Md5\Base64\Des 常用加密算法

常用的几种加解密方式备份：

 

1、MD5方式：

import java.security.MessageDigest;

 

String s= "test";

 

MessageDigest md5 = MessageDigest.getInstance("MD5");

byte[] byteArray = md5.digest(s.getBytes("UTF-8"));

 

 

 

 

2、Base64方式：

import org.apache.commons.codec.binary.Base64;

 

String s="test";

Base64.decodeBase64(s.getBytes("UTF-8"));

 

 

 

byte[] encodeBytes = Base64.encodeBase64(s.getBytes("UTF-8"), true);

String encodeString  =  new String(encodeBytes).trim();

 

 

 

3、Des方式：

import javax.crypto.Cipher;

import javax.crypto.KeyGenerator;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

import javax.crypto.spec.DESedeKeySpec;

import javax.crypto.spec.IvParameterSpec;

 

private static final String DEFAULT_ENCRYPT_MODE = "DES/ECB/PKCS5Padding";

private static final String DEFAULT_KEY_ALGORITHM = "DES";

private static final String DESEDE_KEY_ALGORITHM = "DESede";

 

 

public static byte[] DES(byte[] bytes, String algorithm, int iMode, byte[] key, byte[] iv) {

if (StringUtils.isEmpty(algorithm)) {

algorithm = DEFAULT_ENCRYPT_MODE;

}

if (iMode != Cipher.ENCRYPT_MODE && iMode != Cipher.DECRYPT_MODE) {

throw new IllegalArgumentException("iMode只能为1或2");

}

 

try {

DESKeySpec desKeySpec = new DESKeySpec(key);

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DEFAULT_KEY_ALGORITHM);

SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

 

Cipher cipher = Cipher.getInstance(algorithm);

if (iv != null) {

IvParameterSpec ivps = new IvParameterSpec(iv);

cipher.init(iMode, secretKey, ivps);

} else {

cipher.init(iMode, secretKey);

}

return cipher.doFinal(bytes);

} catch (Exception ex) {

logger.error("", ex);

}

return null;

}

 

//加解密转换用DESede

 

public static byte[] DESede(byte[] bytes, String algorithm, int iMode, byte[] key, byte[] iv) {

if (StringUtils.isEmpty(algorithm)) {

algorithm = DEFAULT_ENCRYPT_MODE;

}

if (iMode != Cipher.ENCRYPT_MODE && iMode != Cipher.DECRYPT_MODE) {

throw new IllegalArgumentException("iMode只能为1或2");

}

 

try {

DESedeKeySpec desKeySpec = new DESedeKeySpec(key);

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DESEDE_KEY_ALGORITHM);

SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

 

Cipher cipher = Cipher.getInstance(algorithm);

if (iv != null) {

IvParameterSpec ivps = new IvParameterSpec(iv);

cipher.init(iMode, secretKey, ivps);

} else {

cipher.init(iMode, secretKey);

}

return cipher.doFinal(bytes);

} catch (Exception ex) {

logger.error("", ex);

}

return null;

}

 

public static byte[] DESedeWithPKCS7Padding(byte[] bytes, String algorithm, int iMode,

byte[] key, byte[] iv) {

// DESede/ECB/PKCS5Padding

if (StringUtils.isEmpty(algorithm)) {

algorithm = DEFAULT_ENCRYPT_MODE;

}

if (iMode != Cipher.ENCRYPT_MODE && iMode != Cipher.DECRYPT_MODE) {

throw new IllegalArgumentException("iMode只能为1或2");

}

 

try {

DESedeKeySpec desKeySpec = new DESedeKeySpec(key);

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DESEDE_KEY_ALGORITHM);

SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

 

Cipher cipher = Cipher.getInstance(algorithm, "BC");

if (iv != null) {

IvParameterSpec ivps = new IvParameterSpec(iv);

cipher.init(iMode, secretKey, ivps);

} else {

cipher.init(iMode, secretKey);

}

return cipher.doFinal(bytes);

} catch (Exception ex) {

ex.printStackTrace();

logger.error("", ex);

}

return null;

}

 

 

 

4、Hex与byte[]转换：

 

 

/**

* 将字节数组转换为16进制字符串表示

* 

* @param bytes

*            待转换的字节数组

* @return 16进制表示的字符串

*/

public static String bytes2Hex(byte[] bytes) {

StringBuilder sb = new StringBuilder();

String hex = null;

for (int i = 0; i < bytes.length; i++) {

hex = Integer.toHexString(bytes[i] & 0xFF);

if (hex.length() == 1) {

sb.append("0");

}

sb.append(hex);

}

return sb.toString();

}

 

/**

* 将16进制字符串转换为字节数组

* 

* @param hexstr

* @return

*/

public static byte[] hex2Bytes(String hexstr) {

byte[] b = hexstr.getBytes();

int length = b.length;

if ((length % 2) != 0) {

throw new IllegalArgumentException("字符串对应字节数必须是偶数");

}

byte[] b2 = new byte[b.length / 2];

for (int n = 0; n < b.length; n += 2) {

String item = new String(b, n, 2);

b2[n / 2] = (byte) Integer.parseInt(item, 16);

}

return b2;

}