I want to convert any file extension to .ttl (TURTLE) and I need to use Apache Jena, I am aware of how it can be accomplished using RDFJ4 but the output isn't as accurate as it is using Jena. I want to know how I can auto-detect the extension or rather file type if I am not aware of the extension when reading a file from a directory. This is my code when I hardcode the file-name, it works, I just need help in auto detecting the file type. My code is as follows:
public class Converter {
public static void main(String[] args) throws FileNotFoundException {
String fileName = "./abc.rdf";
Model model = ModelFactory.createDefaultModel();
//I know this is how it is done with RDF4J but I need to use Apache Jena.
/* RDFParser rdfParser = Rio.createParser(Rio.getWriterFormatForFileName(fileName).orElse(RDFFormat.RDFXML));
RDFWriter rdfWriter = Rio.createWriter(RDFFormat.TURTLE,
new FileOutputStream("./"+stripExtension(fileName)+".ttl"));*/
InputStream is = FileManager.get().open(fileName);
if (is != null) {
model.read(is, null, "RDF/XML");
model.write(new FileOutputStream("./converted.ttl"), "TURTLE");
} else {
System.err.println("cannot read " + fileName);
}
}
}
All help and advice will be highly appreciated.
There is functionality that handles reading from a file using the extension to determine the syntax:
RDFDataMgr.read(model, fileName);
It also handles compressed files e.g. "file.ttl.gz".
There is a registry of languages:
RDFLanguages.fileExtToLang(...)
RDFLanguages.filenameToLang(...)
For more control see RDFParser:
RDFParser.create().
source(FileName)
... many options including forcing the language ...
.parse(model);