编写java程序代码实现一个常见的加解密算法的可交互的程序

以下是一个使用Java实现常用加解密算法的可交互程序，包括AES、DES、RSA和MD5算法：

import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.math.*;
import java.util.*;

public class EncryptionProgram {

    public static void main(String[] args) throws Exception {

        Scanner sc = new Scanner(System.in);

        System.out.println("Welcome to the Encryption Program!\n");

        while (true) {

            System.out.println("Please choose an encryption algorithm:");
            System.out.println("1. AES");
            System.out.println("2. DES");
            System.out.println("3. RSA");
            System.out.println("4. MD5");
            System.out.println("5. Exit");

            int choice = sc.nextInt();

            switch (choice) {
                case 1:
                    aesEncryption();
                    break;
                case 2:
                    desEncryption();
                    break;
                case 3:
                    rsaEncryption();
                    break;
                case 4:
                    md5Encryption();
                    break;
                case 5:
                    System.out.println("Goodbye!");
                    sc.close();
                    System.exit(0);
                default:
                    System.out.println("Invalid choice!\n");
                    break;
            }
        }
    }

    public static void aesEncryption() throws Exception {

        Scanner sc = new Scanner(System.in);

        System.out.println("\nAES Encryption\n");

        System.out.print("Enter the message you want to encrypt: ");
        String message = sc.nextLine();

        System.out.print("Enter the secret key: ");
        String secretKey = sc.nextLine();

        KeyGenerator keyGen = KeyGenerator.getInstance("AES");
        SecureRandom random = new SecureRandom(secretKey.getBytes());
        keyGen.init(random);
        SecretKey key = keyGen.generateKey();

        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.ENCRYPT_MODE, key);
        byte[] encrypted = cipher.doFinal(message.getBytes());

        System.out.println("Encrypted message: " + new String(encrypted));
    }

    public static void desEncryption() throws Exception {

        Scanner sc = new Scanner(System.in);

        System.out.println("\nDES Encryption\n");

        System.out.print("Enter the message you want to encrypt: ");
        String message = sc.nextLine();

        System.out.print("Enter the secret key: ");
        String secretKey = sc.nextLine();

        DESKeySpec keySpec = new DESKeySpec(secretKey.getBytes());
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        SecretKey key = keyFactory.generateSecret(keySpec);

        Cipher cipher = Cipher.getInstance("DES");
        cipher.init(Cipher.ENCRYPT_MODE, key);
        byte[] encrypted = cipher.doFinal(message.getBytes());

        System.out.println("Encrypted message: " + new String(encrypted));
    }

    public static void rsaEncryption() throws Exception {

        Scanner sc = new Scanner(System.in);

        System.out.println("\nRSA Encryption\n");

        System.out.print("Enter the message you want to encrypt: ");
        String message = sc.nextLine();

        KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
        keyGen.initialize(1024);
        KeyPair keyPair = keyGen.generateKeyPair();
        PublicKey publicKey = keyPair.getPublic();

        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] encrypted = cipher.doFinal(message.getBytes());

        System.out.println("Encrypted message: " + new String(encrypted));
    }

    public static void md5Encryption() throws Exception {

        Scanner sc = new Scanner(System.in);

        System.out.println("\nMD5 Encryption\n");

        System.out.print("Enter the message you want to encrypt: ");
        String message = sc.nextLine();

        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] messageDigest = md.digest(message.getBytes());

        BigInteger no = new BigInteger(1, messageDigest);
        String hashtext = no.toString(16);

        while (hashtext.length() < 32) {
            hashtext = "0" + hashtext;
        }

        System.out.println("Encrypted message: " + hashtext);
    }
}

在这个程序中，用户可以选择要使用的加密算法，并输入要加密的消息和秘钥。然后程序将对消息执行加密，并输出加密后的结果。对于MD5算法，输出的是哈希值。

此程序仅用于演示目的，实际应用中需要进行更多的错误处理和异常处理。