以下两个类可以很方便的完成字符串的加密和解密
加密 CryptHelper encrypt(password)
解密 CrypHelper decrypt(password)
代码如下
CryptUtils java
[java]
package gdie lab crypt;
import java io IOException;
import javax crypto Cipher;
import javax crypto KeyGenerator;
import javax crypto SecretKey;
import apache xerces internal impl dv util Base ;
public class CryptUtils {
private static String Algorithm = DES ;
private static byte[] DEFAULT_KEY=new byte[] { };
private static String VALUE_ENCODING= UTF ;
/**
* 生成密钥
*
* @return byte[] 返回生成的密钥
* @throws exception
* 扔出异常
*/
public static byte[] getSecretKey() throws Exception {
KeyGenerator keygen = KeyGenerator getInstance(Algorithm)
SecretKey deskey = keygen generateKey()
// if (debug ) System out println ( 生成密钥 +byte hex (deskey getEncoded
// ()))
return deskey getEncoded()
}
/**
* 将指定的数据根据提供的密钥进行加密
*
* @param input
* 需要加密的数据
* @param key
* 密钥
* @return byte[] 加密后的数据
* @throws Exception
*/
public static byte[] encryptData(byte[] input byte[] key) throws Exception {
SecretKey deskey = new javax crypto spec SecretKeySpec(key Algorithm)
// if (debug )
// {
// System out println ( 加密前的二进串 +byte hex (input ))
// System out println ( 加密前的字符串 +new String (input ))
//
// }
Cipher c = Cipher getInstance(Algorithm)
c init(Cipher ENCRYPT_MODE deskey)
byte[] cipherByte = c doFinal(input)
// if (debug ) System out println ( 加密后的二进串 +byte hex (cipherByte ))
return cipherByte;
}
public static byte[] encryptData(byte[] input) throws Exception {
return encryptData(input DEFAULT_KEY)
}
/**
* 将给定的已加密的数据通过指定的密钥进行解密
*
* @param input
* 待解密的数据
* @param key
* 密钥
* @return byte[] 解密后的数据
* @throws Exception
*/
public static byte[] decryptData(byte[] input byte[] key) throws Exception {
SecretKey deskey = new javax crypto spec SecretKeySpec(key Algorithm)
// if (debug ) System out println ( 解密前的信息 +byte hex (input ))
Cipher c = Cipher getInstance(Algorithm)
c init(Cipher DECRYPT_MODE deskey)
byte[] clearByte = c doFinal(input)
// if (debug )
// {
// System out println ( 解密后的二进串 +byte hex (clearByte ))
// System out println ( 解密后的字符串 +(new String (clearByte )))
//
// }
return clearByte;
}
public static byte[] decryptData(byte[] input) throws Exception {
return decryptData(input DEFAULT_KEY)
}
/**
* 字节码转换成 进制字符串
*
* @param byte[] b 输入要转换的字节码
* @return String 返回转换后的 进制字符串
*/
public static String byte hex(byte[] bytes) {
StringBuilder hs = new StringBuilder()
for(byte b : bytes)
hs append(String format( % $ X b))
return hs toString()
}
public static byte[] hex byte(String content) {
int l=content length()》 ;
byte[] result=new byte[l];
for(int i= ;il;i++) {
int j=i《 ;
String s=content substring(j j+ )
result[i]=Integer valueOf(s ) byteValue()
}
return result;
}
/**
* 将字节数组转换为base 编码字符串
* @param buffer
* @return
*/
public static String bytesToBase (byte[] buffer) {
//BASE Encoder en=new BASE Encoder()
return Base encode(buffer)
// return encoder encode(buffer)
}
/**
* 将base 编码的字符串解码为字节数组
* @param value
* @return
* @throws IOException
*/
public static byte[] base ToBytes(String value) throws IOException {
//return Base decodeToByteArray(value)
// System out println(decoder decodeBuffer(value))
// return decoder decodeBuffer(value)
return Base decode(value)
}
/**
* 加密给定的字符串
* @param value
* @return 加密后的base 字符串
*/
public static String encryptString(String value) {
return encryptString(value DEFAULT_KEY)
}
/**
* 根据给定的密钥加密字符串
* @param value 待加密的字符串
* @param key 以BASE 形式存在的密钥
* @return 加密后的base 字符串
* @throws IOException
*/
public static String encryptString(String value String key) throws IOException {
return encryptString(value base ToBytes(key))
}
/**
* 根据给定的密钥加密字符串
* @param value 待加密的字符串
* @param key 字节数组形式的密钥
* @return 加密后的base 字符串
*/
public static String encryptString(String value byte[] key) {
try {
byte[] data=value getBytes(VALUE_ENCODING)
data=CryptUtils encryptData(data key)
return bytesToBase (data)
} catch (Exception e) {
// TODO Auto generated catch block
e printStackTrace()
return null;
}
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @return 明文
*/
public static String decryptString(String value) {
return decryptString(value DEFAULT_KEY)
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @param key base 形式存在的密钥
* @return 明文
* @throws IOException
*/
public static String decryptString(String value String key) throws IOException {
String s=decryptString(value base ToBytes(key))
return s;
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @param key 字节数据形式存在的密钥
* @return 明文
*/
public static String decryptString(String value byte[] key) {
try {
byte[] data=base ToBytes(value)
data=CryptUtils decryptData(data key)
return new String(data VALUE_ENCODING)
}catch(Exception e) {
e printStackTrace()
return null;
}
}
}
package gdie lab crypt;
import java io IOException;
import javax crypto Cipher;
import javax crypto KeyGenerator;
import javax crypto SecretKey;
import apache xerces internal impl dv util Base ;
public class CryptUtils {
private static String Algorithm = DES ;
private static byte[] DEFAULT_KEY=new byte[] { };
private static String VALUE_ENCODING= UTF ;
/**
* 生成密钥
*
* @return byte[] 返回生成的密钥
* @throws exception
* 扔出异常
*/
public static byte[] getSecretKey() throws Exception {
KeyGenerator keygen = KeyGenerator getInstance(Algorithm)
SecretKey deskey = keygen generateKey()
// if (debug ) System out println ( 生成密钥 +byte hex (deskey getEncoded
// ()))
return deskey getEncoded()
}
/**
* 将指定的数据根据提供的密钥进行加密
*
* @param input
* 需要加密的数据
* @param key
* 密钥
* @return byte[] 加密后的数据
* @throws Exception
*/
public static byte[] encryptData(byte[] input byte[] key) throws Exception {
SecretKey deskey = new javax crypto spec SecretKeySpec(key Algorithm)
// if (debug )
// {
// System out println ( 加密前的二进串 +byte hex (input ))
// System out println ( 加密前的字符串 +new String (input ))
//
// }
Cipher c = Cipher getInstance(Algorithm)
c init(Cipher ENCRYPT_MODE deskey)
byte[] cipherByte = c doFinal(input)
// if (debug ) System out println ( 加密后的二进串 +byte hex (cipherByte ))
return cipherByte;
}
public static byte[] encryptData(byte[] input) throws Exception {
return encryptData(input DEFAULT_KEY)
}
/**
* 将给定的已加密的数据通过指定的密钥进行解密
*
* @param input
* 待解密的数据
* @param key
* 密钥
* @return byte[] 解密后的数据
* @throws Exception
*/
public static byte[] decryptData(byte[] input byte[] key) throws Exception {
SecretKey deskey = new javax crypto spec SecretKeySpec(key Algorithm)
// if (debug ) System out println ( 解密前的信息 +byte hex (input ))
Cipher c = Cipher getInstance(Algorithm)
c init(Cipher DECRYPT_MODE deskey)
byte[] clearByte = c doFinal(input)
// if (debug )
// {
// System out println ( 解密后的二进串 +byte hex (clearByte ))
// System out println ( 解密后的字符串 +(new String (clearByte )))
//
// }
return clearByte;
}
public static byte[] decryptData(byte[] input) throws Exception {
return decryptData(input DEFAULT_KEY)
}
/**
* 字节码转换成 进制字符串
*
* @param byte[] b 输入要转换的字节码
* @return String 返回转换后的 进制字符串
*/
public static String byte hex(byte[] bytes) {
StringBuilder hs = new StringBuilder()
for(byte b : bytes)
hs append(String format( % $ X b))
return hs toString()
}
public static byte[] hex byte(String content) {
int l=content length()》 ;
byte[] result=new byte[l];
for(int i= ;il;i++) {
int j=i《 ;
String s=content substring(j j+ )
result[i]=Integer valueOf(s ) byteValue()
}
return result;
}
/**
* 将字节数组转换为base 编码字符串
* @param buffer
* @return
*/
public static String bytesToBase (byte[] buffer) {
//BASE Encoder en=new BASE Encoder()
return Base encode(buffer)
// return encoder encode(buffer)
}
/**
* 将base 编码的字符串解码为字节数组
* @param value
* @return
* @throws IOException
*/
public static byte[] base ToBytes(String value) throws IOException {
//return Base decodeToByteArray(value)
// System out println(decoder decodeBuffer(value))
// return decoder decodeBuffer(value)
return Base decode(value)
}
/**
* 加密给定的字符串
* @param value
* @return 加密后的base 字符串
*/
public static String encryptString(String value) {
return encryptString(value DEFAULT_KEY)
}
/**
* 根据给定的密钥加密字符串
* @param value 待加密的字符串
* @param key 以BASE 形式存在的密钥
* @return 加密后的base 字符串
* @throws IOException
*/
public static String encryptString(String value String key) throws IOException {
return encryptString(value base ToBytes(key))
}
/**
* 根据给定的密钥加密字符串
* @param value 待加密的字符串
* @param key 字节数组形式的密钥
* @return 加密后的base 字符串
*/
public static String encryptString(String value byte[] key) {
try {
byte[] data=value getBytes(VALUE_ENCODING)
data=CryptUtils encryptData(data key)
return bytesToBase (data)
} catch (Exception e) {
// TODO Auto generated catch block
e printStackTrace()
return null;
}
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @return 明文
*/
public static String decryptString(String value) {
return decryptString(value DEFAULT_KEY)
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @param key base 形式存在的密钥
* @return 明文
* @throws IOException
*/
public static String decryptString(String value String key) throws IOException {
String s=decryptString(value base ToBytes(key))
return s;
}
/**
* 解密字符串
* @param value base 形式存在的密文
* @param key 字节数据形式存在的密钥
* @return 明文
*/
public static String decryptString(String value byte[] key) {
try {
byte[] data=base ToBytes(value)
data=CryptUtils decryptData(data key)
return new String(data VALUE_ENCODING)
}catch(Exception e) {
e printStackTrace()
return null;
}
}
}
CryptHelper java
[java]
package gdie lab crypt;
import javax crypto Cipher;
import javax crypto SecretKey;
import javax crypto SecretKeyFactory;
import javax crypto spec DESKeySpec;
import javax crypto spec IvParameterSpec;
import springframework util DigestUtils;
public class CryptHelper{
private static String CRYPT_KEY = zhongqian ;
//加密
private static Cipher ecip;
//解密
private static Cipher dcip;
static {
try {
String KEY = DigestUtils md DigestAsHex(CRYPT_KEY getBytes()) toUpperCase()
KEY = KEY substring( )
byte[] bytes = KEY getBytes()
DESKeySpec ks = new DESKeySpec(bytes)
SecretKeyFactory skf = SecretKeyFactory getInstance( DES )
SecretKey sk = skf generateSecret(ks)
IvParameterSpec iv = new IvParameterSpec(bytes)
ecip = Cipher getInstance( DES/CBC/PKCS Padding )
ecip init(Cipher ENCRYPT_MODE sk iv )
dcip = Cipher getInstance( DES/CBC/PKCS Padding )
dcip init(Cipher DECRYPT_MODE sk iv )
}catch(Exception ex) {
ex printStackTrace()
}
}
public static String encrypt(String content) throws Exception {
byte[] bytes = ecip doFinal(content getBytes( ascii ))
return CryptUtils byte hex(bytes)
}
public static String decrypt(String content) throws Exception {
byte[] bytes = CryptUtils hex byte(content)
bytes = dcip doFinal(bytes)
return new String(bytes ascii )
}
//test
public static void main(String[] args) throws Exception {
String password = gly ;
String en = encrypt(password)
System out println(en)
System out println(decrypt(en))
}
}
package gdie lab crypt;
import javax crypto Cipher;
import javax crypto SecretKey;
import javax crypto SecretKeyFactory;
import javax crypto spec DESKeySpec;
import javax crypto spec IvParameterSpec;
import springframework util DigestUtils;
public class CryptHelper{
private static String CRYPT_KEY = zhongqian ;
//加密
private static Cipher ecip;
//解密
private static Cipher dcip;
static {
try {
String KEY = DigestUtils md DigestAsHex(CRYPT_KEY getBytes()) toUpperCase()
KEY = KEY substring( )
byte[] bytes = KEY getBytes()
DESKeySpec ks = new DESKeySpec(bytes)
SecretKeyFactory skf = SecretKeyFactory getInstance( DES )
SecretKey sk = skf generateSecret(ks)
IvParameterSpec iv = new IvParameterSpec(bytes)
ecip = Cipher getInstance( DES/CBC/PKCS Padding )
ecip init(Cipher ENCRYPT_MODE sk iv )
dcip = Cipher getInstance( DES/CBC/PKCS Padding )
dcip init(Cipher DECRYPT_MODE sk iv )
}catch(Exception ex) {
ex printStackTrace()
}
}
public static String encrypt(String content) throws Exception {
byte[] bytes = ecip doFinal(content getBytes( ascii ))
return CryptUtils byte hex(bytes)
}
public static String decrypt(String content) throws Exception {
byte[] bytes = CryptUtils hex byte(content)
bytes = dcip doFinal(bytes)
return new String(bytes ascii )
}
//test
public static void main(String[] args) throws Exception {
String password = gly ;
String en = encrypt(password)
System out println(en)
System out println(decrypt(en))
}
lishixinzhi/Article/program/Java/hx/201311/26449
基本的单向加密算法:
BASE64 严格地说,属于编码格式,而非加密算法
MD5(Message Digest algorithm 5,信息摘要算法)
SHA(Secure Hash Algorithm,安全散列算法)
HMAC(Hash Message Authentication Code,散列消息鉴别码)
复杂的对称加密(DES、PBE)、非对称加密算法:
DES(Data Encryption Standard,数据加密算法)
PBE(Password-based encryption,基于密码验证)
RSA(算法的名字以发明者的名字命名:Ron Rivest, AdiShamir 和Leonard Adleman)
DH(Diffie-Hellman算法,密钥一致协议)
DSA(Digital Signature Algorithm,数字签名)
ECC(Elliptic Curves Cryptography,椭圆曲线密码编码学)
代码参考:
/**
* BASE64加密
*
* @param key
* @return
* @throws Exception
*/
public static String encryptBASE64(byte[] key) throws Exception {
return (new BASE64Encoder()).encodeBuffer(key);
}
/**
* MD5加密
*
* @param data
* @return
* @throws Exception
*/
public static byte[] encryptMD5(byte[] data) throws Exception {
MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);
md5.update(data);
return md5.digest();
}
/**
* SHA加密
*
* @param data
* @return
* @throws Exception
*/
public static byte[] encryptSHA(byte[] data) throws Exception {
MessageDigest sha = MessageDigest.getInstance(KEY_SHA);
sha.update(data);
return sha.digest();
}
}
/**
* 初始化HMAC密钥
*
* @return
* @throws Exception
*/
public static String initMacKey() throws Exception {
KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);
SecretKey secretKey = keyGenerator.generateKey();
return encryptBASE64(secretKey.getEncoded());
}
/**
* HMAC加密
*
* @param data
* @param key
* @return
* @throws Exception
*/
public static byte[] encryptHMAC(byte[] data, String key) throws Exception {
SecretKey secretKey = new SecretKeySpec(decryptBASE64(key), KEY_MAC);
Mac mac = Mac.getInstance(secretKey.getAlgorithm());
mac.init(secretKey);
return mac.doFinal(data);
}
加密解密并非java才有的,所有编程语言都有加密和解密。
目前的加密解密主要可分为以下2大类:
对称秘钥加密:如DES算法,3DES算法,TDEA算法,Blowfish算法,RC5算法,IDEA算法等。其主要特点是加密方和解密方都有同一个密码,加密方和解密方可以使用秘钥任意加密解密。
非对称密码加密:这种加密方式加密方仅有加密秘钥,对加密后的密文无法反向解密,解密方仅有解密秘钥,无法对明文进行加密。
另外还有一些摘要算法,比如MD5和HASH此类算法不可逆,但经常用来作为确认字段或者对一些重要匹配信息签名防止明文内容被修改。