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Auto-Detect File Extension with APACHE JENA

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);
https://jena.apache.org/documentation/io/rdf-input.html

Save embedded files from .xls document (Apache POI)

I would like to save all attached files from an Excel (xls/HSSF) without extension.
I've been trying for a long time now, and I really don't know if this is even possible. I also tried Apache Tika, but I don't want to use Tika for this, because I need POI for other tasks, anyway.
I tried the sample code from the Busy Developers Guide, but this does not extract files in the old office format (doc, ppt, xls). And it throws an Error when trying to create new SlideShow(new HSLFSlideShow(dn, fs)) Error: (Remove argument to match HSLFSlideShow(dn))
My actual code is:
public static void saveEmbeddedXLS(InputStream fis_param, String embDIR) throws IOException, InvalidFormatException{
//HSSF - XLS
int i = 0;
System.out.println("Starting Embedded Search in xls...");
POIFSFileSystem fs = new POIFSFileSystem(fis_param);//create FileSystem using fileInputStream
HSSFWorkbook workbook = new HSSFWorkbook(fs);
for (HSSFObjectData obj : workbook.getAllEmbeddedObjects()) {
System.out.println("Objects : "+ obj.getOLE2ClassName());//the OLE2 Class Name of the object
String oleName = obj.getOLE2ClassName();//Document Type
DirectoryNode dn = (DirectoryNode) obj.getDirectory();//get Directory Node
//Trying to create an input Stream with the embedded document, argument of createDocumentInputStream should be: String; Where/How can I get this correct parameter for the function?
InputStream is = dn.createDocumentInputStream(dn);//This line is incorrect! How can I do i correctly?
FileOutputStream fos = new FileOutputStream("embDIR" + i);//Outputfilepath + Number
IOUtils.copy(is, fos);//FileInputStream > FileOutput Stream (save File without extension)
i++;
}
}
So my simple question is:
Is it possible to save ALL attachments from an xls file without any extension (as simple as possible)? And can any one provide me a solution? Many Thanks!

trying to pass fileinputstream obj from function into another function

I would like to use a function to read from a properties file and than use the object of that file at various places.here is what I have tried so far with no luck.
public class all_the_functions
{
public FileInputStream loadPropertiesFile(FileInputStream obj2) throws IOException
{
//reading from the properties file
Properties obj = new Properties();
FileInputStream fileobj = new FileInputStream("//Users//macuser//Desktop//selenium//project_Mat//input_properties.properties");
obj.load(fileobj);
return fileobj;
}
}
And than in my main function I am using the following code
public class searchdynamic();
{
FileInputStream Obj;
all_the_functions func = new all_the_functions();
func.loadPropertiesFile(Obj);
WebDriver driver = new FirefoxDriver();
driver.navigate().to(Obj.getproperty("valid URL");
}
The end goal is to read from. The input file by using the function and stroung the properties file so that I can always call the same function when I need to read from the file. Can someone please point me to what I am doing wrong here.
Thanks.

Can u try this
public class searchdynamic();
{
FileInputStream Obj;
all_the_functions func = new all_the_functions();
Obj=func.loadPropertiesFile(Obj);
WebDriver driver = new FirefoxDriver();
driver.navigate().to(Obj.getproperty("valid URL");
}

What is the string that your property is returning? "http://www..."
In theory, this should work (although I'm used to webdriver being navigate().GoToUrl(string url). Give that a shot...
Also, friendly warning about this being not oop or compiling. Might be a good idea to tie your properties to values somehow. I understand this is a keyword driven framework, but it is better practice to have a user input "Google" and have your code digest that into something like
driver.Navigate().GoToUrl("http://google.com"); // (c#)
This way, you can count on correct input and handle incorrect input appropriately.
Regardless, try .Navigate().GoToUrl()

How to convert HttpPostedFileBase file to Java.Io.InputStream?

I'm working on ASP.net with the MPXJ library. The .net version of MPXJ has been created using IKVM.
Currently, I have a big problem: After upload a file (Microsoft Project file - .mpp file) to server (I don't need to save it), I want to convert from HttpPostedFileBase to the IKVM version of java.io.InputStream and MPXJ will manipulate them, but I don't know a way to implement this.
My code:
public ActionResult Upload(HttpPostedFileBase files)
{
// Todo: Convert from HttpPostedFileBase to Java.Io.InputStream
ProjectReader reader = new MPPReader();
ProjectFile projectObj = reader.read(Java.Io.InputStream);
}

You need a wrapper to provide a conversion between the IKVM Java type java.io.InputStream and a .net Stream instance. As luck would have it, IKVM ships with one...
Using the wrapper, your example will now look like this:
public ActionResult Upload(HttpPostedFileBase files)
{
ProjectReader reader = new MPPReader();
ProjectFile projectObj = reader.read(new ikvm.io.InputStreamWrapper(files.InputStream));
}

If you don't want to use IKVM, you can implement as below:
public ActionResult Upload(HttpPostedFileBase files)
{
byte[] fileData = null;
using (var binaryReader = new BinaryReader(files.InputStream))
{
fileData = binaryReader.ReadBytes(files.ContentLength);
}
ProjectFile projectObj = reader.read(new ByteArrayInputStream(fileData));
}

JXL library call

i am a barely new to the java (was always on c# before) and need to create a swing application where i need to read a data from xls file. So i use jXL.
I have a class, which returns name of a first sheet from excel file, choosen in jFileChooser. Here is the code:
import java.io.File;
import jxl.Sheet;
import jxl.Workbook;
public class ExcelObject
{
private String filename = null;
private Workbook wb = null;
private Sheet sheet = null;
public ExcelObject(String f)
{
filename = f;
}
public String getSheetName()
{
String sheet_name = null;
try
{
wb = Workbook.getWorkbook(new File(filename));
sheet = wb.getSheet(0);
sheet_name = sheet.getName();
}
catch (Exception e)
{
e.printStackTrace();
}
finally
{
wb.close();
}
return sheet_name;
}
}
in the program call looks like :
ExcelObject ex = new ExcelObject(filename);
String s = ex.getSheetName();
lblReport.setText(s);
So the issue is : when ran in the eclipse (3.4.2) i am getting a correct value, when jar is compiled, NO VALUE IS RETURNED! I mean lblReport is empty, with no exceptions and warnings.
Keep in mind : all other external jars work fine.
I tried a lot of things but none is working.
Also, if i do something like
ExcelObject ex = new ExcelObject(filename);
String s = ex.getSheetName();
// lblReportRun.setText(s);
lblReportRun.setText("Test");
lblAnyOtherLabel.setText("Test");
no text is displayed in the labels either, in compiled jar, and fine in eclipse.

This is probably because if some exception occurs when opening the workbook, you catch it, print the stack trace, and then close the workbook in the finally block. But since an exception occurred when calling Workbook.getWorkbook, the wb variable is still null, and you're trying to invoke close on it. So a NullPointerException happens while in the finally block.
Watch your console, you must have some exception popping up.
Also, note that fileName should be the only instance variable of your class, that Java variable normally don't contain underscores and use camelCase, and thet the fileName variable should be of type File, rather than String : you get a File from the file chooser, transform it into a string, and then transform it back to a File.
Another possibility, since it works in Eclipse and not when run externally, is that you forgot to put the jXL jar in the classpath, which causes some ClassNotFoundException when trying to use the ExcelObject class.