用Java加密字符串

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

public class StringEncryptionExample {
    public static void main(String[] args) throws Exception {
        String plaintext = "Hello, World!";
        String password = "MySecretPassword";

        byte[] encryptedText = encrypt(plaintext, password);
        System.out.println("Encrypted Text: " + new String(encryptedText, StandardCharsets.UTF_8));

        String decryptedText = decrypt(encryptedText, password);
        System.out.println("Decrypted Text: " + decryptedText);
    }

    public static byte[] encrypt(String plaintext, String password) throws Exception {
        SecretKeySpec secretKey = generateSecretKey(password);
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        return cipher.doFinal(plaintext.getBytes(StandardCharsets.UTF_8));
    }

    public static String decrypt(byte[] encryptedText, String password) throws Exception {
        SecretKeySpec secretKey = generateSecretKey(password);
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        byte[] decryptedBytes = cipher.doFinal(encryptedText);
        return new String(decryptedBytes, StandardCharsets.UTF_8);
    }

    private static SecretKeySpec generateSecretKey(String password) throws NoSuchAlgorithmException {
        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
        SecureRandom secureRandom = new SecureRandom(password.getBytes(StandardCharsets.UTF_8));
        keyGenerator.init(256, secureRandom);
        SecretKey secretKey = keyGenerator.generateKey();
        return new SecretKeySpec(secretKey.getEncoded(), "AES");
    }
}