for 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
}