POI導入データを使ってExcelデータ量が多すぎるとエラー解決案が出ます。

エクスポートエクセルは4000行のエラーを超えてはいけません。   POI操作エクセルでは、導出したデータが大きくない場合は問題ないが、データが多い場合や多い場合は、
以下のエラーを報告します。cell styleが多すぎるので、cell tyleをサイクル外に置いてエラーを報告します。
java.lang.IllagalStation Exception：The maximnumber of cell style was exceded.You can define up to 4000 style in a.xls workbook        at org.apaache.poi.hssf.usermodel.HSSFWork book.createCelStele(HSSFWork book.java:1162)
エラーの例

for (int i = 0; i < 10000; i++) {  
    Row row = sheet.createRow(i);   
    Cell cell = row.createCell((short) 0);   
    CellStyle style = workbook.createCellStyle();  
    Font font = workbook.createFont();   
    font.setBoldweight(Font.BOLDWEIGHT_BOLD);   
    style.setFont(font);   
    cell.setCellStyle(style);  
}  

修正後の正しいコード

CellStyle style = workbook.createCellStyle();  
Font font = workbook.createFont();  
font.setBoldweight(Font.BOLDWEIGHT_BOLD);  
style.setFont(font);  
for (int i = 0; i < 10000; i++) {   
    Row row = sheet.createRow(i);   
    Cell cell = row.createCell((short) 0);   
    cell.setCellStyle(style);  
} 

以下はエクセルのコアコードを生成します。

public static void export( ExcelBean excelBean, HttpServletResponse response) throws IOException {
        String filename = excelBean.getName();
        filename = new String(filename.replaceAll("\\s|;", "").getBytes("gbk"), "ISO8859-1");

        response.setContentType("application/octet-stream;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        response.setContentType("application/vnd.ms-excel");
        response.setHeader("Content-disposition", "attachment;filename=" + filename);
        OutputStream outputStream = response.getOutputStream();
        createExcel(excelBean, outputStream);
        outputStream.flush();
        outputStream.close(); 
    }

public static void createExcel(ExcelBean excelBean, OutputStream outputStream) throws IOException{
        //        
        HSSFWorkbook wb = new HSSFWorkbook();
        //       
        HSSFSheet sheet = wb.createSheet(excelBean.getSheetName());
        HSSFRow row0 = sheet.createRow(0);

        int descIndexBegin = 9;
        // int descIndexEnd = 12;
        HSSFRow row9 = sheet.createRow(descIndexBegin);


        HSSFRow row = sheet.createRow(1);
        row.setHeightInPoints(25.0f);//   ：25  

        //    
        HSSFCellStyle style = wb.createCellStyle();
        HSSFCellStyle descStyle = wb.createCellStyle();
        //         
        setAlignCenter(style);
        //        
        setTitleStyle(wb,style);

        if(excelBean.isHeadBold()){
            HSSFFont headfont = wb.createFont();
            headfont.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
            style.setFont(headfont);
        }

        HSSFCell cell;
        ExcelTitle[] titles = excelBean.getTitles();

        //==========      (        )==========
        if(titles.length>=2){
            sheet.addMergedRegion(new CellRangeAddress(0,0,0,titles.length-1));//   ，   ，   ，   
        }

        cell = row0.createCell(0);
        String topTitle = excelBean.getName();
        String titleName = topTitle.substring(0,topTitle.lastIndexOf("."));
        cell.setCellValue(titleName);//     
        cell.setCellStyle(style);
        setTopTitleStyle(wb,cell,titleName);
        //==========      (        )==========

        //====================    ==========begin==========
        String desc = excelBean.getDescription();
        if(StringUtils.isNoneBlank(desc)){
            if(titles.length>=2){
                sheet.addMergedRegion(new CellRangeAddress(descIndexBegin,descIndexBegin,0,titles.length-1));//firstRow, lastRow, firstCol, lastCol
            }
            HSSFCell descCell = row9.createCell(0);
            descCell.setCellValue("**  ："+desc+"\r
                ");//     
//            setAlignLeft(style);
            setAlignLeftAndTop(descCell,descStyle);//            
        }
        //====================    ==========end==========

        //====================      ====================
        for(int i=0; i < titles.length; i++){
            ExcelTitle title = titles[i];
            cell= row.createCell(i);

            //       '  、    '，      
            String titleValue = title.getValue();
            int beginIndex = titleValue.indexOf("(");
            int endIndex = titleValue.indexOf(")");
            String subTitle = titleValue.substring(beginIndex,endIndex);

            if(subTitle.contains("  ") || subTitle.contains("    ")){

                HSSFRichTextString ts= new HSSFRichTextString(titleValue);

                HSSFFont font = wb.createFont();
                font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
                font.setColor(HSSFColor.RED.index);
                font.setFontHeightInPoints((short) 14);//       

                HSSFFont font2 = wb.createFont();
                font2.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
                font2.setFontHeightInPoints((short) 14);//       

                ts.applyFont(0,beginIndex,font2);//    
                ts.applyFont(beginIndex,endIndex+1,font);//    
                cell.setCellValue(ts);
            }else{
                cell.setCellValue(titleValue);
            }

            cell.setCellStyle(style);

            int columnWidth = title.getWidth() > 0 ? title.getWidth() : excelBean.getColumnWidth();
            sheet.setColumnWidth(i, getColWidth(columnWidth));
        }

        //====================       ====================

        //====================  tips:example====================
        int rowIndex = 2;
        int rowHeight = excelBean.getRowHeight();
        HSSFPatriarch patriarch = sheet.createDrawingPatriarch();

        HSSFCellStyle cellStyle = wb.createCellStyle();
        for(String[] data : excelBean.getDataList()){
            row = sheet.createRow(rowIndex ++ );
            if(rowHeight > 0){
                row.setHeight((short) getRowHeight(rowHeight));
            }
            else{
                rowHeight = 18;
            }
            for(int j=0; j 0 ? titles[j].getWidth() : excelBean.getColumnWidth();
                        insertImage(wb, patriarch, value, rowHeight, columnWidth, (short)(j), rowIndex);
                    }
                    else{
                        setLink(wb, cell, value);
                    }
                }else{*/
                    cell.setCellValue(value);

                    cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
                    cell.setCellStyle(cellStyle);
               /* }*/

            }
        }

        for (String[] tipsList : excelBean.getTipsList()) {
            row = sheet.getRow(1);//        
            for(int j=0; j