ignore blank request parameters

HackedParametersProvider.java

@Component
public class HackedParametersProvider extends OgnlParametersProvider {
    public HackedParametersProvider(...., HttpServletRequest request, ...) {
        super(....., new HackedRequest(request), ....);
    }
}

HackedRequest.java

import com.google.common.base.Strings;
import com.google.common.collect.Maps;
import com.google.common.base.Predicate;

public class HackedRequest extends HttpServletRequestWrapper {
    public HackedRequest(HttpServletRequest request) {
         super(request);
    }

    @Override
    public Enumeration getParameterNames() { //ignores blank parameters
        Set<String> names = new HashSet<String>();
        Enumeration<String> superNames = super.getParameterNames();
        while (superNames.hasMoreElements()) {
            String name = superNames.nextElement();
            if (!Strings.isNullOrEmpty(getParameter(name))) {
                names.add(name);
            }
        }
        return Collections.enumeration(names);
    }

    @Override
    public Map getParameterMap() {
        return Maps.filterKeys(super.getParameterMap(), new Predicate<String>() {
                   public boolean apply(String name) {
                        return !Strings.isNullOrEmpty(getParameter(name));
                   }
              });
    }
}