@Override
    public void invokeHead(Map<Integer, ReadCellData<?>> headMap, AnalysisContext context) {
        invokeHeadMap(ConverterUtils.convertToStringMap(headMap, context), context);
    }
Receives the return of each piece of data parsed

@author jipengfei
fastexcel-core/src/main/java/cn/idev/excel/event/AnalysisEventListener.java