code: public long getMetadataLastModified( String path )
          throws IOException, MetadataNotFoundException
      {
          Entry entry = backing.get(
              StringUtils.join( StringUtils.split( StringUtils.strip( path, "/" ), "/" ), "/" ) + "/maven-metadata.xml" );
          if ( !( entry instanceof FileEntry ) )
          {
              throw new MetadataNotFoundException( path );
          }
          return entry.getLastModified();
      }
docs: {@inheritDoc}