Java 上传和下载文件（附加密和解密）

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使用

Jersey

HTTP

引入依赖

在

pom.xml

Jersey

<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-client</artifactId>
<version>1.18.1</version>
</dependency>

创建工具类

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;

/**
* 加密/解密 文件
* @param srcFile 原文件
* @param encFile 加密/解密后的文件
* @throws Exception
*/
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();
}

/**
* MultipartFile 生成临时文件
* @param multipartFile
* @param tempFilePath 临时文件路径
* @return File 临时文件
*/
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;
}

/**
* 上传文件
* @param fileServerPath    文件服务器地址
* @param folderPath    存放的文件夹路径（比如存放在文件服务器的 upload 文件夹下，即 ”/upload“）
* @param uploadFile    需要上传的文件
* @param isCrypto  是否加密
* @return String   文件上传后的全路径
*/
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;
}

/**
* 下载文件
* @param url   文件路径
* @param filePath  文件保存路径
* @param fileName  文件名称（包含文件后缀）
* @param isCrypto  是否解密
* @return File
*/
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;
}

/**
* 删除文件服务器上的文件
* @param url 文件路径
* @return boolean
*/
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;
}

/**
* File转Bytes
* @param file
* @return byte[]
*/
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;
}
}

测试上传

/**
* @param multipartFile 上传文件
* @param isCrypto 是否加密文件
* @return
*/
@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";
}
}