poi-导出Excel

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最新poi的jar包。与之前版本存在样式设置区别

<!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.17</version>
</dependency>

        //创建工作簿workbook
        //利用工作簿对象创建工作表sheet
        //利用工作表对象创建行row
        //利用行对象创建单元格对象cell
        HSSFWorkbook wb= new HSSFWorkbook(); //创建工作薄
        HSSFSheet sheet=wb.createSheet(); //利用工作薄创建工作表
//      表头样式        
        HSSFFont font = wb.createFont();//创建字体对象
        font.setFontHeightInPoints((short) 24);
        HSSFCellStyle cellstyle=wb.createCellStyle();
        cellstyle.setBorderBottom(BorderStyle.THIN);//下边框
        cellstyle.setBorderLeft(BorderStyle.THIN);//左边框
        cellstyle.setBorderTop(BorderStyle.THIN);//上边框
        cellstyle.setBorderRight(BorderStyle.THIN);//右边框
        cellstyle.setAlignment(HorizontalAlignment.CENTER);//设置字体居中
        cellstyle.setFont(font); 
//        字段名样式
        HSSFFont font2 = wb.createFont();//创建字体对象
        font2.setFontHeightInPoints((short) 16);
        HSSFCellStyle cellstyle1=wb.createCellStyle();
        cellstyle1.setBorderBottom(BorderStyle.THIN);//下边框
        cellstyle1.setBorderLeft(BorderStyle.THIN);//左边框
        cellstyle1.setBorderTop(BorderStyle.THIN);//上边框
        cellstyle1.setBorderRight(BorderStyle.THIN);//右边框
        cellstyle1.setAlignment(HorizontalAlignment.CENTER);
        cellstyle1.setFont(font2); 
//        列表样式
        HSSFFont font1 = wb.createFont();//创建字体对象
        font1.setFontHeightInPoints((short) 12);
        HSSFCellStyle cellstyle2=wb.createCellStyle();
        cellstyle2.setBorderBottom(BorderStyle.THIN);//下边框
        cellstyle2.setBorderLeft(BorderStyle.THIN);//左边框
        cellstyle2.setBorderTop(BorderStyle.THIN);//上边框
        cellstyle2.setBorderRight(BorderStyle.THIN);//右边框
        cellstyle2.setFont(font1); 

        HSSFRow row = null;//创建行对象
        HSSFCell cell =null;//创建列对象

        CellRangeAddress cellRangeAddress =null;// new CellRangeAddress(0, 0, 0, 11);
        String yuanShi[] = new String[]{"序号","地区","部门","名称","编码","类型","创建时间"};
        // 合并单元格           前两个参数行     后两个列
        sheet.addMergedRegion(new CellRangeAddress(0,0,0, 6));//合并单元格
        row = sheet.createRow((short)0);//通过工作薄创建行对象
        cell = row.createCell((short)0);//通过行对象获得列对象
        cell.setCellValue("事项清单列表");//设置列的值
        cell.setCellStyle(cellstyle);//设置表格样式
        sheet.setDefaultRowHeight((short)30);
       //每次 
        row = sheet.createRow((short)1);//新建行对象
        for(int s=0;s<yuanShi.length;s++){
            cell = row.createCell((short)s);
            cell.setCellValue(yuanShi[s]);
            cell.setCellStyle(cellstyle1);
             sheet.setColumnWidth((short)0,(short)(15 * 300));
        }

        for(int j=0;j<object.size();j++){
            Object[] obj = object.get(j);
            row = sheet.createRow((short)j+2);

             cell = row.createCell((short)0);//创建列
             cell.setCellValue(j+1);//序号
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)0,(short)(15 * 150));

             cell = row.createCell((short)1);
             cell.setCellValue(obj[0].toString());//地区
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)1,(short)(15 * 300));

             cell = row.createCell((short)2);
             cell.setCellValue(obj[1].toString());//部门
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)2,(short)(15 * 300));

             cell = row.createCell((short)3);
             cell.setCellValue(obj[2].toString());//名称
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)3,(short)(20 * 300));

             cell = row.createCell((short)4);
             cell.setCellValue(obj[4].toString());//编码
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)4,(short)(15 * 300));

             cell = row.createCell((short)5);
             cell.setCellValue(obj[5].toString());//类型
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)5,(short)(15 * 300));

             cell = row.createCell((short)6);
             cell.setCellValue(obj[3].toString());//创建时间
             cell.setCellStyle(cellstyle2);
             sheet.setColumnWidth((short)6,(short)(30 * 300));

        }
        // 第五步，写入实体数据 实际应用中这些数据从数据库得到，  
        // 第六步，将文件存到指定位置  
        boolean t =false;
        try {  
            ServletOutputStream servletoutputstream = rep.getOutputStream();
            String fileName = "";
            if(req.getHeader("user-agent").indexOf("MSIE") != -1 || req.getHeader("user-agent").indexOf("rv:11") !=-1) {
                fileName = java.net.URLEncoder.encode("导出","utf-8") + ".xls"; 
            }else{
                fileName = new String("导出".getBytes("utf-8"),"iso-8859-1")+ ".xls"; 
            } 
            rep.setHeader("Content-disposition", "attachment; filename="+ fileName);
            rep.setContentType("application/vnd.ms-excel;charset=utf-8");
            wb.write(servletoutputstream); 
            servletoutputstream.flush();
            t =true;
            servletoutputstream.close();
        }  
        catch (Exception e) {  
            e.printStackTrace();  
        } 
        return t;