REST: CORSFilter

public class CORSFilter implements Filter {

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain fc) throws IOException, ServletException {
        HttpServletRequest httpReq = (HttpServletRequest) req;
        HttpServletResponse httpRes = (HttpServletResponse) res;
        httpRes.setHeader("Access-Control-Allow-Origin", "*");
        httpRes.setHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");

        String reqHead = httpReq.getHeader("Access-Control-Request-Headers");
        if(null != reqHead && !reqHead.isEmpty()){
                    httpRes.setHeader("Access-Control-Allow-Headers", reqHead);
                }

        fc.doFilter(req, res);
    }

    @Override
    public void init(FilterConfig fc) throws ServletException {
    }

    @Override
    public void destroy() {
    }



}