AES加密

时间:2022-05-04
本文章向大家介绍AES加密,主要内容包括其使用实例、应用技巧、基本知识点总结和需要注意事项,具有一定的参考价值,需要的朋友可以参考一下。
package com.test.util.encrypt;

import org.apache.commons.lang3.StringUtils;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.SecretKeySpec;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.SecureRandom;

/**
 * 一些简单的编码测试
 * Created by miaorf on 2016/4/24.
 */
public class AESEncrypt {
    public static void main(String[] args) throws Exception {
        String content = "我爱你";
        System.out.println("加密前:" + content);

        String key = "123456";
        System.out.println("加密密钥和解密密钥:" + key);

        String encrypt = aesEncrypt(content, key);
        System.out.println("加密后:" + encrypt);

        String decrypt = aesDecrypt(encrypt, key);
        System.out.println("解密后:" + decrypt);
    }
    
    /**
     * base 64 encode
     *
     * @param bytes 待编码的byte[]
     * @return 编码后的base 64 code
     */
    public static String base64Encode(byte[] bytes) {
        return new BASE64Encoder().encode(bytes);
    }

    /**
     * base 64 decode
     *
     * @param base64Code 待解码的base 64 code
     * @return 解码后的byte[]
     * @throws Exception
     */
    public static byte[] base64Decode(String base64Code) throws Exception {
        return StringUtils.isEmpty(base64Code) ? null : new BASE64Decoder().decodeBuffer(base64Code);
    }

    /**
     * AES加密
     *
     * @param content    待加密的内容
     * @param encryptKey 加密密钥
     * @return 加密后的byte[]
     * @throws Exception
     */
    public static byte[] aesEncryptToBytes(String content, String encryptKey) throws Exception {
        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        kgen.init(128, new SecureRandom(encryptKey.getBytes()));

        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(kgen.generateKey().getEncoded(), "AES"));

        return cipher.doFinal(content.getBytes("utf-8"));
    }

    /**
     * AES加密为base 64 code
     *
     * @param content    待加密的内容
     * @param encryptKey 加密密钥
     * @return 加密后的base 64 code
     * @throws Exception
     */
    public static String aesEncrypt(String content, String encryptKey) throws Exception {
        return base64Encode(aesEncryptToBytes(content, encryptKey));
    }

    /**
     * AES解密
     *
     * @param encryptBytes 待解密的byte[]
     * @param decryptKey   解密密钥
     * @return 解密后的String
     * @throws Exception
     */
    public static String aesDecryptByBytes(byte[] encryptBytes, String decryptKey) throws Exception {
        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        kgen.init(128, new SecureRandom(decryptKey.getBytes()));

        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(kgen.generateKey().getEncoded(), "AES"));
        byte[] decryptBytes = cipher.doFinal(encryptBytes);

        return new String(decryptBytes);
    }

    /**
     * 将base 64 code AES解密
     *
     * @param encryptStr 待解密的base 64 code
     * @param decryptKey 解密密钥
     * @return 解密后的string
     * @throws Exception
     */
    public static String aesDecrypt(String encryptStr, String decryptKey) throws Exception {
        return StringUtils.isEmpty(encryptStr) ? null : aesDecryptByBytes(base64Decode(encryptStr), decryptKey);
    }
}