Java Programming

I have created a small application to upload any file and save it in a temporary directory.
Then display all the file names which are in that directory.here's my code ....

MultipartRequest mr = null;
try {
mr = new MultipartRequest(req, ".");
BufferedReader br = new BufferedReader(new FileReader(fileName = (String)mr.getFilesystemName("importFile")));

} catch(Exception e) { System.out.println("Error uploading from file '"+fileName+"': "+e); e.printStackTrace();
} finally { new File(fileName).delete(); }



String dir = "C:\\asta-timesheet\\temp\\";
Vector fileVector = new Vector();
boolean result = false;
DataInputStream dis;
FileInputStream fin;

try {
String fileContent = "";
Enumeration files = mr.getFileNames();

String name = (String)files.nextElement();
String filename = mr.getFilesystemName(name);
String type = mr.getContentType(name);
File f = mr.getFile(name);
FileReader fs = new FileReader(f);
BufferedReader in = new BufferedReader(fs);
String s, s2 = new String();
while((s = in.readLine())!= null) {
s2 += s + "\n";
}
fileContent = s2;


in.close();

File file = new File(dir, fileName);
// Create file if it does not exist
boolean success = file.createNewFile();
if (success) {
InputStream inn = new FileInputStream(f);
OutputStream out = new FileOutputStream(file);

// Transfer bytes from in to out
byte[] buf = new byte[1024];
int len;
while ((len = inn.read(buf)) > 0) {
out.write(buf, 0, len);
}
inn.close();
out.close();
} else {
// File already exists
req.setAttribute("fileStatus", "exists");
}

} catch(Exception e) { System.out.println("Error uploading from file '"+fileName+"': "+e); e.printStackTrace();}


File dirr = new File(dir);

String[] children = dirr.list();
if (children == null) {

} else {
for (int i=0; i<children.length; i++) {
String filename = children;

}
}

// The list of files can also be retrieved as File objects
File[] files = dirr.listFiles();

for (int i = 0; i < files.length; i++) {
File f = files[i];
}

req.setAttribute("fileVector", files);

return returnPage;


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I need help with opening up the listed files.i.e if its a word doc.i need it to be open on ms word.I have file types like excel,jpg,txt....Can someone pls explain or provide code for this.

thx in advance.