如何将secretKey和IV存储在一个文件中，以便使用Java进行加密和解密？

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class EncryptionExample {
    public static void main(String[] args) {
        String secretKey = "";
        String iv = "";

        try {
            // 读取存储secretKey和IV的文件
            BufferedReader reader = new BufferedReader(new FileReader("keys.txt"));
            String line;
            while ((line = reader.readLine()) != null) {
                String[] parts = line.split("=");
                if (parts.length == 2) {
                    if (parts[0].trim().equals("secretKey")) {
                        secretKey = parts[1].trim();
                    } else if (parts[0].trim().equals("IV")) {
                        iv = parts[1].trim();
                    }
                }
            }
            reader.close();

            // 加密
            String plaintext = "Hello, World!";
            String ciphertext = encrypt(plaintext, secretKey, iv);
            System.out.println("Encrypted: " + ciphertext);

            // 解密
            String decryptedText = decrypt(ciphertext, secretKey, iv);
            System.out.println("Decrypted: " + decryptedText);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static String encrypt(String plaintext, String secretKey, String iv) {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            SecretKeySpec keySpec = new SecretKeySpec(secretKey.getBytes(StandardCharsets.UTF_8), "AES");
            IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes(StandardCharsets.UTF_8));
            cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
            byte[] encrypted = cipher.doFinal(plaintext.getBytes(StandardCharsets.UTF_8));
            return Base64.getEncoder().encodeToString(encrypted);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    public static String decrypt(String ciphertext, String secretKey, String iv) {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            SecretKeySpec keySpec = new SecretKeySpec(secretKey.getBytes(StandardCharsets.UTF_8), "AES");
            IvParameterSpec ivSpec = new IvParameterSpec(iv.getBytes(StandardCharsets.UTF_8));
            cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
            byte[] decrypted = cipher.doFinal(Base64.getDecoder().decode(ciphertext));
            return new String(decrypted, StandardCharsets.UTF_8);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}