구성 파일에서 비밀번호를 안전하게 암호화하는 방법: 키는 어떻습니까?

import java.security.AlgorithmParameters;
import java.security.GeneralSecurityException;
import java.security.spec.IvParameterSpec;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;

public class SecureConfigFile {
    // Encrypt the original password using a password-protected key
    private static String encrypt(String originalPassword, SecretKeySpec key) {
        ...
    }

    // Decrypt the encrypted password using the same password-protected key
    private static String decrypt(String encryptedPassword, SecretKeySpec key) {
        ...
    }

    // Create a password-protected key using PBKDF2WithHmacSHA512
    private static SecretKeySpec createSecretKey(char[] password, byte[] salt) {
        ...
    }
}