android AES加密工具類

    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, skeySpec, 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));  

    }  

}  </pre>