JAVA AES CBC解密，用0填充

如果你需要使用Java进行AES CBC解密，并且需要使用0填充，可以使用以下代码：

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AESCBCDecrypt {

    public static void main(String[] args) throws Exception {
        
        byte[] key = "0123456789abcdef".getBytes("UTF-8");
        byte[] iv = "0123456789abcdef".getBytes("UTF-8");
        byte[] encrypted = hexStringToByteArray("7f5d8d9dceb05d9a4a9d2a8a9e8c2c9b");

        // Create the key specification and the initialization vector specification
        SecretKeySpec keySpec = new SecretKeySpec(key, "AES");
        IvParameterSpec ivSpec = new IvParameterSpec(iv);

        // Create the cipher object and initialize it with the key and initialization vector
        Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);

        // Decrypt the ciphertext
        byte[] decrypted = cipher.doFinal(encrypted);

        // Print the decrypted plaintext
        System.out.println(new String(decrypted, "UTF-8"));
    }

    // Helper function to convert a hex string to a byte array
    public static byte[] hexStringToByteArray(String s) {
        int len = s.length();
        byte[] data = new byte[len / 2];
        for (int i = 0; i < len; i += 2) {
            data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
                                 + Character.digit(s.charAt(i+1), 16));
        }
        return data;
    }
}

在上面的代码中，我们使用AES/CBC/NoPadding模式进行解密，这意味着我们需要手动添加填充。在这种情况下，我们使用0字节作为填充字符。