工厂方法模式

目前常用的加密算法有DES（Data Encryption Standard）和IDEA（International Data Encryption Algorithm）国际数据加密算法等，请用工厂方法实现加密算法系统。

实验要求：

1.画出对应的类图；

2.提交该系统的代码，该系统务必是一个可以能够直接使用的系统，查阅资料完成相应加密算法的实现；

3.注意编程规范。

1.类图

 

2. 系统代码

package org.example;

public interface EncryptionAlgorithm {
    byte[] encrypt(byte[] data);
}

package org.example;

import java.util.Arrays;

public class DESAlgorithm implements EncryptionAlgorithm {
    @Override
    public byte[] encrypt(byte[] data) {
        // 实现DES加密逻辑
        return Arrays.copyOfRange(data, 0, data.length);
    }
}

package org.example;

import java.util.Arrays;

public class IDEAAlgorithm implements EncryptionAlgorithm {
    @Override
    public byte[] encrypt(byte[] data) {
        // 实现IDEA加密逻辑
        return Arrays.copyOfRange(data, 0, data.length);
    }
}

package org.example;

public class EncryptionAlgorithmFactory {
    public static EncryptionAlgorithm getEncryptionAlgorithm(String algorithmType) {
        if ("DES".equalsIgnoreCase(algorithmType)) {
            return new DESAlgorithm();
        } else if ("IDEA".equalsIgnoreCase(algorithmType)) {
            return new IDEAAlgorithm();
        } else {
            throw new IllegalArgumentException("Unsupported algorithm type: " + algorithmType);
        }
    }
}

package org.example;

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        String algorithmType = "DES"; // 或者 "IDEA"
        EncryptionAlgorithm encryptionAlgorithm = EncryptionAlgorithmFactory.getEncryptionAlgorithm(algorithmType);

        byte[] data = "Hello, World!".getBytes();
        byte[] encryptedData = encryptionAlgorithm.encrypt(data);

        System.out.println("Encrypted Data: " + Arrays.toString(encryptedData));

    }
}