AES加密需要：明文 + 密钥+ 偏移量（IV）+密码模式(算法/模式/填充)AES解密需要：密文 + 密钥+ 偏移量（IV）+密码模式(算法/模式/填充)
其中加密和解密的密钥，偏移量和密码模式要相同。实际工作中，对加密结果做Base64转换，在解密之前要做Base64逆转换。上代码： import android.text.TextUtils; import android.util.Base64; import java.security.Provider; import java.security.SecureRandom; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; public class AESUtil { private final static String HEX = "0123456789ABCDEF"; private static final String CBC_PKCS5_PADDING = "AES/CBC/PKCS5Padding";//AES是加密方式 CBC是工作模式 PKCS5Padding是填充模式 private static final String AES = "AES";//AES 加密 private static final String SHA1PRNG = "SHA1PRNG";// SHA1PRNG 强随机种子算法, 要区别4.2以上版本的调用方法 /* *生成密钥，加密和解密的密钥必须一致，不然将不能解密 */ public static String generateKey() { try { SecureRandom secureRandom = SecureRandom.getInstance(SHA1PRNG); byte[] key = new byte[20]; secureRandom.nextBytes(key); return toHex(key); } catch (Exception e) { e.printStackTrace(); } return null; } // 对密钥进行处理 private static byte[] getRawKey(byte[] seed) throws Exception { KeyGenerator keyGenerator = KeyGenerator.getInstance(AES); SecureRandom sr = null; // 在4.2以上版本中，SecureRandom获取方式发生了改变 if (android.os.Build.VERSION.SDK_INT >= 17) { sr = SecureRandom.getInstance(SHA1PRNG, new CryptoProvider()); } else { sr = SecureRandom.getInstance(SHA1PRNG); } sr.setSeed(seed); keyGenerator.init(128, sr);//256 bits or 128 bits,192bits //AES中128位密钥版本有10个加密循环，192比特密钥版本有12个加密循环，256比特密钥 // 版本则有14个加密循环。 return keyGenerator.generateKey().getEncoded(); } /** * 加密 * * @param key 密钥 * @param plaintext 明文 * @return */ public static String encrypt(String key, String plaintext) { if (TextUtils.isEmpty(plaintext)) { return plaintext; } try { byte[] result = encrypt(key, plaintext.getBytes("UTF-8")); return new String(Base64.encode(result, Base64.DEFAULT)); } catch (Exception e) { e.printStackTrace(); } return null; } /** * 加密 * * @param key * @param ciphertext * @return * @throws Exception */ private static byte[] encrypt(String key, byte[] ciphertext) throws Exception { byte[] raw = getRawKey(key.getBytes()); SecretKeySpec secretKeySpec = new SecretKeySpec(raw, AES); Cipher cipher = Cipher.getInstance(CBC_PKCS5_PADDING); cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, new IvParameterSpec(new byte[cipher.getBlockSize()])); return cipher.doFinal(ciphertext); } /** * 二进制转字符 * * @param buf * @return */ 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 static void appendHex(StringBuffer sb, byte b) { sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f)); } /** * 解密 * * @param key 密钥 * @param ciphertext 密文 * @return */ public static String decrypt(String key, String ciphertext) { if (TextUtils.isEmpty(ciphertext)) { return ciphertext; } try { byte[] enc = Base64.decode(ciphertext.getBytes("UTF-8"), Base64.DEFAULT); byte[] result = decrypt(key, enc); return new String(result); } catch (Exception e) { e.printStackTrace(); } return null; } /** * 真正解密 * * @param key 密钥 * @param ciphertext 密文 * @return */ private static byte[] decrypt(String key, byte[] ciphertext) { try { byte[] raw = getRawKey(key.getBytes()); SecretKeySpec secretKeySpec = new SecretKeySpec(raw, AES); Cipher cipher = Cipher.getInstance(CBC_PKCS5_PADDING); cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, new IvParameterSpec(new byte[cipher.getBlockSize()])); return cipher.doFinal(ciphertext); } catch (Exception e) { e.printStackTrace(); } return null; } static final class CryptoProvider extends Provider { /** * Creates a Provider and puts parameters */ public CryptoProvider() { super("Crypto", 1.0, "HARMONY (SHA1 digest; SecureRandom; SHA1withDSA signature)"); put("SecureRandom.SHA1PRNG", "org.apache.harmony.security.provider.crypto.SHA1PRNG_SecureRandomImpl"); put("SecureRandom.SHA1PRNG ImplementedIn", "Software"); } } } public class TestActivity extends Activity { @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); String key = AESUtil.generateKey(); Log.e("TestActivity", "key " + key); String content = AESUtil.encrypt(key, "测试AES OK!"); Log.e("TestActivity", "加密后 " + content); String ss = AESUtil.decrypt(key, content); Log.e("TestActivity", "解密后 " + ss); } } }