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Hello, I would like to know how can I ready query parameters from URL using liferay filter?I am working on integrating my liferay application to Authorization server.  I created a filter and redirect to Auth server. I  was presented the Auth server login page for username and password. Once my log username and password successful an redirect of the URL was displayed with the authorization code as query parameter http://localhost:8081/?code=xF0ea_MIwT4cQk0lFThTYQtRfopJAW78V_ZxNz_q. I would like to get this authorization code from the URL so I can make POST call to Authorization server to receive a JSON token and then once I get the token display the dashboard.  I tried to use liferay portal utility class ParmUtil but that didn't  work. Here is my code snippet below:

@Component(
    immediate = true,
    property = {
               "servlet-context-name=",
               "servlet-filter-name=Oauth2 Login Filter",
               "url-pattern=/c/portal/login"
    },
    service = Filter.class
)
public class AuthenticationSSOFilter implements Filter {
    
    private static final Log _log = LogFactoryUtil.getLog(AuthenticationSSOFilter.class);
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        // TODO Auto-generated method stub
        
    }    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
            throws IOException, ServletException {
    
        
    try {    
          HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
          HttpServletResponse response = (HttpServletResponse) servletResponse;

 Response clientResponse =   ClientBuilder.newClient().target(OauthBaseDEVUrl)
 if (clientResponse.getStatus() == 302){
           response.sendRedirect(OauthBaseDEVUrl);
 String actuallRedirectValue = ParamUtil.getString(httpServletRequest,"code");
             _log.info("Actual Redirect Param Value:" + actuallRedirectValue);
     }
        
    } catch (Exception e) {
          _log.error("Error in LoginFilter: " + e.getMessage(), e);
          } finally {
             filterChain.doFilter(servletRequest, servletResponse);
          }
}    @Override
    public void destroy() {
        // TODO Auto-generated method stub
        
    }
    
}