浅析Java 常用的 4 种加密方式（MD5+Base64+SHA+BCrypt）

 public class MD5Utils { private static final String hexDigIts[] = {"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"}; /** * MD5加密 * @param origin 字符 * @param charsetname 编码 * @return */ public static String MD5Encode(String origin, String charsetname){ String resultString = null; try{ resultString = new String(origin); MessageDigest md = MessageDigest.getInstance("MD5"); if(null == charsetname || "".equals(charsetname)){ resultString = byteArrayToHexString(md.digest(resultString.getBytes())); }else{ resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname))); } }catch (Exception e){ } return resultString; } public static String byteArrayToHexString(byte b[]){ StringBuffer resultSb = new StringBuffer(); for(int i = 0; i <b.length; i++){ resultSb.append(byteToHexString(b[i])); } return resultSb.toString(); } public static String byteToHexString(byte b){ int n = b; if(n <0){ n += 256; } int d1 = n / 16; int d2 = n % 16; return hexDigIts[d1] + hexDigIts[d2]; } }

 public class Base64Util { // 字符串编码 private static final String UTF_8 = "UTF-8"; /** * 加密字符串 * @param inputData * @return */ public static String decodeData(String inputData) { try { if (null == inputData) { return null; } return new String(Base64.decodeBase64(inputData.getBytes(UTF_8)), UTF_8); } catch (UnsupportedEncodingException e) { } return null; } /** * 解密加密后的字符串 * @param inputData * @return */ public static String encodeData(String inputData) { try { if (null == inputData) { return null; } return new String(Base64.encodeBase64(inputData.getBytes(UTF_8)), UTF_8); } catch (UnsupportedEncodingException e) { } return null; } public static void main(String[] args) { System.out.println(Base64Util.encodeData("我是中文")); String enStr = Base64Util.encodeData("我是中文"); System.out.println(Base64Util.decodeData(enStr)); } }

 public class BcryptCipher { // generate salt seed private static final int SALT_SEED = 12; // the head fo salt private static final String SALT_STARTSWITH = "$2a$12"; public static final String SALT_KEY = "salt"; public static final String CIPHER_KEY = "cipher"; /** * Bcrypt encryption algorithm method * @param encryptSource * need to encrypt the string * @return Map , two values in Map , salt and cipher */ public static Map Bcrypt(final String encryptSource) { String salt = BCrypt.gensalt(SALT_SEED); Map bcryptResult = Bcrypt(salt, encryptSource); return bcryptResult; } /** * * @param salt encrypt salt, Must conform to the rules * @param encryptSource * @return */ public static Map Bcrypt(final String salt, final String encryptSource) { if (StringUtils.isBlank(encryptSource)) { throw new RuntimeException("Bcrypt encrypt input params can not be empty"); } if (StringUtils.isBlank(salt) || salt.length() != 29) { throw new RuntimeException("Salt can't be empty and length must be to 29"); } if (!salt.startsWith(SALT_STARTSWITH)) { throw new RuntimeException("Invalid salt version, salt version is $2a$12"); } String cipher = BCrypt.hashpw(encryptSource, salt); Map bcryptResult = new HashMap(); bcryptResult.put(SALT_KEY, salt); bcryptResult.put(CIPHER_KEY, cipher); return bcryptResult; } }

 /** * MD5加密 */ public class MD5Test { public static void main(String[] args) { String string = "你好 世界"; String byteArrayToHexString = MD5Utils.byteArrayToHexString(string.getBytes()); System.out.println(byteArrayToHexString);//e68891e698afe4b880e58fa5e8af9d } }

 /** * base64加密 */ public class Bast64Tester { public static void main(String[] args) { String string = "你好 世界"; String encodeData = Base64Util.encodeData(string); //加密 String decodeData = Base64Util.decodeData(encodeData); //解密 System.out.println(encodeData);//5oiR5piv5LiA5Liq5a2X56ym5Liy System.out.println(decodeData);//你好 世界 } }

 /** * SHA加密 */ public class ShaTest { public static void main(String[] args) { String string = "你好 世界"; String sha256Crypt = Sha2Crypt.sha256Crypt(string.getBytes()); System.out.println(sha256Crypt);//$5$AFoQTeyt$TiqmobvcQXjXaAQMYosAAO4KI8LfigZMGHzq.Dlp4NC } }

 /** * BCrypt加密 */ public class BCryptTest { public static void main(String[] args) { String string = "你好世界"; Map bcrypt = BcryptCipher.Bcrypt(string); System.out.println(bcrypt.keySet()); //[cipher, salt] System.out.printl<p style="color:transparent">来源gao!%daima.com搞$代*!码$网</p>n(bcrypt.get("cipher")); //$2a$12$ylb92Z84gqlrSfzIztlCV.dK0xNbw.pOv3UwXXA76llOsNRTJsE/. System.out.println(bcrypt.get("salt")); //$2a$12$ylb92Z84gqlrSfzIztlCV. Map bcrypt2 = BcryptCipher.Bcrypt(bcrypt.get("salt"),string); System.out.println(bcrypt2.get("SALT_KEY")); //null System.out.println(bcrypt2.get("CIPHER_KEY")); //null } }