大数据导出POI之SXSSFWorkbook

叁歲伎倆 2021-06-24 15:59 562阅读 0赞

[https://www.jianshu.com/p/df05c7fd6fa8][https_www.jianshu.com_p_df05c7fd6fa8]

POI还有[SXSSFWorkbook][]专门处理大数据

OutputStream os = null;  
    try {  
        HttpServletResponse response = super.getResponse();  
        response.setContentType("application/force-download"); // 设置下载类型  
        String filename ="risk_event.xlsx";  
        response.setHeader("Content-Disposition","attachment;filename=" + filename); // 设置文件的名称  
        os = response.getOutputStream(); // 输出流  
        SXSSFWorkbook wb = new SXSSFWorkbook(1000);//内存中保留 1000 条数据，以免内存溢出，其余写入 硬盘  
           //获得该工作区的第一个sheet     
        Sheet sheet1 = wb.createSheet("sheet1");   
           int excelRow = 0;  
           //标题行  
           Row titleRow = (Row) sheet1.createRow(excelRow++);  
        for (int i = 0; i < columnList.size(); i++) {  
            Cell cell = titleRow.createCell(i);    
                  cell.setCellValue(columnList.get(i));  
        }  
          
        for (int m = 0; m < cycleCount; m++) {  
            List<List<String>> eventStrList = this.convertPageModelStrList();  
            if (eventStrList!= null && eventStrList.size() > 0) {  
                for (int i = 0; i < eventStrList.size(); i++) {  
                    //明细行  
                    Row contentRow = (Row) sheet1.createRow(excelRow++);  
                    List<String> reParam = (List<String>) eventStrList.get(i);  
                    for (int j = 0; j < reParam.size(); j++) {  
                        Cell cell = contentRow.createCell(j);    
                        cell.setCellValue(reParam.get(j));  
                    }  
                }  
            }  
        }  
        wb.write(os);  
    } catch (Exception e) {  
        e.printStackTrace();  
    } finally {  
        try {  
            if (os != null) {  
                os.close();  
            }  
        } catch (IOException e) {  
            e.printStackTrace();  
        } // 关闭输出流  
    }

[https_www.jianshu.com_p_df05c7fd6fa8]: https://www.jianshu.com/p/df05c7fd6fa8
[SXSSFWorkbook]: https://link.jianshu.com/?t=http%3A%2F%2Fpoi.apache.org%2Fapidocs%2Forg%2Fapache%2Fpoi%2Fxssf%2Fstreaming%2FSXSSFWorkbook.html