Question

帮帮我，我无法解密工作？这个程序已经获得加密而不是解密如何解决这个问题？

import javax.crypto.*;
import java.util.Scanner;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;

public class CIBAw
{    
    public static void main(String[] argv)  
    {
        Scanner input = new Scanner(System.in);
        Scanner File = new Scanner(System.in); 
        try
        {
            KeyGenerator keygenerator = KeyGenerator.getInstance("DES");
            SecretKey myDesKey = keygenerator.generateKey();
            Cipher desCipher;
            desCipher = Cipher.getInstance("DES");
            desCipher.init(Cipher.ENCRYPT_MODE, myDesKey);
            System.out.println("Encrypt a File");
            System.out.print("Enter a sentence:"); 
            //String file = File.nextLine(); 
            byte[] text = "".getBytes();
            System.out.println("" + new String(text));
            // Encrypt the text
            byte[] textEncrypted = desCipher.doFinal(text);
            System.out.println("File Encryted : " + textEncrypted);
            // Initialize the same cipher for decryption
            desCipher.init(Cipher.DECRYPT_MODE, myDesKey);
            // Decrypt the text
            byte[] textDecrypted = desCipher.doFinal(textEncrypted);
            System.out.println("File Decryted : " +  new String(textDecrypted));

        }catch(NoSuchAlgorithmException e)
        {
            e.printStackTrace();
        }catch(NoSuchPaddingException e)
        {
            e.printStackTrace();
        }catch(InvalidKeyException e)
        {
            e.printStackTrace();
        }catch(IllegalBlockSizeException e)
        {
            e.printStackTrace();
        }catch(BadPaddingException e)
        {
            e.printStackTrace();
        } 

    }
}

Answer 1

好看了之后，我改变了代码，使其更具可读性，并为您提供更好的技巧来解决这个问题：

阅读输入。
创建密钥实例（公共/私有）。
将输入转换为字节。
加密输入并将其打印出来。

解密输入并将其打印出来。

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    try
    {

        //Prompt for String
        System.out.print("Enter a sentence:");
        String in = input.next();

        //Generate Key for encryption/decryption
        KeyGenerator keygenerator = KeyGenerator.getInstance("DES");
        SecretKey myDesKey = keygenerator.generateKey();
        Cipher desCipher;
        desCipher = Cipher.getInstance("DES");
        desCipher.init(Cipher.ENCRYPT_MODE, myDesKey);

        //Cast the input into bytes 
        byte[] text = in.getBytes();
        System.out.println("" + new String(text));
        // Encrypt the text
        byte[] textEncrypted = desCipher.doFinal(text);
        System.out.println("File Encryted : " + textEncrypted);
        // Initialize the same cipher for decryption
        desCipher.init(Cipher.DECRYPT_MODE, myDesKey);
        // Decrypt the text
        byte[] textDecrypted = desCipher.doFinal(textEncrypted);
        System.out.println("File Decryted : " +  new String(textDecrypted));

    }catch(NoSuchAlgorithmException e)
    {
        e.printStackTrace();
    }catch(NoSuchPaddingException e)
    {
        e.printStackTrace();
    }catch(InvalidKeyException e)
    {
        e.printStackTrace();
    }catch(IllegalBlockSizeException e)
    {
        e.printStackTrace();
    }catch(BadPaddingException e)
    {
        e.printStackTrace();
    } 

}

Java加密/解密

1 个答案: