//开始行,结束行,开始列,结束列
sheet.addMergedRegion(new CellRangeAddress(0, 0, 0, 3));
HSSFRow row = sheet.createRow(0);
HSSFCell cellHeader;
cellHeader = row.createCell(0);
//cellHeader.setCellStyle(style);
cellHeader.setCellValue("标题...");
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