public boolean validate() {
      boolean rc = true;

      if (alias == null || alias.isEmpty()) {
        System.out.println("There is no alias specified. Please provide the" +
                "mandatory <alias>. See the usage description with -help.");
        rc = false;
      }

      if (provider == null) {
        System.out.println("There are no valid CredentialProviders configured." +
                "\nCredential will not be created.\n"
                + "Consider using the -provider option to indicate the provider" +
                " to use.");
        rc = false;
      }

      return rc;
    }
Validates the user input.

@return - True if inputs are valid. False otherwise.
ambari-server/src/main/java/org/apache/ambari/server/credentialapi/CredentialUtil.java