private function getHeaderLine($columnMetrics)
{
foreach ($columnMetrics as $index => $value) {
if (in_array($value, $this->unsupportedColumns)) {
unset($columnMetrics[$index]);
}
}
if ($this->translateColumnNames) {
$columnMetrics = $this->translateColumnNames($columnMetrics);
}
foreach ($columnMetrics as &$value) {
$value = $this->formatValue($value);
}
return implode($this->separator, $columnMetrics);
}