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

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));
}

Related

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

How to convert Scala FilePart as File (Java) to use in multipart-form data?

I have a method that already have an FilePart[TemporaryFile] and i will call another method to send a multi-part form data. This method is using scala play 2.4.X and i have to send it using ning method below:
def sendFile(file: FilePart[TemporaryFile]): Option[Future[Unit]] = {
val asyncHttpClient:AsyncHttpClient = WS.client.underlying
val postBuilder = asyncHttpClient.preparePost(s"${config.ocrProvider.host}")
val multiPartPost = postBuilder
.addBodyPart(new StringPart("access_token",s"${config.ocrProvider.accessToken}"))
.addBodyPart(new StringPart("typename",s"${config.ocrProvider.typeName}"))
.addBodyPart(new StringPart("action",s"${config.ocrProvider.actionUpload}"))
.addBodyPart(new FilePart(**expects java.io.File not FilePart**)
}
How can i take advantage of this parameter and send as java.io.File?
You need to write the content of file: FilePart[TemporaryFile] to disk and then use that file for constructing the new multipart request. You can see this example Scala File Upload
val tempFile = new File("/tmp/some/path")
file.ref.moveTo(tempFile)
val filePart = new FilePart(tempFile)

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!

Aspose with RJB (Ruby Java Bridge) is not working

I have a code in Java that opens a excel template by aspose library (it runs perfectly):
import com.aspose.cells.*;
import java.io.*;
public class test
{
public static void main(String[] args) throws Exception
{
System.setProperty("java.awt.headless", "true");
FileInputStream fstream = new FileInputStream("/home/vmlellis/Testes/aspose-cells/template.xlsx");
Workbook workbook = new Workbook(fstream);
workbook.save("final.xlsx");
}
}
After I run this on Ruby with RJB (Ruby Java Bridge):
require 'rjb'
#RJM Loading
JARS = Dir.glob('./jars/*.jar').join(':')
print JARS
Rjb::load(JARS, ['-Xmx512M'])
system = Rjb::import('java.lang.System')
file_input = Rjb::import('java.io.File')
file_input_stream = Rjb::import('java.io.FileInputStream')
workbook = Rjb::import('com.aspose.cells.Workbook')
system.setProperty("java.awt.headless", "true")
file_path = "/home/vmlellis/Testes/aspose-cells/template.xlsx"
file = file_input.new(file_path)
fin = file_input_stream.new(file)
wb = workbook.new(fin)
I get this error:
test.rb:57:in `new': Can't find file: java.io.FileInputStream#693a317a. (FileNotFoundException)
from aspose-test.rb:57:in `<main>'
Why? I run the same code... but in Ruby is not working! How do I fix this?
Update:
In documentation there is the the initializer: Workbook(java.io.InputStreamstream)... but it's not working in RJB. (How is this possible?)
Your program should have worked, but I could not find any reason why it didn't and I am looking into it.
Now the alternate approaches.
Approach 1
Use Workbook(String) constructor instead of Workbook(FileInputStream). This worked flawlessly at my end. The sample code is
require 'rjb'
#RJM Loading
JARS = Dir.glob('/home/saqib/cellslib/*.jar').join(':')
print JARS
Rjb::load(JARS, ['-Xmx512M'])
system = Rjb::import('java.lang.System')
workbook = Rjb::import('com.aspose.cells.Workbook')
system.setProperty("java.awt.headless", "true")
file_path = "/home/saqib/rjb/template.xlsx"
save_path = "/home/saqib/rjb/final.xlsx"
wb = workbook.new(file_path)
wb.save(save_path)
Approach 2
Write a new Java class library. Write all your Aspose.Cells related code in it. Expose very simple and basic methods that needs to be called from Ruby (RJB).
Why?
It is easy to write program in native Java language. If you use RJB, you need to perform a lot of code conversions
It is easy to debug and test in Java.
Usage of RJB will only be limited to calling methods from your own Java library. The RJB code will be small and basic.
Similar Example using own library
Create a new Java project, lets say "cellstest". Add a new public class in it.
package cellstest;
import com.aspose.cells.Workbook;
public class AsposeCellsUtil
{
public String doSomeOpOnWorkbook(String inFile, String outFile)
{
String result = "";
try
{
// Load the workbook
Workbook wb = new Workbook(inFile);
// Do some operation with this workbook
// ..................
// Save the workbook
wb.save(outFile);
// everything ok.
result = "ok";
}
catch(Exception ex)
{
// Return the exception to calling program
result = ex.toString();
}
return result;
}
}
Like this, add as many methods as you like, for each operation.
Build the project and copy the "cellstest.jar" in same folder where you copied Aspose.Cells jar files. You can return a String from your methods and check the return value in Ruby program for success or error code. The Ruby program will now be like
require 'rjb'
#RJM Loading
JARS = Dir.glob('/home/saqib/cellslib/*.jar').join(':')
print JARS
Rjb::load(JARS, ['-Xmx512M'])
system = Rjb::import('java.lang.System')
AsposeCellsUtil = Rjb::import('cellstest.AsposeCellsUtil')
system.setProperty("java.awt.headless", "true")
file_path = "/home/saqib/rjb/template.xlsx"
save_path = "/home/saqib/rjb/final.xlsx"
# initialize instance
asposeCellsUtil = AsposeCellsUtil.new()
# call methods
result = asposeCellsUtil.doSomeOpOnWorkbook(file_path, save_path)
puts result
PS. I work for Aspose as Developer Evangelist.
In your Java code, you pass a file name string into FileInputStream() constructor:
FileInputStream fstream = new FileInputStream("/home/vmlellis/Testes/aspose-cells/template.xlsx");
In your Ruby code, you pass a file object:
file = file_input.new(file_path)
fin = file_input_stream.new(file)
Have you tried to do the same thing as in Java?
fin = file_input_stream.new(file_path)

Access file in WebContent folder from a servlet

I'm trying to generate a PDF document using FOP. The pdf generation code is kept in a servlet and the xsl is in a specific folder in the WebContent folder.
How can I access this xsl file by giving a relative path? It works only if I give the complete path in the File object.
I need to generate the xml content dynamically. How can I give this dynamically generated xml as the source instead of a File object?
Please provide your suggestions.
To get the path you can just do:
String path = s.getServletContext().getRealPath("/WEB-INF/somedir/hdfeeh");
s is the class that implements HTTPServlet.You can also use this.getServletContext() if its your servlet class.
Then pass this as a parameter.
As far as using dynamically generated XML, the library you're using should support using an input stream, write your XML, convert it to a byte array, then wrap it in a ByteArrayInputStream and use this.
For a direct and independent container implementation, you can access the resourcewith the following method getResource() inside your servlet:
/start servlet/
public InputStream getResource(String resourcePath) {
ServletContext servletContext = getServletContext();
InputStream openStream = servletContext.getResourceAsStream( resourcePath );
return openStream;
}
public void testConsume() {
String path = "WEB-INF/teste.log";
InputStream openStream = getResource( path );
int c = -1;
byte[] bb = new byte[1024];
while ( -1 != ( c = openStream.read( bb ) ) ) {
/* consume stream */
}
openStream.close();
}
/end servlet/
I used the following method to read the file under web content
BufferedReader reader = new BufferedReader(new InputStreamReader(request.getSession().getServletContext().getResourceAsStream("/json/sampleJson.json")));
Now all the file content is available in the reader object.

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