private Optional<DocumentType> getDocumentTypeFromURI(String fileURI) {
        int dotIndex = fileURI.lastIndexOf('.');
        String fileExtension = fileURI.substring(dotIndex + 1).toLowerCase();

        DocumentType documentType = fileExtensions.get(fileExtension);
        if (documentType == null) return Optional.empty();
        return Optional.of(documentType);
    }
Class responsible for maintaining the set of open documents and reparsing them.
When {@link SchemaDocumentScheduler#updateFile} is called, it will call {@link DocumentManager#updateFileContent} on the appropriate file 
and also other files that may have dependencies on the contents of the file.
integration/schema-language-server/language-server/src/main/java/ai/vespa/schemals/schemadocument/SchemaDocumentScheduler.java