code: private String getImplicitGrantResponse(AuthorizationRequest authorizationRequest) {
          try {
              TokenRequest tokenRequest = requestFactory.createTokenRequest(authorizationRequest, "implicit");
              OAuth2Request storedOAuth2Request = requestFactory.createOAuth2Request(authorizationRequest);
              OAuth2AccessToken accessToken = getAccessTokenForImplicitGrant(tokenRequest, storedOAuth2Request);
              if (isNull(accessToken)) {
                  throw new UnsupportedResponseTypeException("Unsupported response type: token");
              }
              return appendAccessToken(authorizationRequest, accessToken);
          } catch (OAuth2Exception e) {
              return getUnsuccessfulRedirect(authorizationRequest, e, true);
          }
      }
docs: We can grant a token and return it with implicit approval.