关于springmvc下服务器文件打包成zip格式下载功能
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近期,项目要求把服务器存储的上传文件,批量下载到本地.参考网上资料,实现了服务器文件打包成压缩文件然后down到本地功能.
具体代码实现:
1、在服务器端创建一个临时zip格式文件
2、用jdk自带的API将服务器所有文件输入到zip文件中
3、将zip文件下载到本地,并删除服务器端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";
// 在服务器端创建打包下载的临时文件
String outFilePath = request.getSession().getServletContext().getRealPath("/") + "upload/";
File fileZip = new File(outFilePath + fileName);
// 文件输出流
FileOutputStream outStream = new FileOutputStream(fileZip);
// 压缩流
ZipOutputStream toClient = new ZipOutputStream(outStream);
// toClient.setEncoding("gbk");
zipFile(files, toClient);
toClient.close();
outStream.close();
this.downloadFile(fileZip, response, true);
return null;
}
将服务器文件存到压缩包中
public static void zipFile(List<File> files, ZipOutputStream outputStream) throws IOException, ServletException {
try {
int size = files.size();
// 压缩列表中的文件
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; // 最大的流为10M
long streamTotal = 0; // 接受流的容量
int streamNum = 0; // 流需要分开的数量
int leaveByte = 0; // 文件剩下的字符数
byte[] inOutbyte; // byte数组接受文件的数据
streamTotal = bInStream.available(); // 通过available方法取得流的最大字符数
streamNum = (int) Math.floor(streamTotal / MAX_BYTE); // 取得流文件需要分开的数量
leaveByte = (int) streamTotal % MAX_BYTE; // 分开文件之后,剩余的数量
if (streamNum > 0) {
for (int j = 0; j < streamNum; ++j) {
inOutbyte = new byte[MAX_BYTE];
// 读入流,保存在byte数组
bInStream.read(inOutbyte, 0, MAX_BYTE);
outputstream.write(inOutbyte, 0, MAX_BYTE); // 写出流
}
}
// 写出剩下的流数据
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(); // 关闭
inStream.close();
}
} else {
throw new ServletException("文件不存在!");
}
} catch (IOException e) {
throw e;
}
}
下载文件
public void downloadFile(File file,HttpServletResponse response,boolean isDelete) {
try {
// 以流的形式下载文件。
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(); //是否将生成的服务器端文件删除
}
}
catch (IOException ex) {
ex.printStackTrace();
}
}
单个文件的下载
@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;
}