poi 万级数据下载（excel文件导出）

org.apache.poi中的jar包准备

1. poi-ooxml 3.14
2. poi-ooxml-schemas 3.14(可以不用)
3. poi 3.14

impot org.apache.poi.ss.usermodel.Row;

impot org.apache.poi.ss.usermodel.Cell;

impot org.apache.poi.ss.usermodel.Sheet;

impot org.apache.poi.xssf.streaming.SXSSFWorkbook;

public static void download(String file, HttpServletRequest request,
            HttpServletResponse response) {
        try {
            File tempFile = new File(file.trim());
            String fileName = tempFile.getName();
            InputStream is = new FileInputStream(file);
            response.reset(); // 必要地清除response中的缓存信息
         

            //文件命名
            response.setHeader("Content-Disposition", "attachment; filename="
                    new String ("文件名".getByte(),"ISO8859-1"+dateFormate(dataFile)+".xlsx")

            / /+java.net.URLEncoder.encode(fileName, "UTF-8"));

            //下载xlsx文件

            response.setContType("applaication/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=utf-8")

            ServletOutputStream out = response.getOutputStream();

             byte[] content = new byte[1024]; int length = 0; 

            while((length = is.read(content)) != -1) {//请留意read里面的参数 

                out.write(content, 0, length); } 

                out.flush(); 

                out.close();
　　　　　　　    is.close(); } 

            catch (Exception e) { e.printStackTrace(); } }

（主要还是流的应用，要去了解输入输出流才行，具体代码参见其它只提供思路和包路径，还要，要相信自己，

先写出下载再做更改很快）