利用AES加密解密（Java&跨平台）

• 配置文件中保存明文密码显得不那么安全，这里解决这个问题。配置文件中保存加密后的密文，在使用的时候再解密还原。

• java.util.Base64是Java 1.8新增的，如果jdk版本低于1.8，请更换成其他的Base64工具。

    import java.io.UnsupportedEncodingException;
    import java.security.InvalidKeyException;
    import java.security.NoSuchAlgorithmException;
    import java.security.SecureRandom;
    import java.util.Base64;
  
    import javax.crypto.BadPaddingException;
    import javax.crypto.Cipher;
    import javax.crypto.IllegalBlockSizeException;
    import javax.crypto.KeyGenerator;
    import javax.crypto.NoSuchPaddingException;
    import javax.crypto.spec.SecretKeySpec;
  
    public class EncryptUtils {
  
    	/**
    	 * AES加密
    	 *
    	 * [@param](https://my.oschina.net/u/2303379) ciphertext
    	 *            待加密的内容
    	 * [@param](https://my.oschina.net/u/2303379) encryptKey
    	 *            加密密钥
    	 * [@return](https://my.oschina.net/u/556800) 加密后的byte[]
    	 */
    	public static byte[] aesEncryptToBytes(String ciphertext, String encryptKey) {
    		try {
    			return getCipher(Cipher.ENCRYPT_MODE, encryptKey).doFinal(
    					ciphertext.getBytes("utf-8"));
    		} catch (IllegalBlockSizeException e) {
    			e.printStackTrace();
    			return null;
    		} catch (BadPaddingException e) {
    			e.printStackTrace();
    			return null;
    		} catch (UnsupportedEncodingException e) {
    			e.printStackTrace();
    			return null;
    		} catch (NoSuchAlgorithmException e) {
    			e.printStackTrace();
    			return null;
    		}
    	}
  
    	/**
    	 * AES解密
    	 *
    	 * [@param](https://my.oschina.net/u/2303379) encryptBytes
    	 *            待解密的byte[]
    	 * [@param](https://my.oschina.net/u/2303379) decryptKey
    	 *            解密密钥
    	 * @return 解密后的String
    	 */
    	public static String aesDecryptByBytes(byte[] encryptBytes,
    			String decryptKey) {
    		byte[] decryptBytes;
    		try {
    			decryptBytes = getCipher(Cipher.DECRYPT_MODE, decryptKey).doFinal(
    					encryptBytes);
    		} catch (IllegalBlockSizeException e) {
    			e.printStackTrace();
    			return null;
    		} catch (BadPaddingException e) {
    			e.printStackTrace();
    			return null;
    		} catch (NoSuchAlgorithmException e) {
    			e.printStackTrace();
    			return null;
    		}
  
    		return new String(decryptBytes);
    	}
  
    	private static Cipher getCipher(int cipherMode, String encryptKey) throws NoSuchAlgorithmException {
    		KeyGenerator kgen;
    		SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
    		random.setSeed(encryptKey.getBytes());
    		try {
    			kgen = KeyGenerator.getInstance("AES");
    		} catch (NoSuchAlgorithmException e) {
    			e.printStackTrace();
    			return null;
    		}
    		kgen.init(128, random);
    		Cipher cipher;
    		try {
    			cipher = Cipher.getInstance("AES");
    		} catch (NoSuchAlgorithmException e) {
    			e.printStackTrace();
    			return null;
    		} catch (NoSuchPaddingException e) {
    			e.printStackTrace();
    			return null;
    		}
    		try {
    			cipher.init(cipherMode, new SecretKeySpec(kgen.generateKey()
    					.getEncoded(), "AES"));
    		} catch (InvalidKeyException e) {
    			e.printStackTrace();
    			return null;
    		}
    		return cipher;
    	}
  
    	/**
    	 * 根据传入的内容和密钥，返回加密后得到的base64字符串
    	 *
    	 * @author ChangJian
    	 * @data 2018年7月25日
    	 * @param ciphertext
    	 *            待加密的内容
    	 * @param encryptKey
    	 *            密钥
    	 * @return
    	 */
    	public static String encryptAesBase64(String ciphertext, String encryptKey) {
    		return Base64.getEncoder().encodeToString(aesEncryptToBytes(ciphertext, encryptKey));
    	}
  
    	/**
    	 * 把encryptAesBase64方法生成的base64形式的密码还原成明文密码
    	 *
    	 * @author ChangJian
    	 * @data 2018年7月25日
    	 * @param ciphertext
    	 *            base64形式的密码
    	 * @param decryptKey
    	 *            解密的密钥
    	 * @return
    	 */
    	public static String decryptAesBase64(String ciphertext, String decryptKey) {
    		return aesDecryptByBytes(Base64.getDecoder().decode(ciphertext), decryptKey);
    	}
  
    	/**
    	 * 测试
    	 */
    	public static void main(String[] args) {
    		String password = "password123456";
    		String decryptKey = "8F85C42859C4B883817EB72E37AF2A3E";
    		String ciphertext = encryptAesBase64(password, decryptKey);
    		System.out.println("密文：" + ciphertext);
    		System.out.println("解密：" + decryptAesBase64(ciphertext, decryptKey));
    	}
    }