docs: public File writeMap(Map<?, ?> map, LineSeparator lineSeparator, String kvSeparator, boolean isAppend) throws IORuntimeException {
  		if(null == kvSeparator) {
  			kvSeparator = " = ";
  		}
  		try(PrintWriter writer  = getPrintWriter(isAppend)) {
  			for (Entry<?, ?> entry : map.entrySet()) {
  				if (null != entry) {
  					writer.print(StrUtil.format("{}{}{}", entry.getKey(), kvSeparator, entry.getValue()));
  					printNewLine(writer, lineSeparator);
  					writer.flush();
  				}
  			}
  		}
  		return this.file;
  	}