Java 实现 AES 加密和解密完整示例

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.security.SecureRandom;
import java.util.Base64;
 
public class AESUtil {
 
    // AES密钥算法
    private static final String KEY_ALGORITHM = "AES";
 
    // 加密/解密算法/工作模式/填充方式
    private static final String CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";
 
    // 生成密钥
    public static String generateAESKey() throws Exception {
        KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_ALGORITHM);
        keyGenerator.init(128, new SecureRandom()); // 192 and 256 bits may not be available
        SecretKey secretKey = keyGenerator.generateKey();
        return Base64.getEncoder().encodeToString(secretKey.getEncoded());
    }
 
    // AES加密
    public static String encryptAES(String data, String key) throws Exception {
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        SecretKeySpec secretKeySpec = new SecretKeySpec(Base64.getDecoder().decode(key), KEY_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
        byte[] encrypted = cipher.doFinal(data.getBytes());
        return Base64.getEncoder().encodeToString(encrypted);
    }
 
    // AES解密
    public static String decryptAES(String data, String key) throws Exception {
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        SecretKeySpec secretKeySpec = new SecretKeySpec(Base64.getDecoder().decode(key), KEY_ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
        byte[] decrypted = cipher.doFinal(Base64.getDecoder().decode(data));
        return new String(decrypted);
    }
 
    public static void main(String[] args) {
        try {
            String key = generateAESKey();
            String originalText = "Hello World!";
            String encryptedText = encryptAES(originalText, key);
            String decryptedText = decryptAES(encryptedText, key);
 
            System.out.println("Original Text : " + originalText);
            System.out.println("Encrypted Text : " + encryptedText);
            System.out.println("Decrypted Text : " + decryptedText);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

这段代码提供了AES加密和解密的基本操作，包括密钥的生成、加密和解密。在main方法中，我们生成了一个密钥，用这个密钥对字符串"Hello Wo