apache/hadoop · error · NoSuchElementException

No more entry in {f}

Error message

No more entry in {f}

What it means

The RemoteIterator<LocatedFileStatus> returned by listLocatedStatus wraps a plain listing iterator; calling next() after hasNext() returned false throws NoSuchElementException with the listed path ('No more entry in {f}'). This is ordinary iterator exhaustion, made easy to miss because RemoteIterator.next() declares IOException as well and loops often only catch that.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/AbstractFileSystem.java:1186

   * @throws UnresolvedLinkException unresolved link exception.
   * @throws IOException raised on errors performing I/O.
   * @return FileStatus Iterator.
   */
  public RemoteIterator<LocatedFileStatus> listLocatedStatus(final Path f)
      throws AccessControlException, FileNotFoundException,
      UnresolvedLinkException, IOException {
    return new RemoteIterator<LocatedFileStatus>() {
      private RemoteIterator<FileStatus> itor = listStatusIterator(f);
      
      @Override
      public boolean hasNext() throws IOException {
        return itor.hasNext();
      }
      
      @Override
      public LocatedFileStatus next() throws IOException {
        if (!hasNext()) {
          throw new NoSuchElementException("No more entry in " + f);
        }
        FileStatus result = itor.next();
        BlockLocation[] locs = null;
        if (result.isFile()) {
          locs = getFileBlockLocations(
              result.getPath(), 0, result.getLen());
        }
        return new LocatedFileStatus(result, locs);
      }
    };
  }

  /**
   * The specification of this method matches that of
   * {@link FileContext.Util#listStatus(Path)} except that Path f must be 
   * for this file system.
   * @param f the path.
   * @throws AccessControlException access control exception.

View on GitHub (pinned to 2add963021)

Solutions

1. Always guard consumption: while (it.hasNext()) { LocatedFileStatus s = it.next(); ... }
2. If an unguarded loop must be kept, catch NoSuchElementException separately from IOException as the termination signal
3. For small directories, prefer fc.util().listStatus(f) and iterate the returned array

Example fix

// before
while (true) {
  LocatedFileStatus s = itor.next(); // throws at end
  process(s);
}

// after
while (itor.hasNext()) {
  process(itor.next());
}

while (itor.hasNext()) {
  LocatedFileStatus s = itor.next();
  // process s
}

When it happens

Trigger: Calling next() without a preceding hasNext() check; do/while loops that consume next() first and test hasNext() afterwards; iteration helpers that assume next() returns null at the end instead of throwing.

Common situations: Hand-rolled listing loops ported from java.util.Iterator idioms; merging several RemoteIterators in one loop; input formats and directory walkers iterating large listings where exhaustion is the normal exit path.

Related errors

• No more items in iterator
• Attempted to seek or read past the end of the file
• No more items in iterator.
• No more elements
• Cannot rename symlink {src} to its target {dst}

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/25ae2cf8db509c8a. Report an issue: GitHub.