private static Provider validateProvider(Provider provider) {
        Set<String> ids = provider.getAvailableIDs();
        if (ids == null || ids.size() == 0) {
            throw new IllegalArgumentException("The provider doesn't have any available ids");
        }
        if (!ids.contains("UTC")) {
            throw new IllegalArgumentException("The provider doesn't support UTC");
        }
        if (!UTC.equals(provider.getZone("UTC"))) {
            throw new IllegalArgumentException("Invalid UTC zone provided");
        }
        return provider;
    }
private static Provider validateProvider ( Provider provider ) { Set < String > ids = provider . getAvailableIDs ( ) ; if ( ids == null || ids . size ( ) == 0 ) { throw new IllegalArgumentException ( "The provider doesn't have any available ids" ) ; } if ( ! ids . contains ( "UTC" ) ) { throw new IllegalArgumentException ( "The provider doesn't support UTC" ) ; } if ( ! UTC . equals ( provider . getZone ( "UTC" ) ) ) { throw new IllegalArgumentException ( "Invalid UTC zone provided" ) ; } return provider ; }
Sets the zone provider factory without performing the security check.

@param provider  provider to use, or null for default
@return the provider
@throws IllegalArgumentException if the provider is invalid