How do I iterate through the files in a directory in Java?

Question

I need to get a list of all the files in a directory, including files in all the sub-directories. What is the standard way to accomplish directory iteration with Java?

Answer 1

For Java 7+, there is also https://docs.oracle.com/javase/7/docs/api/java/nio/file/DirectoryStream.html

Example taken from the Javadoc:

List listSourceFiles(Path dir) throws IOException {
   List result = new ArrayList<>();
   try (DirectoryStream stream = Files.newDirectoryStream(dir, "*.{c,h,cpp,hpp,java}")) {
       for (Path entry: stream) {
           result.add(entry);
       }
   } catch (DirectoryIteratorException ex) {
       // I/O error encounted during the iteration, the cause is an IOException
       throw ex.getCause();
   }
   return result;
}