AES加密算法java代码

AES（Advanced Encryption Standard）是一种高级加密标准，用于对数据进行块级加密。Java中使用`javax.crypto.Cipher`类和`javax.crypto.spec.SecretKeySpec`来实现AES加密。以下是一个简单的AES加解密示例：

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.security.Key;

public class AESExample {
    private static final String ALGORITHM = "AES";
    private static final byte[] keyValue = "YourSecretKey1234567890".getBytes(); // 用你的密钥替换

    public static String encrypt(String value) throws Exception {
        Key secretKey = generateSecretKey();
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        byte[] encryptedValue = cipher.doFinal(value.getBytes());
        return bytesToHex(encryptedValue);
    }

    public static String decrypt(String encryptedValue) throws Exception {
        Key secretKey = generateSecretKey();
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        byte[] decryptedValue = cipher.doFinal(hexToBytes(encryptedValue));
        return new String(decryptedValue);
    }

    private static Key generateSecretKey() throws Exception {
        SecretKeySpec secretKeySpec = new SecretKeySpec(keyValue, ALGORITHM);
        return secretKeySpec;
    }

    private static byte[] bytesToHex(byte[] bytes) {
        StringBuilder result = new StringBuilder();
        for (byte b : bytes) {
            result.append(String.format("%02x", b));
        }
        return result.toString().getBytes();
    }

    private static byte[] hexToBytes(String hexString) {
        int len = hexString.length();
        byte[] data = new byte[len / 2];
        for (int i = 0; i < len; i += 2) {
            data[i / 2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4)
                    + Character.digit(hexString.charAt(i+1), 16));
        }
        return data;
    }
}

在这个例子中，你需要提供一个密钥字符串（替换`"YourSecretKey1234567890"`），`encrypt`方法用于加密，`decrypt`方法用于解密。