cara.