public T relativeHeadRowIndex(Integer relativeHeadRowIndex) {
        parameter().setRelativeHeadRowIndex(relativeHeadRowIndex);
        return self();
    }
Writes the head relative to the existing contents of the sheet. Indexes are zero-based.

@param relativeHeadRowIndex
@return
fastexcel-core/src/main/java/cn/idev/excel/write/builder/AbstractExcelWriterParameterBuilder.java