CSV文件導出詳細講解

一、准備jar  如下所以放入maven配置文件中

 

 二、controller層

 

 三、SERVICE層

 

 

 

 四、CsvUtil文件

/**
 * csv文件導入導出
 */
public class CsvUtil {

    /**
     * 獲取csv文件頭部信息
     * @param inputWay 模板文件路徑
     * @return
     * @throws IOException
     */
    public static List<String> getHeader(String inputWay) throws IOException {
        List<String> headers = new ArrayList<>();
        DataInputStream in = new DataInputStream(new FileInputStream(new File(inputWay)));
        BufferedReader br= new BufferedReader(new InputStreamReader(in,"GBK"));
        CSVParser parser = CSVFormat.EXCEL.parse(br);
        CSVRecord strings = parser.getRecords().get(0);
        int size = strings.size();
        for (int i = 0; i < size; i++) {
            headers.add(strings.get(i));
        }
        return headers;
    }

    /**
     * 生成csv文件
     * @param headers  csv文件頭部信息
     * @param outputWay  輸出地址
     * @param data   填充數據
     * @throws IOException
     */
    public static void generateCsvFile(List<String> headers, String outputWay, List<List<Object>> data) throws IOException {
        FileOutputStream fos = new FileOutputStream(outputWay);
        OutputStreamWriter osw = new OutputStreamWriter(fos, "GBK");
        String[] toBeStored = headers.toArray(new String[headers.size()]);
        CSVFormat csvFormat = CSVFormat.DEFAULT.withHeader(toBeStored);
        CSVPrinter csvPrinter = new CSVPrinter(osw, csvFormat);
        for (int i = 0; i < data.size(); i++) {//處理掉最后一個版本號
            List<Object> singleData = data.get(i);
            csvPrinter.printRecord(singleData);
        }
        csvPrinter.flush();
        csvPrinter.close();

    }

    /**
     * 寫出csv文件流
     * @param response
     * @param inputWay
     */
    public static void exportCsvFile(HttpServletResponse response,String inputWay,String fileName) throws IOException {
        OutputStream out = response.getOutputStream();
        byte[] b = new byte[1024];
        File fileLoad = new File(inputWay);
        response.reset();
        response.setContentType("application/csv");
        response.setHeader("content-disposition",  "attachment;filename="+ new String((fileName+".csv").getBytes()));
        long fileLength = fileLoad.length();
        String length1 = String.valueOf(fileLength);
        response.setHeader("Content_Length", length1);
        FileInputStream in = new FileInputStream(fileLoad);
        int n;
        while ((n = in.read(b)) != -1) {
            out.write(b, 0, n); //每次寫入out1024字節
        }
        in.close();
        out.close();
        // 刪除臨時文件
        fileLoad.delete();
    }
}

 

五、總結

 中間處理業務數據就可以了，放入到保存的list中，輸出格式一致就可以成功導出了！