private int calculateHeadSize(ReadSheetHolder readSheetHolder) {
        if (readSheetHolder.excelReadHeadProperty().getHeadMap().size() > 0) {
            return readSheetHolder.excelReadHeadProperty().getHeadMap().size();
        }
        if (readSheetHolder.getMaxNotEmptyDataHeadSize() != null) {
            return readSheetHolder.getMaxNotEmptyDataHeadSize();
        }
        return 0;
    }
Convert to the object the user needs

@author jipengfei
fastexcel-core/src/main/java/cn/idev/excel/read/listener/ModelBuildEventListener.java