java密碼加密與解密

以下兩個類可以很方便的完成字串的加密和解密：

加密：CryptHelper.encrypt(password)

解密：CrypHelper.decrypt(password)

 

代碼如下：

CryptUtils.java

package com.gdie.lab.crypt;import java.io.IOException;import javax.crypto.Cipher;import javax.crypto.KeyGenerator;import javax.crypto.SecretKey;import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;public class CryptUtils {private static String Algorithm = "DES";private static byte[] DEFAULT_KEY=new byte[] {-53, 122, -42, -88, -110, -123, -60, -74};private static String VALUE_ENCODING="UTF-8";/** * 產生密鑰 *  * @return byte[] 返回產生的密鑰 * @throws exception *             扔出異常. */public static byte[] getSecretKey() throws Exception {KeyGenerator keygen = KeyGenerator.getInstance(Algorithm);SecretKey deskey = keygen.generateKey();// if (debug ) System.out.println ("產生密鑰:"+byte2hex (deskey.getEncoded// ()));return deskey.getEncoded();}/** * 將指定的資料根據提供的密鑰進行加密 *  * @param input *            需要加密的資料 * @param key *            密鑰 * @return byte[] 加密後的資料 * @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 ("加密前的二進串:"+byte2hex (input ));// System.out.println ("加密前的字串:"+new String (input ));//// }Cipher c1 = Cipher.getInstance(Algorithm);c1.init(Cipher.ENCRYPT_MODE, deskey);byte[] cipherByte = c1.doFinal(input);// if (debug ) System.out.println ("加密後的二進串:"+byte2hex (cipherByte ));return cipherByte;}public static byte[] encryptData(byte[] input) throws Exception {return encryptData(input, DEFAULT_KEY);}/** * 將給定的已加密的資料通過指定的密鑰進行解密 *  * @param input *            待解密的資料 * @param key *            密鑰 * @return byte[] 解密後的資料 * @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 ("解密前的資訊:"+byte2hex (input ));Cipher c1 = Cipher.getInstance(Algorithm);c1.init(Cipher.DECRYPT_MODE, deskey);byte[] clearByte = c1.doFinal(input);// if (debug )// {// System.out.println ("解密後的二進串:"+byte2hex (clearByte ));// System.out.println ("解密後的字串:"+(new String (clearByte )));//// }return clearByte;}public static byte[] decryptData(byte[] input) throws Exception {return decryptData(input, DEFAULT_KEY);}/** * 位元組碼轉換成16進位字串 *  * @param byte[] b 輸入要轉換的位元組碼 * @return String 返迴轉換後的16進位字串 */public static String byte2hex(byte[] bytes) {StringBuilder hs = new StringBuilder();for(byte b : bytes)hs.append(String.format("%1$02X", b));return hs.toString();}public static byte[] hex2byte(String content) {int l=content.length()>>1;byte[] result=new byte[l];for(int i=0;i<l;i++) {int j=i<<1;String s=content.substring(j, j+2);result[i]=Integer.valueOf(s, 16).byteValue();}return result;}/** * 將位元組數群組轉換為base64編碼字串 * @param buffer * @return */public static String bytesToBase64(byte[] buffer) {//BASE64Encoder en=new BASE64Encoder();return Base64.encode(buffer);//return encoder.encode(buffer);}/** * 將base64編碼的字串解碼為位元組數組 * @param value * @return * @throws IOException  */public static byte[] base64ToBytes(String value) throws IOException {//return Base64.decodeToByteArray(value);//System.out.println(decoder.decodeBuffer(value));//return decoder.decodeBuffer(value);return Base64.decode(value);}/** * 加密給定的字串 * @param value * @return 加密後的base64字串 */public static String encryptString(String value) {return encryptString(value, DEFAULT_KEY);}/** * 根據給定的祕密金鑰加密字串 * @param value 待加密的字串 * @param key 以BASE64形式存在的密鑰 * @return 加密後的base64字串 * @throws IOException  */public static String encryptString(String value, String key) throws IOException {return encryptString(value, base64ToBytes(key));}/** * 根據給定的祕密金鑰加密字串 * @param value 待加密的字串 * @param key 位元組數組形式的密鑰 * @return 加密後的base64字串 */public static String encryptString(String value, byte[] key) {try {byte[] data=value.getBytes(VALUE_ENCODING);data=CryptUtils.encryptData(data, key);return bytesToBase64(data);} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();return null;}}/** * 解密字串 * @param value base64形式存在的密文 * @return 明文 */public static String decryptString(String value) {return decryptString(value, DEFAULT_KEY);}/** * 解密字串 * @param value base64形式存在的密文 * @param key base64形式存在的密鑰 * @return 明文 * @throws IOException  */public static String decryptString(String value, String key) throws IOException {String s=decryptString(value, base64ToBytes(key));return s; }/** * 解密字串 * @param value base64形式存在的密文 * @param key 位元組資料形式存在的密鑰 * @return 明文 */public static String decryptString(String value, byte[] key) {try {byte[] data=base64ToBytes(value);data=CryptUtils.decryptData(data, key);return new String(data, VALUE_ENCODING);}catch(Exception e) {e.printStackTrace();return null;}}}

 

CryptHelper.java

package com.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 org.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.md5DigestAsHex(CRYPT_KEY.getBytes()).toUpperCase();KEY = KEY.substring(0, 8);byte[] bytes = KEY.getBytes();DESKeySpec ks = new DESKeySpec(bytes); SecretKeyFactory skf = SecretKeyFactory.getInstance("DES"); SecretKey sk = skf.generateSecret(ks); IvParameterSpec iv2 = new IvParameterSpec(bytes); ecip = Cipher.getInstance("DES/CBC/PKCS5Padding");ecip.init(Cipher.ENCRYPT_MODE, sk, iv2);dcip = Cipher.getInstance("DES/CBC/PKCS5Padding");dcip.init(Cipher.DECRYPT_MODE, sk, iv2);}catch(Exception ex) {ex.printStackTrace();}}public static String encrypt(String content) throws Exception {byte[] bytes = ecip.doFinal(content.getBytes("ascii"));return CryptUtils.byte2hex(bytes);}public static String decrypt(String content) throws Exception {byte[] bytes  = CryptUtils.hex2byte(content);bytes = dcip.doFinal(bytes);return new String(bytes, "ascii");}//testpublic static void main(String[] args) throws Exception {String password = "gly";String en = encrypt(password);System.out.println(en);System.out.println(decrypt(en));}}