如何使用BouncyCastle使用AES-GCM加密CMSGCM值？

import org.bouncycastle.jce.provider.BouncyCastleProvider;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import java.security.Security;

// 添加BouncyCastle作为安全提供者
Security.addProvider(new BouncyCastleProvider());

// 生成AES-GCM密钥
KeyGenerator keyGenerator = KeyGenerator.getInstance("AES", "BC");
keyGenerator.init(256); // 设置密钥长度为256位
SecretKey secretKey = keyGenerator.generateKey();

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;

// 加密数据
byte[] plaintext = "要加密的数据".getBytes("UTF-8");
byte[] nonce = "12字节的随机数".getBytes("UTF-8");

Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding", "BC");
SecretKey secretKey = new SecretKeySpec(secretKey.getEncoded(), "AES");
GCMParameterSpec gcmParameterSpec = new GCMParameterSpec(128, nonce);
cipher.init(Cipher.ENCRYPT_MODE, secretKey, gcmParameterSpec);
byte[] ciphertext = cipher.doFinal(plaintext);

// 解密数据
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding", "BC");
cipher.init(Cipher.DECRYPT_MODE, secretKey, gcmParameterSpec);
byte[] decryptedText = cipher.doFinal(ciphertext);
String plaintext = new String(decryptedText, "UTF-8");