Question

抱歉，如果我的问题很愚蠢，但我正在学习java，我正在开展一个需要加密和解密的项目我完成了代码并且加密按钮功能齐全但是当我尝试解密（不同的按钮）时，始终存在错误。

加密代码

 path = chooser.getSelectedFile();
             String x = path.toString();

             try {

                Scanner scanner = new Scanner(new File(x));
                content = scanner.useDelimiter("\\Z").next();

            } catch (FileNotFoundException e2) {
                e2.printStackTrace();
            }

                try{

                    KeyGenerator keygenerator = KeyGenerator.getInstance("DES");
                    SecretKey myDesKey = keygenerator.generateKey();

                    Cipher desCipher;
                    desCipher = Cipher.getInstance("DES");


                    byte[] text = content.getBytes("UTF8");


                    desCipher.init(Cipher.ENCRYPT_MODE, myDesKey);
                    byte[] textEncrypted = desCipher.doFinal(text);

                    String s = new String(textEncrypted);

                    try {

                         File statText = new File(x);
                         FileOutputStream is = new FileOutputStream(statText);

                         OutputStreamWriter osw = new OutputStreamWriter(is);  

                         Writer w = new BufferedWriter(osw);
                         w.write(s);
                         w.close();
                        } 
                 catch (IOException e3) {
                     JOptionPane.showMessageDialog(null, "something is wrong with the txt file");
                                    }                      
                }catch(Exception e1)
                {
                    System.out.println("En");
                }

这里是解密部分：

 path = chooser.getSelectedFile();
             String x = path.toString();

             try {

                 Scanner scanner = new Scanner(new File(x));
                content = scanner.useDelimiter("\\Z").next();

            } catch (FileNotFoundException e2) {
                e2.printStackTrace();
            }

             try{
                    KeyGenerator keygenerator = KeyGenerator.getInstance("DES");
                    SecretKey myDesKey = keygenerator.generateKey();

                    Cipher desCipher;
                    desCipher = Cipher.getInstance("DES");


                    byte[] text = content.getBytes("UTF8");
                    byte[] textEncrypted = desCipher.doFinal(text);


                    desCipher.init(Cipher.DECRYPT_MODE, myDesKey);
                    byte[] textDecrypted = desCipher.doFinal(textEncrypted);

                    String s = new String(textDecrypted);
                    System.out.println(s);


                }catch(Exception e1)
                {
                    System.out.println("De"); /* here we go this is my error*/
                }

第二个代码的错误＆＃34; catch（例外e1）＆＃34;

Answer 1

我在你的代码中看到两个问题。在您的第一部分中，您只发送了加密消息，接收方不会解密，因为您没有将密钥发送到接收方。第二个问题是你使用String s = new String(textEncrypted);，你应该发送textEncrypted而不是字符串，因为将字节转换为字符串可能会因编码而丢失一些信息。

在第二部分中，您应该在加密前致电desCipher.init(Cipher.ENCRYPT_MODE, myDesKey);。

Answer 2

问题解决了

加密代码：

 path = chooser.getSelectedFile();
             String x = path.toString();

             try {
                 scanner = new Scanner(new File(x));
                content = scanner.useDelimiter("\\Z").next();
            } catch (FileNotFoundException e2) {
                e2.printStackTrace();
            }
                try{
                    String desKey = "0123456789abcdef";   
                    byte[] keyBytes = DatatypeConverter.parseHexBinary(desKey);
                    SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");
                    SecretKey key = factory.generateSecret(new DESKeySpec(keyBytes));



                    desCipher = Cipher.getInstance("DES");



                    byte[] text = content.getBytes();
                    desCipher.init(Cipher.ENCRYPT_MODE, key);
                    byte[] textEncrypted = desCipher.doFinal(text);
                    String s = new String(textEncrypted);
                    try {
                         File statText = new File(x);
                         FileOutputStream is = new FileOutputStream(statText);
                         OutputStreamWriter osw = new OutputStreamWriter(is);    
                         Writer w = new BufferedWriter(osw);
                         w.write(s);
                         w.close();
                        } 
                 catch (IOException e3) {
                     JOptionPane.showMessageDialog(null, "something is wrong with the txt file");
                                    }


                }catch(Exception e1)
                {
                    System.out.println("relax and try again");
                }

解密代码：

 path = chooser.getSelectedFile();
             String x = path.toString();

             try {

                 Scanner scanner = new Scanner(new File(x));
                content = scanner.useDelimiter("\\Z").next();
            } catch (FileNotFoundException e2) {
                e2.printStackTrace();
            }

             try{
                 String desKey = "0123456789abcdef";   
                 byte[] keyBytes = DatatypeConverter.parseHexBinary(desKey);
                 SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");
                 SecretKey key = factory.generateSecret(new DESKeySpec(keyBytes));


                    desCipher = Cipher.getInstance("DES");


                    byte[] text = content.getBytes();




                    desCipher.init(Cipher.DECRYPT_MODE, key);               
                    byte[] textEncrypted = desCipher.doFinal(text);
                    String s = new String(textEncrypted);



                    try {
                         File statText = new File(x);
                         FileOutputStream is = new FileOutputStream(statText);
                         OutputStreamWriter osw = new OutputStreamWriter(is);    
                         Writer w = new BufferedWriter(osw);
                         w.write(s);
                         w.close();
                        } 
                 catch (IOException e3) {
                     JOptionPane.showMessageDialog(null, "something is wrong with the txt file");
                                    }

                }catch(Exception e24)
                {
                    System.out.println("relax and try again");
                }

谢谢大家。

Java：无法解密我加密的内容

2 个答案: