Select Correct Text File - Names Changing

Question

Eevery few hours my AS400 generates a text file. I am writing a program that will automatically take this file and convert it to an XML. The problem I am having is with the naming convention of the text file:
"IR + 6 digit number which increments by one each time a file is generated + _ + The start date and time for the file +_to_ + end date and time for the file + .txt". For example IR000002_20070528141515_to_20070528170003.txt is the name of the second file generated which started at 14:15:15 on 28/05/2007 and ended at 17:00:03 on 28/05/2007.
Each time my program runs I want it to read the latest file that has been generated. I know where the file will be found and how to select the file when it is generated with the same name each time but havnt a clue now that each file has a different name. Can anybody help? Can I use JFileChooser?

Answer 1

You can use the lastModified() method of the File object to your benefit:
import java.io.File;
public class FindLatestFile {
        public static File getLatest(File thisDir) throws Exception {
                long latestModDate = -1;
                File latestFile = null;
                if (!thisDir.isDirectory()) {
                        throw new Exception("Please pass in a directory.");
                File[] fileList = thisDir.listFiles();
                for (File f : fileList) {
                        if (f.lastModified() > latestModDate) {
                                latestModDate = f.lastModified();
                                latestFile = f;
                return latestFile;
        public static void main(String[] args) {
                try {
                        System.out.println("The latest file in the current directory is " +
                                        getLatest( new File(System.getProperty("user.dir") ) ) + ".");
                } catch (Exception e) {
                        e.printStackTrace();
}