Java Cipher 解密中的奇怪字符
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【中文标题】Java Cipher 解密中的奇怪字符【英文标题】：Java Cipher Strange chars in decryption 【发布时间】：2016-06-23 10:15:20 【问题描述】：我的程序有一个奇怪的问题，我想加密一些字符串然后解密它们；我做了一个试用类来测试加密和解密的功能。加密工作正常，但是当我尝试解密时，只有有时，我在字符串中间有奇怪的字符。 这是我的代码：
public class Prova
public static void main(String[] args)
String s = "with the lights out is less dangerous here we are now entertain us";
s = cripta(s);
System.out.println(s);
s = decripta(s);
System.out.println(s);
public static String cripta(String s)
System.out.println("lunghezza stringa:"+s.length());
byte[] input = s.getBytes();
byte[] output;
byte[] keyBytes = hexStringToByteArray("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
byte[] ivBytes = hexStringToByteArray("AAAAAAAAAAAAAAAA");
String out = "";
SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede" );
IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
try
Cipher cp = Cipher.getInstance("DESede/ECB/PKCS5Padding");
cp.init(Cipher.ENCRYPT_MODE, key);
byte[] criptati = new byte[cp.getOutputSize(input.length)];
int enc_len = cp.update(input, 0, input.length, criptati, 0);
enc_len += cp.doFinal(criptati, enc_len);
out = new String(criptati);
catch (NoSuchAlgorithmException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (NoSuchPaddingException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (InvalidKeyException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (ShortBufferException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (IllegalBlockSizeException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (BadPaddingException e)
// TODO Auto-generated catch block
e.printStackTrace();
return out;
public static String decripta(String s)
byte[] input = s.getBytes();
byte[] output;
byte[] keyBytes = hexStringToByteArray("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
byte[] ivBytes = hexStringToByteArray("AAAAAAAAAAAAAAAA");
String out = "";
try
SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede");
IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
Cipher cp = Cipher.getInstance("DESede/ECB/NoPadding");
cp.init(Cipher.DECRYPT_MODE, key);
byte[] decrypt = new byte[cp.getOutputSize(input.length)];
int dec_len = cp.update(input, 0, input.length, decrypt, 0);
System.out.println(dec_len);
dec_len += cp.doFinal(decrypt, dec_len );
System.out.println(dec_len);
out = new String(decrypt);
catch (NoSuchAlgorithmException | NoSuchPaddingException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (InvalidKeyException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (ShortBufferException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (IllegalBlockSizeException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (BadPaddingException e)
// TODO Auto-generated catch block
e.printStackTrace();
return out;
private static byte[] hexStringToByteArray(String s)
// TODO Auto-generated method stub
int len = s.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2)
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
return data;
我收到的输出是“熄灯后的 dangÝâ¥8,–xÖÆZŽÏö=æe 现在招待我们”
【问题讨论】：
String 不是二进制数据的容器。
【参考方案1】：
问题是加密字节可能包含一些值，这些值在简单地转换为字符串时会导致奇怪的行为。所以你应该像这样使用base64编码：
在密码中：
out = new String(Base64.getEncoder().encode(criptati));
简述：
byte[] input = Base64.getDecoder().decode(s.getBytes());
顺便问一下：你为什么用cp.update()？为什么不只是 cp.doFinal() 那样：
Cipher cp = Cipher.getInstance("DESede/ECB/PKCS5Padding");
cp.init(Cipher.ENCRYPT_MODE, key);
byte[] criptati = cp.doFinal(input);
out = new String(Base64.getEncoder().encode(criptati));
decript 也一样？
编辑
删除所有杂乱（TODO-cmets、未使用的代码等）的工作示例：
public static void main(String[] args)
String s = "with the lights out is less dangerous here we are now entertain us";
s = cripta(s);
System.out.println(s);
s = decripta(s);
System.out.println(s);
public static String cripta(String s)
System.out.println("lunghezza stringa:" + s.length());
byte[] input = s.getBytes();
byte[] keyBytes = hexStringToByteArray("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
String out = "";
SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede");
try
Cipher cp = Cipher.getInstance("DESede/ECB/PKCS5Padding");
cp.init(Cipher.ENCRYPT_MODE, key);
byte[] criptati = cp.doFinal(input);
out = new String(Base64.getEncoder().encode(criptati));
catch (NoSuchAlgorithmException e)
e.printStackTrace();
catch (NoSuchPaddingException e)
e.printStackTrace();
catch (InvalidKeyException e)
e.printStackTrace();
catch (IllegalBlockSizeException e)
e.printStackTrace();
catch (BadPaddingException e)
e.printStackTrace();
return out;
public static String decripta(String s)
byte[] input = Base64.getDecoder().decode(s.getBytes());
byte[] keyBytes = hexStringToByteArray("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
String out = "";
try
SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede");
Cipher cp = Cipher.getInstance("DESede/ECB/NoPadding");
cp.init(Cipher.DECRYPT_MODE, key);
byte[] decrypt = cp.doFinal(input);
out = new String(decrypt);
catch (NoSuchAlgorithmException | NoSuchPaddingException e)
e.printStackTrace();
catch (InvalidKeyException e)
e.printStackTrace();
catch (IllegalBlockSizeException e)
e.printStackTrace();
catch (BadPaddingException e)
e.printStackTrace();
return out;
【讨论】：
现在我收到此错误：线程“main”java.lang.IllegalArgumentException 中的异常：非法 base64 字符 20 它工作，我使用你的解决方案出错了，现在它似乎工作了，非常感谢你的帮助！以上是关于Java Cipher 解密中的奇怪字符的主要内容，如果未能解决你的问题，请参考以下文章