Java - get the newest file in a directory?

java file-io filesystems

109,130

Solution 1

The following code returns the last modified file or folder:

public static File getLastModified(String directoryFilePath)
{
    File directory = new File(directoryFilePath);
    File[] files = directory.listFiles(File::isFile);
    long lastModifiedTime = Long.MIN_VALUE;
    File chosenFile = null;

    if (files != null)
    {
        for (File file : files)
        {
            if (file.lastModified() > lastModifiedTime)
            {
                chosenFile = file;
                lastModifiedTime = file.lastModified();
            }
        }
    }

    return chosenFile;
}

Note that it required Java 8 or newer due to the lambda expression.

Solution 2

In Java 8:

Path dir = Paths.get("./path/somewhere");  // specify your directory

Optional<Path> lastFilePath = Files.list(dir)    // here we get the stream with full directory listing
    .filter(f -> !Files.isDirectory(f))  // exclude subdirectories from listing
    .max(Comparator.comparingLong(f -> f.toFile().lastModified()));  // finally get the last file using simple comparator by lastModified field

if ( lastFilePath.isPresent() ) // your folder may be empty
{
    // do your code here, lastFilePath contains all you need
}

Solution 3

This works perfectly fine for me:

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.comparator.LastModifiedFileComparator;
import org.apache.commons.io.filefilter.WildcardFileFilter;

...

/* Get the newest file for a specific extension */
public File getTheNewestFile(String filePath, String ext) {
    File theNewestFile = null;
    File dir = new File(filePath);
    FileFilter fileFilter = new WildcardFileFilter("*." + ext);
    File[] files = dir.listFiles(fileFilter);

    if (files.length > 0) {
        /** The newest file comes first **/
        Arrays.sort(files, LastModifiedFileComparator.LASTMODIFIED_REVERSE);
        theNewestFile = files[0];
    }

    return theNewestFile;
}

Solution 4

private File getLatestFilefromDir(String dirPath){
    File dir = new File(dirPath);
    File[] files = dir.listFiles();
    if (files == null || files.length == 0) {
        return null;
    }

    File lastModifiedFile = files[0];
    for (int i = 1; i < files.length; i++) {
       if (lastModifiedFile.lastModified() < files[i].lastModified()) {
           lastModifiedFile = files[i];
       }
    }
    return lastModifiedFile;
}

Solution 5

Something like:

import java.io.File;
import java.util.Arrays;
import java.util.Comparator;


public class Newest {
    public static void main(String[] args) {
        File dir = new File("C:\\your\\dir");
        File [] files  = dir.listFiles();
        Arrays.sort(files, new Comparator(){
            public int compare(Object o1, Object o2) {
                return compare( (File)o1, (File)o2);
            }
            private int compare( File f1, File f2){
                long result = f2.lastModified() - f1.lastModified();
                if( result > 0 ){
                    return 1;
                } else if( result < 0 ){
                    return -1;
                } else {
                    return 0;
                }
            }
        });
        System.out.println( Arrays.asList(files ));
    }
}

View more solutions

109,130

Author by

Admin

Updated on July 09, 2022

Comments

Admin almost 2 years

Does anybody have a snippet of Java that can return the newest file in a directory (or knowledge of a library that simplifies this sort of thing)?
Chris Conway over 15 years

It's kind of wonky to force a ClassCastException in the non-File case, instead of, say, asserting instanceof.
OscarRyz over 15 years

You won't get a non-File from the array returned by File.listFiles();
Zach Scrivena over 15 years

Remember to check that listFiles() doesn't return null.
andrej over 10 years

c'mon, you don't have to SORT array to get minimum value!
andrej over 10 years

c'mon, you don't have to SORT array to get minimum value!
mes over 9 years

Maybe perfect, but no fast
Cthulhu almost 9 years

Please don't just dump your code. Explain your train of thought so we can better understand your answer. Thanks.
Kiet Tran over 8 years

What happens if the difference between the two last-modified timestamps is larger than Integer.MAX_VALUE?
nilsmagnus over 8 years

There is a typo in your example: isPresented() should be isPresent()
Admin almost 8 years

Why don't you use new Comparator<File>()? This avoids the cast and the extra function.
Dileep over 7 years

What if we are not updating the directory it will give the same result every time.?
Prasanth V almost 7 years

guys you can use this code for get last modified file.
RaviSam over 3 years

is it possible without loading full files list? In cases when directory is too large.