使用Base64加密解密文件

import java.io.ByteArrayInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
* Base64工具类
*
*/
public class Base64Util {

public static String fileToBase64(String filepath, String filename) throws IOException {
String fileName = filepath + filename; // 源文件
String strBase64 = null;
InputStream in = null;
try {
in = new FileInputStream(fileName);
// in.available()返回文件的字节长度
byte[] bytes = new byte[in.available()];
// 将文件中的内容读入到数组中
in.read(bytes);
// strBase64 = new BASE64Encoder().encode(bytes); // 将字节流数组转换为字符串
strBase64 = encode(bytes); // 将字节流数组转换为字符串
} catch (FileNotFoundException fe) {
fe.printStackTrace();
} catch (IOException ioe) {
ioe.printStackTrace();
}finally{
if(in!=null)
in.close();
}
return strBase64;
}

public static String fileToBase64(String filepathame) throws IOException {
String fileName = filepathame; // 源文件
String strBase64 = null;
try {
InputStream in = new FileInputStream(fileName);
// in.available()返回文件的字节长度
byte[] bytes = new byte[in.available()];
// 将文件中的内容读入到数组中
in.read(bytes);
// strBase64 = new BASE64Encoder().encode(bytes); // 将字节流数组转换为字符串
strBase64 = encode(bytes); // 将字节流数组转换为字符串
in.close();
} catch (FileNotFoundException fe) {
fe.printStackTrace();
} catch (IOException ioe) {
ioe.printStackTrace();
}
return strBase64;
}

public static String base64ToFile(String strBase64, String filepath, String filename) throws IOException {
String string = strBase64;
FileUtils.createNewFileDirectory(filepath);
String fileName = filepath + filename;// 生成的新文件
ByteArrayInputStream in = null;
FileOutputStream out = null;
try {
// 解码，然后将字节转换为文件
// byte[] bytes = new BASE64Decoder().decodeBuffer(string);
// byte[] bytes = decode(string.trim().replaceAll(" ", ""));
byte[] bytes = decode(string.trim());
// 将字符串转换为byte数组
in = new ByteArrayInputStream(bytes);
byte[] buffer = new byte[1024];
out = new FileOutputStream(fileName);
int bytesum = 0;
int byteread = 0;
while ((byteread = in.read(buffer)) != -1) {
bytesum += byteread;
out.write(buffer, 0, byteread); // 文件写操作
}
} catch (IOException ioe) {
ioe.printStackTrace();
}finally{
if(out!=null)
out.close();
if(in!=null)
in.close();
}
return fileName;
}

/
9a61
**
* 编码
*
* @param bstr
* @return String
*/
public static String encode(byte[] bstr) {
return new BASE64Encoder().encode(bstr);
}

/**
* 解码
*
* @param str
* @return string
*/
public static byte[] decode(String str) {
byte[] bt = null;
try {
BASE64Decoder decoder = new BASE64Decoder();
bt = decoder.decodeBuffer(str);
} catch (IOException e) {
e.printStackTrace();
}
return bt;
}

public static void main(String[] args) {
try {
//将文件流化
System.out.println(fileToBase64("E:\\", "2.pdf"));
//将流化文件重新生成文件
base64ToFile(fileToBase64("E:\\", "2.pdf"), "E:\\", "zhu.pdf");
} catch (IOException e1) {
// TODO Auto-generated catch block
System.out.println("error");
e1.printStackTrace();
}
}
}