DES加密解密工具类代码
这些都是项目中自己用到的，也算是自己做的一个小记录，作为一个菜鸟，大家有啥建议，请多多指教。
DES加密介绍
DES对称加密，对称加密，是一种比较传统的加密方式，其加密运算、解密运算使用的是同样的密钥，信息的发送者和信息的接收者在进行信息的传输与处理时，必须共同持有该密码（称为对称密码。
注意：DES加密和解密过程中，密钥长度都必须是8的倍数
下面是我在用到DES加密解密类里面，用到的秘钥（直接写死了，感觉不太好，大家可以自行改进，但长度必须是8的倍数）
public final static String key = "37d5aed075525d4fa0fe635231cba447";// 密钥
以下是正式代码===================
package org.aisino.fabric.utils;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
public class DESUtil {
private static final String DES_ALGORITHM = "DES";
/**
* DES加密
* @param plainData
* @param secretKey
* @return
* @throws Exception
*/
public static String encryption(String plainData, String secretKey) throws Exception{
Cipher cipher = null;
try {
cipher = Cipher.getInstance(DES_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, generateKey(secretKey));
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
}catch(InvalidKeyException e){
}
try {
// 为了防止解密时报javax.crypto.IllegalBlockSizeException: Input length must be multiple of 8 when decrypting with padded cipher异常，
// 不能把加密后的字节数组直接转换成字符串
byte[] buf = cipher.doFinal(plainData.getBytes());
return Base64Utils.encode(buf);
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
throw new Exception("IllegalBlockSizeException", e);
} catch (BadPaddingException e) {
e.printStackTrace();
throw new Exception("BadPaddingException", e);
}
}
/**
* DES解密
* @param secretData
* @param secretKey
* @return
* @throws Exception
*/
public static String decryption(String secretData, String secretKey) throws Exception{
Cipher cipher = null;
try {
cipher = Cipher.getInstance(DES_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, generateKey(secretKey));
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
throw new Exception("NoSuchAlgorithmException", e);
} catch (NoSuchPaddingException e) {
e.printStackTrace();
throw new Exception("NoSuchPaddingException", e);
}catch(InvalidKeyException e){
e.printStackTrace();
throw new Exception("InvalidKeyException", e);
}
try {
byte[] buf = cipher.doFinal(Base64Utils.decode(secretData.toCharArray()));
return new String(buf);
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
throw new Exception("IllegalBlockSizeException", e);
} catch (BadPaddingException e) {
e.printStackTrace();
throw new Exception("BadPaddingException", e);
}
}
/**
* 获得密钥
*
* @param secretKey
* @return
* @throws NoSuchAlgorithmException
*/
private static SecretKey generateKey(String secretKey) throws NoSuchAlgorithmException{
SecureRandom secureRandom = new SecureRandom(secretKey.getBytes());
// 为我们选择的DES算法生成一个KeyGenerator对象
KeyGenerator kg = null;
try {
kg = KeyGenerator.getInstance(DES_ALGORITHM);
} catch (NoSuchAlgorithmException e) {
}
kg.init(secureRandom);
//kg.init(56, secureRandom);
// 生成密钥
return kg.generateKey();
}
static class Base64Utils {
static private char[] alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=".toCharArray();
static private byte[] codes = new byte[256];
static {
for (int i = 0; i < 256; i++)
codes[i] = -1;
for (int i = 'A'; i <= 'Z'; i++)
codes[i] = (byte) (i - 'A');
for (int i = 'a'; i <= 'z'; i++)
codes[i] = (byte) (26 + i - 'a');
for (int i = '0'; i <= '9'; i++)
codes[i] = (byte) (52 + i - '0');
codes['+'] = 62;
codes['/'] = 63;
}
/**
* 将原始数据编码为base64编码
*/
static public String encode(byte[] data) {
char[] out = new char[((data.length + 2) / 3) * 4];
for (int i = 0, index = 0; i < data.length; i += 3, index += 4) {
boolean quad = false;
boolean trip = false;
int val = (0xFF & (int) data[i]);
val <<= 8;
if ((i + 1) < data.length) {
val |= (0xFF & (int) data[i + 1]);
trip = true;
}
val <<= 8;
if ((i + 2) < data.length) {
val |= (0xFF & (int) data[i + 2]);
quad = true;
}
out[index + 3] = alphabet[(quad ? (val & 0x3F) : 64)];
val >>= 6;
out[index + 2] = alphabet[(trip ? (val & 0x3F) : 64)];
val >>= 6;
out[index + 1] = alphabet[val & 0x3F];
val >>= 6;
out[index + 0] = alphabet[val & 0x3F];
}
return new String(out);
}
/**
* 将base64编码的数据解码成原始数据
*/
static public byte[] decode(char[] data) {
int len = ((data.length + 3) / 4) * 3;
if (data.length > 0 && data[data.length - 1] == '=')
--len;
if (data.length > 1 && data[data.length - 2] == '=')
--len;
byte[] out = new byte[len];
int shift = 0;
int accum = 0;
int index = 0;
for (int ix = 0; ix < data.length; ix++) {
int value = codes[data[ix] & 0xFF];
if (value >= 0) {
accum <<= 6;
shift += 6;
accum |= value;
if (shift >= 8) {
shift -= 8;
out[index++] = (byte) ((accum >> shift) & 0xff);
}
}
}
if (index != out.length)
throw new Error("miscalculated data length!");
return out;
}
}
}
最后附上一位优秀博主的文章：https://www.cnblogs.com/langtianya/p/3715975.html