android AES加密工具类

    import android.annotation.SuppressLint;  
    import java.security.SecureRandom;  
      
    import javax.crypto.Cipher;  
    import javax.crypto.KeyGenerator;  
    import javax.crypto.SecretKey;  
    import javax.crypto.spec.IvParameterSpec;  
    import javax.crypto.spec.SecretKeySpec;  
      
    /** 
     *  
     *  
     * Author：sunger 
     */  
    public class AESUtils {  
      
        public static String encrypt(String seed,String cleartext)  
                throws Exception {  
      
            byte[] rawKey = getRawKey(seed.getBytes());  
      
            byte[] result = encrypt(rawKey,cleartext.getBytes());  
      
            return toHex(result);  
      
        }  
      
        public static String decrypt(String seed,String encrypted)  
                throws Exception {  
      
            byte[] rawKey = getRawKey(seed.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");  
      
            SecureRandom sr = SecureRandom.getInstance("SHA1PRNG","Crypto");  
      
            sr.setSeed(seed);  
      
            kgen.init(128,sr); // 192 and 256 bits may not be available  
      
            SecretKey skey = kgen.generateKey();  
      
            byte[] raw = skey.getEncoded();  
      
            return raw;  
      
        }  
      
        private static byte[] encrypt(byte[] raw,byte[] clear) throws Exception {  
      
            SecretKeySpec skeySpec = new SecretKeySpec(raw,"AES");  
      
            Cipher cipher = Cipher.getInstance("AES");  
      
            cipher.init(Cipher.ENCRYPT_MODE,skeySpec,new IvParameterSpec(  
                    new byte[cipher.getBlockSize()]));  
      
            byte[] encrypted = cipher.doFinal(clear);  
      
            return encrypted;  
      
        }  
      
        private static byte[] decrypt(byte[] raw,byte[] encrypted)  
                throws Exception {  
      
            SecretKeySpec skeySpec = new SecretKeySpec(raw,"AES");  
      
            Cipher cipher = Cipher.getInstance("AES");  
      
            cipher.init(Cipher.DECRYPT_MODE,new IvParameterSpec(  
                    new byte[cipher.getBlockSize()]));  
      
            byte[] decrypted = cipher.doFinal(encrypted);  
      
            return decrypted;  
      
        }  
      
        private 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;  
      
        }  
      
        private 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));  
      
        }  
      
    }