Java 上传和下载文件（附加密和解密）

import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientHandlerException;
import com.sun.jersey.api.client.UniformInterfaceException;
import com.sun.jersey.api.client.WebResource;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.UUID;

public class FileUtils {

    // 加密/解密文件的密钥
    public static final int CRYPTO_SECRET_KEY = 0x99;

    public static int FILE_DATA = 0;

    
    public static void cryptoFile(File srcFile, File encFile) throws Exception {

 InputStream inputStream = new FileInputStream(srcFile);
 OutputStream outputStream = new FileOutputStream(encFile);
 while ((FILE_DATA = inputStream.read()) > -1) {
     outputStream.write(FILE_DATA ^ CRYPTO_SECRET_KEY);
 }
 inputStream.close();
 outputStream.flush();
 outputStream.close();
    }

    
    public static File multipartFileToFile(MultipartFile multipartFile, String tempFilePath) {

 File file = new File(tempFilePath);
 // 获取文件原名
 String originalFilename = multipartFile.getOriginalFilename();
 // 获取文件后缀
 String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
 if (!file.exists()) {
     file.mkdirs();
 }
 // 创建临时文件
 File tempFile = new File(tempFilePath + "\" + UUID.randomUUID().toString().replaceAll("-", "") + suffix);
 try {
     if (!tempFile.exists()) {
  // 写入临时文件
  multipartFile.transferTo(tempFile);
     }
 } catch (IOException e) {
     e.printStackTrace();
 }
 return tempFile;
    }

    
    public static String uploadByJersey(String fileServerPath, String folderPath, File uploadFile, boolean isCrypto) {

 String suffix = uploadFile.getName().substring(uploadFile.getName().lastIndexOf("."));
 String randomFileName = UUID.randomUUID().toString().replaceAll("-", "") + suffix;
 String fullPath = fileServerPath + folderPath + "/" + randomFileName;
 try {
     if (isCrypto) {
  // 创建加密文件
  File cryptoFile = new File(uploadFile.getPath().substring(0, uploadFile.getPath().lastIndexOf(".")) + "crypto" + uploadFile.getPath().substring(uploadFile.getPath().lastIndexOf(".")));
  // 执行加密
  cryptoFile(uploadFile, cryptoFile);
  // 保存加密后的文件
  uploadFile = cryptoFile;
     }
     // 创建 Jersey 服务器
     Client client = Client.create();
     WebResource wr = client.resource(fullPath);
     // 上传文件
     wr.put(String.class, fileToByte(uploadFile));
 } catch (Exception e) {
     e.printStackTrace();
 }
 return fullPath;
    }

    
    public static File downloadByURL(String url, String filePath, String fileName, boolean isCrypto) {

 File file = new File(filePath);
 if (!file.exists()) {
     file.mkdirs();
 }
 FileOutputStream fileOut;
 HttpURLConnection httpURLConnection;
 InputStream inputStream;
 try {
     URL httpUrl = new URL(url);
     httpURLConnection = (HttpURLConnection) httpUrl.openConnection();
     httpURLConnection.setDoInput(true);
     httpURLConnection.setDoOutput(true);
     httpURLConnection.setUseCaches(false);
     httpURLConnection.connect();
     inputStream = httpURLConnection.getInputStream();
     BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
     if (!filePath.endsWith("\")) {
  filePath += "\";
     }
     file = new File(filePath + fileName);
     fileOut = new FileOutputStream(file);
     BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(fileOut);
     byte[] bytes = new byte[4096];
     int length = bufferedInputStream.read(bytes);
     //保存文件
     while (length != -1) {
  bufferedOutputStream.write(bytes, 0, length);
  length = bufferedInputStream.read(bytes);
     }
     bufferedOutputStream.close();
     bufferedInputStream.close();
     httpURLConnection.disconnect();
 } catch (Exception e) {
     e.printStackTrace();
 }
 if (isCrypto) {
     try {
  // 创建解密文件
  File cryptoFile = new File(((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest().getServletContext().getRealPath("/") +  "\temp\" + UUID.randomUUID().toString().replaceAll("-", "") + file.getName().substring(file.getName().lastIndexOf(".")));
  // 执行解密
  cryptoFile(file, cryptoFile);
  // 删除下载的原文件
  file.delete();
  // 保存解密后的文件
  file = cryptoFile;
     } catch (Exception e) {
  e.printStackTrace();
     }
 }
 return file;
    }

    
    public static boolean deleteByJersey(String url) {

 try {
     Client client = new Client();
     WebResource webResource = client.resource(url);
     webResource.delete();
     return true;
 } catch (UniformInterfaceException e) {
     e.printStackTrace();
 } catch (ClientHandlerException e) {
     e.printStackTrace();
 }
 return false;
    }

    
    public static byte[] fileToByte(File file) {

 byte[] buffer = null;
 try {
     FileInputStream fileInputStream = new FileInputStream(file);
     ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
     byte[] bytes = new byte[1024];
     int n;
     while ((n = fileInputStream.read(bytes)) != -1) {
  byteArrayOutputStream.write(bytes, 0, n);
     }
     fileInputStream.close();
     byteArrayOutputStream.close();
     buffer = byteArrayOutputStream.toByteArray();
 } catch (FileNotFoundException e) {
     e.printStackTrace();
 } catch (IOException e) {
     e.printStackTrace();
 }
 return buffer;
    }
}

@Test
public String upload(MultipartFile multipartFile, boolean isCrypto) {

    HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
    // 生成临时文件
    File tempFile = FileUtil.multipartFileToFile(multipartFile, request.getServletContext().getRealPath("/") + "\static\temp");
    // 上传文件并返回文件路径
    String uploadFilePath = FileUtil.uploadByJersey("http://localhost:8080", "/upload", tempFile, isCrypto);
    if (uploadFilePath != null) {
 return "上传成功";
    }
    else {
 return "上传失败";
    }
}