要实现AES加密的C#和Java之间的互通，可以使用以下步骤：

1. 在C#中进行AES加密：

using System;
using System.Security.Cryptography;
using System.Text;

public class AesEncryption
{
    public static string Encrypt(string plainText, string key, string iv)
    {
        using (Aes aesAlg = Aes.Create())
        {
            aesAlg.Key = Encoding.UTF8.GetBytes(key);
            aesAlg.IV = Encoding.UTF8.GetBytes(iv);

            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

            byte[] encryptedData;
            using (var msEncrypt = new System.IO.MemoryStream())
            {
                using (var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (var swEncrypt = new System.IO.StreamWriter(csEncrypt))
                    {
                        swEncrypt.Write(plainText);
                    }
                    encryptedData = msEncrypt.ToArray();
                }
            }

            return Convert.ToBase64String(encryptedData);
        }
    }
}

2. 在Java中进行AES解密：

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AesDecryption {
    public static String Decrypt(String encryptedText, String key, String iv) throws Exception {
        byte[] encryptedData = Base64.getDecoder().decode(encryptedText);
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

        SecretKeySpec secretKeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
        IvParameterSpec ivParameterSpec = new IvParameterSpec(iv.getBytes("UTF-8"));

        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);

        byte[] decryptedData = cipher.doFinal(encryptedData);

        return new String(decryptedData);
    }
}

3. 调用C#的AES加密方法，并使用Java的AES解密方法解密：

string plainText = "Hello World";
string key = "0123456789ABCDEF";
string iv = "FEDCBA9876543210";

string encryptedText = AesEncryption.Encrypt(plainText, key, iv);
System.out.println("Encrypted Text: " + encryptedText);

String decryptedText = AesDecryption.Decrypt(encryptedText, key, iv);
System.out.println("Decrypted Text: " + decryptedText);

这样，你就可以在C#和Java之间实现AES加密和解密的互通了。请注意，确保C#和Java中使用的密钥和初始向量（IV）相同，以便正确解密数据。