import javax.crypto.Cipher;  
import javax.crypto.spec.IvParameterSpec;  
import javax.crypto.spec.SecretKeySpec;  
import java.nio.charset.StandardCharsets;  
import java.util.Base64;  
  
public class WeChatPhoneNumberDecrypter {  
  
    private static final String ALGORITHM = "AES/CBC/PKCS5Padding";  
  
    public static String decryptPhoneNumber(String encryptedData, String sessionKey, String iv) throws Exception {  
        // Base64 解碼  
        byte[] encryptedDataBytes = Base64.getDecoder().decode(encryptedData);  
        byte[] sessionKeyBytes = Base64.getDecoder().decode(sessionKey);  
        byte[] ivBytes = Base64.getDecoder().decode(iv);  
  
        // 設(shè)置AES密鑰和初始化向量  
        SecretKeySpec secretKeySpec = new SecretKeySpec(sessionKeyBytes, "AES");  
        IvParameterSpec ivParameterSpec = new IvParameterSpec(ivBytes);  
  
        // 創(chuàng)建Cipher實(shí)例并初始化  
        Cipher cipher = Cipher.getInstance(ALGORITHM);  
        cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);  
  
        // 解密  
        byte[] decryptedBytes = cipher.doFinal(encryptedDataBytes);  
  
        // 將解密后的字節(jié)轉(zhuǎn)換為字符串  
        return new String(decryptedBytes, StandardCharsets.UTF_8);  
    }  
  
    public static void main(String[] args) {  
        try {  
            // 這些值通常從微信小程序前端獲取，并通過(guò)網(wǎng)絡(luò)請(qǐng)求發(fā)送到后端  
            String encryptedData = "..."; // 加密的手機(jī)號(hào)數(shù)據(jù)，從微信小程序獲取  
            String sessionKey = "..."; // 會(huì)話密鑰，從微信小程序獲取  
            String iv = "..."; // 初始化向量，從微信小程序獲取  
  
            // 解密手機(jī)號(hào)  
            String decryptedPhoneNumber = decryptPhoneNumber(encryptedData, sessionKey, iv);  
            System.out.println("解密后的手機(jī)號(hào): " + decryptedPhoneNumber);  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
    }  
}