各种加密 解密 Java实现代码

AES

public class AESCoder {
	
	public static final String ALGORITHM = "AES";
	
	public static final String CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";
	
	public static byte[] initKey(){
		try {
			KeyGenerator keyGenerator = KeyGenerator.getInstance(ALGORITHM);
			keyGenerator.init(128);
			
			return keyGenerator.generateKey().getEncoded();
		} catch (NoSuchAlgorithmException e) {
			throw new RuntimeException(e.getMessage(), e);
		}
	}
	
	
	private static Key toKey(byte[] key){
		return new SecretKeySpec(key, ALGORITHM);
	}
	
	public static String encrypt(String data, byte[] k) throws Exception {
		Key key = toKey(k);
		Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
		//初始化, 设置为加密模式
		cipher.init(Cipher.ENCRYPT_MODE, key);
		byte[] enBytes = cipher.doFinal(data.getBytes());
		return new BASE64Encoder().encode(enBytes);
	}
	
	public static String decrypt(String data, byte[] k) throws Exception{
		Key key = toKey(k);
		Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
		//初始化, 设置为解密模式
		cipher.init(Cipher.DECRYPT_MODE, key);
		byte[] bytes = cipher.doFinal(new BASE64Decoder().decodeBuffer(data));
		return new String(bytes);
	}
	
	public static void main(String[] args) throws Exception{
		String inputStr = "张三";
		byte[] k = AESCoder.initKey();
		System.out.println("密钥: " + String.valueOf(Hex.encodeHex(k)));
		String en = AESCoder.encrypt(inputStr, k);
		System.out.println("密文: " + en);
		
		//解密
		String de = AESCoder.decrypt(en, k);
		System.out.println("解密后明文: " + new String(de));
	}
}

HmacMD5

public class MACEncoder {
	
	public static final String ALGORITHM = "HmacMD5";
	
	public static byte[] initHmacMD5Key() throws Exception{
		KeyGenerator keyGenerator = KeyGenerator.getInstance(ALGORITHM);
		SecretKey secretKey = keyGenerator.generateKey();
		return secretKey.getEncoded();
	}
	
	public static byte[] encodeHmacMD5(byte[] data, byte[] key) throws Exception{
		SecretKey secretKey = new SecretKeySpec(key, ALGORITHM);
		Mac mac = Mac.getInstance(secretKey.getAlgorithm());
		mac.init(secretKey);
		return mac.doFinal(data);
	}
	
	
	public static void main(String[] args) throws Exception{
		String id = "13141283947192347174";
		String key = "11";
		long t1 = System.currentTimeMillis();
		System.out.println(encodeHmacMD5(id, key));
		System.out.println(encodeHmacMD5(id, key));
		System.out.println(encodeHmacMD5(id, key));
		System.out.println(encodeHmacMD5(id, key));
		System.out.println(System.currentTimeMillis() - t1);
		//System.out.println(Hex.encodeHex(initHmacMD5Key()));
	}
	
	public static String encodeHmacMD5(String data, String key) throws Exception{
		
		SecretKey secretKey = new SecretKeySpec(Hex.decodeHex(key.toCharArray()), "HmacMD5");
		Mac mac = Mac.getInstance(secretKey.getAlgorithm());
		mac.init(secretKey);
		return String.valueOf(Hex.encodeHex(mac.doFinal(data.getBytes())));
	}
	
}

MD5

public class MD5Encoder2 {
	
	public static void main(String[] args) {
		String str = "12345";
		try {
			MessageDigest digest = MessageDigest.getInstance("MD5");
			byte[] bytes = digest.digest(str.getBytes());
			System.out.println(Hex.encodeHex(bytes));
		} catch (Exception e) {
			e.printStackTrace();
		} 
	}
	
	
	
}

RSA

public class RSAEncoder {
	
	public static final String ALGORITHM = "rsa";
	
	public static final String PUBLIC_KEY = "RSAPublicKey";
	
	public static final String PRIVATE_KEY = "RSAPrivateKey";
	
	public static final int KEY_SIZE = 512;
	
	/**
	 * 私钥解密
	 * @param data
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] decryptByPrivateKey(byte[] data, byte[] key) throws Exception{
		PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(key);
		KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
		PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
		
		Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
		cipher.init(Cipher.DECRYPT_MODE, privateKey);
		return cipher.doFinal(data);
	}
	
	/**
	 * 公钥加密
	 * @param data
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] encryptByPublicKey(byte[] data, byte[] key) throws Exception{
		X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(key);
		KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
		PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
		Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
		cipher.init(Cipher.ENCRYPT_MODE, publicKey);
		return cipher.doFinal(data);
	}
	
	/**
	 * 公钥加密
	 * @param data
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] encryptByPublicKey(byte[] data, PublicKey publicKey) throws Exception {
		KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
		Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
		cipher.init(Cipher.ENCRYPT_MODE, publicKey);
		return cipher.doFinal(data);
	}
	
	/**
	 * 公钥解密
	 * @param data
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] decryptByPublicKey(byte[] data, byte[] key) throws Exception{
		X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(key);
		KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
		PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
		Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
		cipher.init(Cipher.DECRYPT_MODE, publicKey);
		return cipher.doFinal(data);
	}
	
	/**
	 * 私钥加密
	 * @param data
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] encryptByPrivateKey(byte[] data, byte[] key) throws Exception{
		PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(key);
		KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
		PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
		
		Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
		cipher.init(Cipher.ENCRYPT_MODE, privateKey);
		return cipher.doFinal(data);
	}
	
	/**
	 * 初始化密钥
	 * @return
	 * @throws Exception
	 */
	public static KeyPair initKey() throws Exception{
		KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(ALGORITHM);
		KeyPair keyPair = keyPairGenerator.generateKeyPair();
		return keyPair;
	}
	
	public static void main(String[] args) throws Exception{
		KeyPair keyPair = initKey();//密钥对
		String data = "明文数据12345";
		
		System.out.println("私钥: " + String.valueOf(Hex.encodeHex(keyPair.getPrivate().getEncoded())));
		System.out.println("公钥: " + String.valueOf(Hex.encodeHex(keyPair.getPublic().getEncoded())));
		
		byte[] byte1 = encryptByPublicKey(data.getBytes(), keyPair.getPublic().getEncoded());
		System.out.println("公钥加密后: " + String.valueOf(Hex.encodeHex(byte1)));
		
		byte[] byte2 = decryptByPrivateKey(byte1, keyPair.getPrivate().getEncoded());
		System.out.println("私钥解密后: " + new String(byte2));
		
		byte[] byte3 = encryptByPrivateKey(data.getBytes(), keyPair.getPrivate().getEncoded());
		System.out.println("私钥加密后: " + String.valueOf(Hex.encodeHex(byte3)));
		
		byte[] byte4 = decryptByPublicKey(byte3, keyPair.getPublic().getEncoded());
		System.out.println("公钥解密后: " + new String(byte4));
	}
	
}