* @throws InvalidNamespaceException if the namespace is invalid
* @throws VersionException the if the version does not fit the expected range
*/
protected void verifyNamespaceUri( @Nullable @NonNls String namespaceURI ) throws InvalidNamespaceException, VersionException {
if ( namespaceURI == null || namespaceURI.trim().length() == 0 ) {
throw new VersionException( "No version information available" );
}
String expectedBase = getNameSpaceUriBase();
if ( !namespaceURI.startsWith( expectedBase ) ) {
throw new InvalidNamespaceException( namespaceURI, expectedBase + "/$VERSION>" );
}