[HBASE-16529] PathFilter accept implementations must be exception free

• Type: Umbrella
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Vladimir Rodionov
• Created: 30/Aug/16 04:21
• Updated: 30/Aug/16 06:39

Description

As an example of a wrong PathFilter implementation:

FSUtils.ReferenceFileFilter

    @Override
    protected boolean accept(Path p, @CheckForNull Boolean isDir) {
      if (!StoreFileInfo.isReference(p)) {
        return false;
      }

      try {
        // only files can be references.
        return isFile(fs, isDir, p);
      } catch (IOException ioe) {
        // Maybe the file was moved or the fs was disconnected.
        LOG.warn("Skipping file " + p +" due to IOException", ioe);
        return false;
      }
    }

That is wrong. We can't say if path passes the filter or not if Exception is thrown. The general rule: DO NOT USE ANY CALLS WHICH MAY THROW EXCEPTION INSIDE ACCEPT METHOD IMPLEMENTATION.

See HBASE-16527.

FSUtils contains several path filters for starter.