@Override
public String getAuthorizationUrl(String responseType, String apiKey, String callback, String scope, String state,
Map<String, String> additionalParams) {
CommonHelper.assertNotBlank("callback", callback,
"Must provide a valid url as callback. PayPal does not support OOB");
if (additionalParams == null) {
additionalParams = new HashMap<>();
}
final String nonce = System.currentTimeMillis() + CommonHelper.randomString(10);
additionalParams.put("nonce", nonce);
return super.getAuthorizationUrl(responseType, apiKey, callback, scope, state, additionalParams);
}