Develop Reference

Getting MIME type of a File

I want to get mimetype of a file can anyone please help me
I want MIME Type like this...
File file=new File("example.jpeg");
String MimeTypeOfFile=/*files mimetype*/;
Thank You in Advance

You can use the Apache Tika Library: It detects and extracts metadata and text from over a thousand different file types
http://tika.apache.org/0.7/detection.html
It has various methods like extension checking or reading file data to detect mime-type. It would be easy and efficient rather than writing yourself.
Example :
System.out.println(new Tika().detect(new File(PATH_TO_FILE)));

saveAsHadoopFile - files extension

I'm using saveAsHadoopFile of JavaPairRDD to save RDD as avro file with snappy compression. Is it possible to force extension of output files to be snappy?

AvroOutputFormat has hardcoded .avro extension and does not allow to change it.
I've uploaded a patch to the Avro JIRA with proper changes.
If you have similar problem you have to (as for now) simply subclass AvroOutputFormat and use it in saveAsHadoopFile method. For example in Scala:
rdd.saveAsHadoopFile("output/path",
classOf[AvroWrapper[GenericRecord]],
classOf[NullWritable],
classOf[YourOutputFormatClassName[GenericRecord]])

PCL Format generation from pdf in java

I want to export jasperreport report in pcl format , but i didn't find a way to do it , so i generated in pdf .
I want to create a class that convert this pdf to PCL5 format. So please can you give me a sarting point and suggetions .
Thank you in advance,

I don't there are any products left that will export any level of PCL. Print to a PCL driver, but not directly export it.
You can use any PCL5 driver with Acrobat to print to FILE: And, there are many products that will batch print PDF's.
However, a lot depends on what you expect to do with the PCL5? And, why?
Bob Pooley
bp#pagetech.com

Get real file extension -Java code

I would like to determine real file extension for security reason.
How can I do that?

Supposing you really mean to get the true content type of a file (ie it's MIME type) you should refer to this excellent answer.
You can get the true content type of a file in Java using the following code:
File file = new File("filename.asgdsag");
InputStream is = new BufferedInputStream(new FileInputStream(file));
String mimeType = URLConnection.guessContentTypeFromStream(is);

There are a number of ways that you can do this, some more complicated (and more reliable) than others. The page I linked to discusses quite a few of these approaches.

Not sure exactly what you mean, but however you do this it is only going to work for the specific set of file formats which are known to you
you could exclude executables (are you talking windows here?) - there's some file header information here http://support.microsoft.com/kb/65122 - you could scan and block files which look like they have an exe header - is this getting close to what you mean when you say 'real file extension'?

Running a JavaScript command from MATLAB to fetch a PDF file

I'm currently writing some MATLAB code to interact with my company's internal reports database. So far I can access the HTML abstract page using code which looks like this:
import com.mathworks.mde.desk.*;
wb=com.mathworks.mde.webbrowser.WebBrowser.createBrowser;
wb.setCurrentLocation(ReportURL(8:end));
pause(1);
s={};
while isempty(s)
s=char(wb.getHtmlText);
pause(.1);
end
desk=MLDesktop.getInstance;
desk.removeClient(wb);
I can extract out various bits of information from the HTML text which ends up in the variable s, however the PDF of the report is accessed via what I believe is a JavaScript command (onClick="gotoFulltext('','[Report Number]')").
Any ideas as to how I execute this JavaScript command and get the contents of the PDF file into a MATLAB variable?
(MATLAB sits on top of Java, so I believe a Java solution would work...)

I think you should take a look at the JavaScript that is being called and see what the final request to the webserver looks like.
You can do this quite easily in Firefox using the FireBug plugin.
https://addons.mozilla.org/en-US/firefox/addon/1843
Once you have found the real server request then you can just request this URL or post to this URL instead of trying to run the JavaScript.

Once you have gotten the correct URL (a la the answer from pjp), your next problem is to "get the contents of the PDF file into a MATLAB variable". Whether or not this is possible may depend on what you mean by "contents"...
If you want to get the raw data in the PDF file, I don't think there is a way currently to do this in MATLAB. The URLREAD function was the first thing I thought of to read content from a URL into a string, but it has this note in the documentation:
s = urlread('url') reads the content
at a URL into the string s. If the
server returns binary data, s will
be unreadable.
Indeed, if you try to read a PDF as in the following example, s contains some text intermingled with mostly garbage:
s = urlread('http://samplepdf.com/sample.pdf');
If you want to get the text from the PDF file, you have some options. First, you can use URLWRITE to save the contents of the URL to a file:
urlwrite('http://samplepdf.com/sample.pdf','temp.pdf');
Then you should be able to use one of two submissions on The MathWorks File Exchange to extract the text from the PDF:
Extract text from a PDF document by Dimitri Shvorob
PDF Reader by Tom Gaudette
If you simply want to view the PDF, you can just open it in Adobe Acrobat with the OPEN function:
open('temp.pdf');

wb=com.mathworks.mde.webbrowser.WebBrowser.createBrowser;
wb.executeScript('javascript:alert(''Some code from a link'')');
desk=com.mathworks.mde.desk.MLDesktop.getInstance;
desk.removeClient(wb);