加解密工具

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import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.SecureRandom;
import java.util.Base64;


public class EnDeCryptUtil {

    private final static String DES = "DES";

    /**
     * 根据键值进行加密
     * @param data
     * @param key  加密键byte数组
     * @return
     * @throws Exception
     */
    public static String encrypt(String data, String key, int size) throws Exception {
        byte[] bt = encrypt(data.getBytes("UTF-8"), key.getBytes(), size);
        String strs = Base64.getEncoder().encodeToString(bt);
        return strs;
    }

    /**
     * 根据键值进行解密
     * @param data
     * @param key  加密键byte数组
     * @return
     * @throws IOException
     * @throws Exception
     */
    public static String decrypt(String data, String key, int size) throws IOException,
            Exception {
        if (data == null)
            return null;
        byte[] buf = Base64.getDecoder().decode(data.replace("\r\n", ""));
        byte[] bt = decrypt(buf,key.getBytes(),size);
        return new String(new String(bt).getBytes(),"UTF-8");
    }

    /**
     * 根据键值进行加密
     * @param data
     * @param key  加密键byte数组
     * @return
     * @throws Exception
     */
    private static byte[] encrypt(byte[] data, byte[] key, int size) throws Exception {
        // 生成一个可信任的随机数源
        SecureRandom sr = new SecureRandom();

        // 从原始密钥数据创建DESKeySpec对象
        DESKeySpec dks = new DESKeySpec(key,size);

        // 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
        SecretKey securekey = keyFactory.generateSecret(dks);

        // Cipher对象实际完成加密操作
        Cipher cipher = Cipher.getInstance(DES);

        // 用密钥初始化Cipher对象
        cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);

        return cipher.doFinal(data);
    }


    /**
     * 根据键值进行解密
     * @param data
     * @param key  加密键byte数组
     * @return
     * @throws Exception
     */
    private static byte[] decrypt(byte[] data, byte[] key, int size) throws Exception {
        // 生成一个可信任的随机数源
        SecureRandom sr = new SecureRandom();

        // 从原始密钥数据创建DESKeySpec对象
        DESKeySpec dks = new DESKeySpec(key,size);

        // 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
        SecretKey securekey = keyFactory.generateSecret(dks);

        // Cipher对象实际完成解密操作
        Cipher cipher = Cipher.getInstance(DES);

        // 用密钥初始化Cipher对象
        cipher.init(Cipher.DECRYPT_MODE, securekey, sr);

        return cipher.doFinal(data);
    }


    /**
     * MD5 32位加密
     *
     * @param encryptStr
     * @return String
     */
    public static String encrypt32(String encryptStr) {
        char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

        try {
            byte[] btInput = encryptStr.getBytes();
            // 获得MD5摘要算法的 MessageDigest 对象
            MessageDigest mdInst = MessageDigest.getInstance("MD5");
            // 使用指定的字节更新摘要
            mdInst.update(btInput);
            // 获得密文
            byte[] md = mdInst.digest();
            // 把密文转换成十六进制的字符串形式
            int j = md.length;
            char str[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte byte0 = md[i];
                str[k++] = hexDigits[byte0 >>> 4 & 0xf];
                str[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(str).toUpperCase();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }


    public static void main(String[] args) throws Exception {
        String data = "{test:\"test\",Sys:\"01\",Name:\"压缩\",sex:\"boy\",tel:\"13800138000\",Desc:\"哈塞给\"}";
        String key = "secret1234";//秘钥 必须8位以上
        System.out.println(key.getBytes().length);
        String encode = encrypt(data, key, 0);
        System.out.println(encode);
        String dcode = decrypt(encode, key, 0);
        System.out.println(dcode);
    }
}