Java实现AES简要代码包括生成随机密钥

以下是Java实现AES加密和解密并生成随机密钥的简要代码：

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class AESUtil {
    
    private static final String KEY_ALGORITHM = "AES";
    private static final String CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";
    
    /**
     * 生成随机密钥
     *
     * @return 密钥
     */
    public static String generateKey() throws Exception {
        KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_ALGORITHM);
        keyGenerator.init(128);
        SecretKey secretKey = keyGenerator.generateKey();
        byte[] encoded = secretKey.getEncoded();
        return Base64.getEncoder().encodeToString(encoded);
    }
    
    /**
     * AES加密
     *
     * @param content 需要加密的字符串
     * @param key     密钥
     * @return 加密后的字符串
     */
    public static String encrypt(String content, 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(content.getBytes(StandardCharsets.UTF_8));
        return Base64.getEncoder().encodeToString(encrypted);
    }
    
    /**
     * AES解密
     *
     * @param content 需要解密的字符串
     * @param key     密钥
     * @return 解密后的字符串
     */
    public static String decrypt(String content, 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(content));
        return new String(decrypted, StandardCharsets.UTF_8);
    }
}

使用示例：

public class Test {
    
    public static void main(String[] args) throws Exception {
        String content = "Hello, world!";
        
        // 生成随机密钥
        String key = AESUtil.generateKey();
        System.out.println("生成的密钥：" + key);
        
        // 加密
        String encrypted = AESUtil.encrypt(content, key);
        System.out.println("加密后的字符串：" + encrypted);

        // 解密
        String decrypted = AESUtil.decrypt(encrypted, key);
        System.out.println("解密后的字符串：" + decrypted);
    }
}