Program: 31897
Project: 31897
Buggy source:
@JsonIgnore public List<String> getAllMetaColumns(ModelConfig modelConfig) throws IOException {
  if (metaColumns == null) {
synchronized (this) {
      if (metaColumns == null) {
        PathFinder pathFinder=new PathFinder(modelConfig);
        List<String> scoreMetaColumns=null;
        if (StringUtils.isNotBlank(scoreMetaColumnNameFile) && SourceType.HDFS.equals(dataSet.getSource())) {
          String path=scoreMetaColumnNameFile;
          File file=new File(scoreMetaColumnNameFile);
          path=new Path(pathFinder.getEvalSetPath(this),file.getName()).toString();
          scoreMetaColumns=CommonUtils.readConfFileIntoList(path,dataSet.getSource(),dataSet.getHeaderDelimiter());
          metaColumns=scoreMetaColumns;
        }
        if (StringUtils.isNotBlank(dataSet.getMetaColumnNameFile())) {
          String rawMetaPath=dataSet.getMetaColumnNameFile();
          if (StringUtils.isNotBlank(rawMetaPath) && SourceType.HDFS.equals(dataSet.getSource())) {
            File file=new File(rawMetaPath);
            rawMetaPath=new Path(pathFinder.getEvalSetPath(this),file.getName()).toString();
          }
          List<String> rawMetaColumns=CommonUtils.readConfFileIntoList(rawMetaPath,dataSet.getSource(),dataSet.getHeaderDelimiter());
          if (metaColumns != null) {
            for (            String column : rawMetaColumns) {
              if (!metaColumns.contains(column)) {
                metaColumns.add(column);
              }
            }
          }
 else {
            metaColumns=rawMetaColumns;
          }
        }
      }
    }
  }
  return metaColumns;
}

Fixed version (ground truth):
@JsonIgnore public List<String> getAllMetaColumns(ModelConfig modelConfig) throws IOException {
  if (metaColumns == null) {
synchronized (this) {
      if (metaColumns == null) {
        PathFinder pathFinder=new PathFinder(modelConfig);
        List<String> scoreMetaColumns=null;
        if (StringUtils.isNotBlank(scoreMetaColumnNameFile) && SourceType.HDFS.equals(dataSet.getSource())) {
          String path=scoreMetaColumnNameFile;
          File file=new File(scoreMetaColumnNameFile);
          path=new Path(pathFinder.getEvalSetPath(this),file.getName()).toString();
          scoreMetaColumns=CommonUtils.readConfFileIntoList(path,dataSet.getSource(),StringUtils.isBlank(dataSet.getHeaderDelimiter()) ? dataSet.getDataDelimiter() : dataSet.getHeaderDelimiter());
          metaColumns=scoreMetaColumns;
        }
        if (StringUtils.isNotBlank(dataSet.getMetaColumnNameFile())) {
          String rawMetaPath=dataSet.getMetaColumnNameFile();
          if (StringUtils.isNotBlank(rawMetaPath) && SourceType.HDFS.equals(dataSet.getSource())) {
            File file=new File(rawMetaPath);
            rawMetaPath=new Path(pathFinder.getEvalSetPath(this),file.getName()).toString();
          }
          List<String> rawMetaColumns=CommonUtils.readConfFileIntoList(rawMetaPath,dataSet.getSource(),StringUtils.isBlank(dataSet.getHeaderDelimiter()) ? dataSet.getDataDelimiter() : dataSet.getHeaderDelimiter());
          if (metaColumns != null) {
            for (            String column : rawMetaColumns) {
              if (!metaColumns.contains(column)) {
                metaColumns.add(column);
              }
            }
          }
 else {
            metaColumns=rawMetaColumns;
          }
        }
      }
    }
  }
  return metaColumns;
}