private static String escapeFileSeparatorChar(String fname)
  {
    if (File.separatorChar == '\\')
    {
      return fname.replaceAll(File.separator + File.separator, "_");
    }
    else
    {
      return fname.replaceAll(File.separator, "_");
    }
  }
private static String escapeFileSeparatorChar ( String fname ) { if ( File . separatorChar == '\\' ) { return fname . replaceAll ( File . separator + File . separator , "_" ) ; } else { return fname . replaceAll ( File . separator , "_" ) ; } }
Escape file separator char to underscore. This prevents the file name
from using file path separator.

@param fname
@return escaped file name