@Override public String initialize(){
  m_Current=0;
  for (  File dataset : m_Datasets) {
    if (!dataset.exists())     return "Dataset does not exist: " + dataset;
    if (dataset.isDirectory())     return "Dataset points to a directory: " + dataset;
  }
  return null;
}

@ Override public String initialize ( ) { m_Current = 0 ; for ( File dataset : m_Datasets ) { if ( ! dataset . exists ( ) ) return "Dataset does not exist: " + dataset ; if ( dataset . isDirectory ( ) ) return "Dataset points to a directory: " + dataset ; } return null ; }
initializes the provider to start providing datasets from scratch .
