@Override
    protected Event doExecuteInternal(final RequestContext requestContext) {
        val username = requestContext.getRequestParameters().get("username");
        WebUtils.putCredential(requestContext, new UsernamePasswordCredential(username, null));
        WebUtils.putGraphicalUserAuthenticationUsername(requestContext, username);
        return success();
    }
This is {@link AcceptUserGraphicsForAuthenticationAction}.

@author Misagh Moayyed
@since 5.1.0
support/cas-server-support-gua/src/main/java/org/apereo/cas/web/flow/AcceptUserGraphicsForAuthenticationAction.java