Java加密信息——设计模式工厂方法模式

package Test;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import java.util.Base64;
import java.util.Scanner;
import java.nio.charset.StandardCharsets;

// 工厂方法接口
interface EncryptionAlgorithmFactory {
    Cipher createCipher();
}

// 具体工厂类 - DES算法工厂
class DESAlgorithmFactory implements EncryptionAlgorithmFactory {
    @Override
    public Cipher createCipher() {
        try {
            return Cipher.getInstance("DES");
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

// 具体工厂类 - IDEA算法工厂
class IDEAAlgorithmFactory implements EncryptionAlgorithmFactory {
    @Override
    public Cipher createCipher() {
        try {
            return Cipher.getInstance("AES");
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

public class test1 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("请选择加密方法 (DES 或 IDEA):");
        String algorithmType = scanner.nextLine();

        // 使用工厂方法根据用户选择创建加密算法
        EncryptionAlgorithmFactory algorithmFactory;
        if ("DES".equalsIgnoreCase(algorithmType)) {
            algorithmFactory = new DESAlgorithmFactory();
        } else if ("IDEA".equalsIgnoreCase(algorithmType)) {
            algorithmType="AES";
            algorithmFactory = new IDEAAlgorithmFactory();
        } else {
            System.out.println("不支持此种加密方法！");
            return;
        }

        try {
            Cipher cipher = algorithmFactory.createCipher();

            System.out.println("请输入要加密的内容:");
            String dataToEncrypt = scanner.nextLine();

            // 生成随机密钥
            KeyGenerator keyGenerator = KeyGenerator.getInstance(algorithmType);
            SecretKey secretKey = keyGenerator.generateKey();

            // 初始化加密模式
            cipher.init(Cipher.ENCRYPT_MODE, secretKey);

            // 加密数据
            byte[] encryptedData = cipher.doFinal(dataToEncrypt.getBytes(StandardCharsets.UTF_8));
            String encryptedDataString = Base64.getEncoder().encodeToString(encryptedData);

            System.out.println("初始数据: " + dataToEncrypt);
            System.out.println("加密后数据: " + encryptedDataString);

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            scanner.close();
        }
    }
}