It seems to be impossible to use CDI within a JAX-RS 2.0 ContainerRequestFilter, but it is possible to first use a WebFilter to obtain the service and then pass it along via attributes.

InjectionServlet.java

package com.swsandbox.resource;

import com.swsandbox.service.UserService;

import javax.inject.Inject;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import java.io.IOException;

@WebFilter(urlPatterns = "/*")
public class InjectionServlet implements Filter
{
    @Inject
    UserService userService;

    @Override
    public void init(FilterConfig filterConfig) throws ServletException
    {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
    {
        request.setAttribute("userService", userService);
        chain.doFilter(request, response);
    }

    @Override
    public void destroy()
    {

    }
}

MyFilter.java

package com.swsandbox.resource;

import com.swsandbox.service.UserService;

import javax.annotation.Priority;
import javax.ws.rs.Priorities;
import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerRequestFilter;
import javax.ws.rs.ext.Provider;
import java.io.IOException;

@Priority(Priorities.AUTHENTICATION)
@Provider
public class MyFilter implements ContainerRequestFilter
{
    @Override
    public void filter(ContainerRequestContext requestContext) throws IOException
    {
        //Obtain a CDI injected object by name
        UserService userService = (UserService) requestContext.getProperty("userService");
    }
}

perfect , well done

AWESOME! Thank you -- just what I needed.