import android.annotation.SuppressLint;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;


public class AESEncryptor {
    public static String key = "abcdefg";
    public static String encrypt(String src) throws Exception {
        byte[] rawKey = getRawKey(key.getBytes());
        byte[] result = encrypt(rawKey, src.getBytes());
        return toHex(result);
    }
    public static String decrypt(String encrypted) throws Exception {
        byte[] rawKey = getRawKey(key.getBytes());
        byte[] enc = toByte(encrypted);
        byte[] result = decrypt(rawKey, enc);
        return new String(result);
    }
    @SuppressLint("TrulyRandom")
    private static byte[] getRawKey(byte[] seed) throws Exception {
        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        // SHA1PRNG 强随机种子算法, 要区别4.2以上版本的调用方法
        SecureRandom sr = null;
        if (android.os.Build.VERSION.SDK_INT > android.os.Build.VERSION_CODES.JELLY_BEAN) {
            sr = SecureRandom.getInstance("SHA1PRNG", "Crypto");
        } else {
            sr = SecureRandom.getInstance("SHA1PRNG");
        }
        sr.setSeed(seed);
        kgen.init(256, sr); // 256 bits or 128 bits,192bits
        SecretKey skey = kgen.generateKey();
        byte[] raw = skey.getEncoded();
        return raw;
    }

    private static byte[] encrypt(byte[] key, byte[] src) throws Exception {
        SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
        byte[] encrypted = cipher.doFinal(src);
        return encrypted;
    }
    private static byte[] decrypt(byte[] key, byte[] encrypted)
            throws Exception {
        SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.DECRYPT_MODE, skeySpec);
        byte[] decrypted = cipher.doFinal(encrypted);
        return decrypted;
    }
    public static String toHex(String txt) {
        return toHex(txt.getBytes());
    }
    public static String fromHex(String hex) {
        return new String(toByte(hex));
    }
    public static byte[] toByte(String hexString) {
        int len = hexString.length() / 2;
        byte[] result = new byte[len];
        for (int i = 0; i < len; i++)
            result[i] = Integer.valueOf(
                    hexString.substring(2 * i, 2 * i + 2), 16).byteValue();
        return result;
    }
    public static String toHex(byte[] buf) {
        if (buf == null)
            return "";
        StringBuffer result = new StringBuffer(2 * buf.length);
        for (int i = 0; i < buf.length; i++) {
            appendHex(result, buf[i]);
        }
        return result.toString();
    }
    private final static String HEX = "0123456789ABCDEF";
    private static void appendHex(StringBuffer sb, byte b) {
        sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f));
    }
}

更多相关文章

  1. 分享一个两个Android(安卓)scrollView同时滚动的方法
  2. Android(安卓)内验证Https证书问题
  3. Android(安卓)调用.NET webservice
  4. Android(安卓)浏览网页
  5. Android(安卓)浅析 ContentProvider (一) 使用
  6. android:Service
  7. android调用键盘
  8. Android重写view时onAttachedToWindow
  9. android调用本地录制程序获取录制文件路径的问题

随机推荐

  1. Android截屏及图片解析
  2. Linux 下进行Android开发环境搭建
  3. Android(安卓)中支持的几种传感器
  4. 实例教程四:采用Pull解析器解析和生成XML
  5. a64_7.1android平板关于更改绘制矩形界面
  6. android中去掉空格--trim函数
  7. Android避免启动时闪一下黑屏
  8. Android中获得SD卡中的值
  9. Android-AlarmManager(全局定时器/闹钟)
  10. ToolBar的使用