近期,項目要求把服務器存儲的上傳文件,批量下載到本地.參考網上資料,實現了服務器文件打包成壓縮文件然后down到本地功能. 
具體代碼實現: 
1、在服務器端創(chuàng)建一個臨時zip格式文件 
2、用jdk自帶的API將服務器所有文件輸入到zip文件中 
3、將zip文件下載到本地，并刪除服務器端zip文件

@RequestMapping(value = "/downloadZip.do")
    public String downloadFiles(String tcLwIds, HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        List<File> files = new ArrayList<File>();
        File Allfile = new File(request.getSession().getServletContext().getRealPath("/") + "upload/");
        if (Allfile.exists()) {
            File[] fileArr = Allfile.listFiles();
            for (File file2 : fileArr) {
                files.add(file2);
            }
        }

        String fileName = UUID.randomUUID().toString() + ".zip";
        // 在服務器端創(chuàng)建打包下載的臨時文件
        String outFilePath = request.getSession().getServletContext().getRealPath("/") + "upload/";

        File fileZip = new File(outFilePath + fileName);
        // 文件輸出流
        FileOutputStream outStream = new FileOutputStream(fileZip);
        // 壓縮流
        ZipOutputStream toClient = new ZipOutputStream(outStream);
    //  toClient.setEncoding("gbk");
        zipFile(files, toClient);
        toClient.close();
        outStream.close();
        this.downloadFile(fileZip, response, true);
        return null;
    }
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

將服務器文件存到壓縮包中

public static void zipFile(List<File> files, ZipOutputStream outputStream) throws IOException, ServletException {
        try {
            int size = files.size();
            // 壓縮列表中的文件
            for (int i = 0; i < size; i++) {
                File file = (File) files.get(i);
                zipFile(file, outputStream);
            }
        } catch (IOException e) {
            throw e;
        }
    }
public static void zipFile(File inputFile, ZipOutputStream outputstream) throws IOException, ServletException {
        try {
            if (inputFile.exists()) {
                if (inputFile.isFile()) {
                    FileInputStream inStream = new FileInputStream(inputFile);
                    BufferedInputStream bInStream = new BufferedInputStream(inStream);
                    ZipEntry entry = new ZipEntry(inputFile.getName());
                    outputstream.putNextEntry(entry);

                    final int MAX_BYTE = 10 * 1024 * 1024; // 最大的流為10M
                    long streamTotal = 0; // 接受流的容量
                    int streamNum = 0; // 流需要分開的數量
                    int leaveByte = 0; // 文件剩下的字符數
                    byte[] inOutbyte; // byte數組接受文件的數據

                    streamTotal = bInStream.available(); // 通過available方法取得流的最大字符數
                    streamNum = (int) Math.floor(streamTotal / MAX_BYTE); // 取得流文件需要分開的數量
                    leaveByte = (int) streamTotal % MAX_BYTE; // 分開文件之后,剩余的數量

                    if (streamNum > 0) {
                        for (int j = 0; j < streamNum; ++j) {
                            inOutbyte = new byte[MAX_BYTE];
                            // 讀入流,保存在byte數組
                            bInStream.read(inOutbyte, 0, MAX_BYTE);
                            outputstream.write(inOutbyte, 0, MAX_BYTE); // 寫出流
                        }
                    }
                    // 寫出剩下的流數據
                    inOutbyte = new byte[leaveByte];
                    bInStream.read(inOutbyte, 0, leaveByte);
                    outputstream.write(inOutbyte);
                    outputstream.closeEntry(); // Closes the current ZIP entry
                    // and positions the stream for
                    // writing the next entry
                    bInStream.close(); // 關閉
                    inStream.close();
                }
            } else {
                throw new ServletException("文件不存在！");
            }
        } catch (IOException e) {
            throw e;
        }
    }
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56

下載文件

 public void downloadFile(File file,HttpServletResponse response,boolean isDelete) {
          try {
              // 以流的形式下載文件。
              BufferedInputStream fis = new BufferedInputStream(new FileInputStream(file.getPath()));
              byte[] buffer = new byte[fis.available()];
              fis.read(buffer);
              fis.close();
              // 清空response
              response.reset();
              OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
              response.setContentType("application/octet-stream");
              response.setHeader("Content-Disposition", "attachment;filename=" + new String(file.getName().getBytes("UTF-8"),"ISO-8859-1"));
              toClient.write(buffer);
              toClient.flush();
              toClient.close();
              if(isDelete)
              {
                  file.delete();        //是否將生成的服務器端文件刪除
              }
           } 
           catch (IOException ex) {
              ex.printStackTrace();
          }
      } 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

單個文件的下載

@RequestMapping(value="/singleDownload.do")
    public String singleDownload(String fileName, HttpServletRequest request,
            HttpServletResponse response)throws Exception{
        response.setCharacterEncoding("utf-8");
        response.setContentType("multipart/form-data");
        response.setHeader("Content-Disposition", "attachment;fileName="+ fileName);
        String realPath = request.getSession().getServletContext().getRealPath("/");
        String path = realPath+"upload/";
        File file = new File(path+ File.separator + fileName);
        downloadFile(file, response, false);
        return null;
    }
1
2
3
4
5
6
7
8
9
10
11
12