我正在尝试将编码后的文本导出为txt文件。但在出口和进口的某个地方出了问题。在同一个应用程序中，我可以导出和导入就好了。编码和解码。但是，当我关闭应用程序并再次运行它然后导入以前编码的文本时，输入会更改为它不会被解密的内容。
我认为它可能与每次运行应用程序时随机生成的密码有关。但我不知道如何解决它。
警告。这个应用程序变化很大。对不起，我很抱歉。
package crypt;
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Scanner;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
/**
* This program imports exports encrypts and decrypts any text file.
* The known bugs are that you can't reuse exported and imported files
* outside of the current application session.
* This may be cause by the cipher having different random values in place
* when it restarts the program. 2 ciphers are never the same.
* This encryption application is nearly impossible to decrypt.
* Yet do to the lack of being able to reuse the same cipher over 2 applications
* the program is all but useless.
* @author qward
*
*/
@SuppressWarnings("serial")
public class Crypt extends JFrame {
final private Cipher cipher = Cipher.getInstance("AES");
/**
* @throws NoSuchAlgorithmException
* @throws NoSuchPaddingException
*/
public Crypt() throws NoSuchAlgorithmException, NoSuchPaddingException {
super("Cypt");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(600, 600);
setLocationRelativeTo(null);
setResizable(false);
// sets one cipher for encode and decode
// Initiating Components
JFileChooser fileChooser = new JFileChooser();
fileChooser.setCurrentDirectory(new File(System
.getProperty("user.home")));
JPanel left = new JPanel();
JPanel right = new JPanel();
JPanel bottom = new JPanel();
JPanel top = new JPanel();
left.setLayout(new BorderLayout());
right.setLayout(new BorderLayout());
bottom.setLayout(new FlowLayout());
top.setLayout(new FlowLayout());
JLabel inputLabel = new JLabel("Input");
JLabel outputLabel = new JLabel("Output");
JButton generateKey = new JButton("Generate Key");
final JTextArea input = new JTextArea(20, 25);
final JTextArea output = new JTextArea(20, 25);
JScrollPane inputScroll = new JScrollPane(input);
JScrollPane outputScroll = new JScrollPane(output);
final JTextField key = new JTextField(20);
JButton encode = new JButton("encode");
JButton decode = new JButton("decode");
JButton swap = new JButton("Swap");
JMenuBar bar = new JMenuBar();
JMenu file = new JMenu("File");
JMenuItem export = export(fileChooser, output);
JMenuItem imports = imports(fileChooser, input);
file.add(imports);
file.add(export);
bar.add(file);
// Position Components
bottom.add(generateKey);
bottom.add(key);
bottom.add(encode);
bottom.add(decode);
top.add(swap);
left.add(inputScroll, BorderLayout.CENTER);
left.add(inputLabel, BorderLayout.NORTH);
right.add(outputScroll, BorderLayout.CENTER);
right.add(outputLabel, BorderLayout.NORTH);
add(left, BorderLayout.WEST);
add(right, BorderLayout.EAST);
add(bottom, BorderLayout.SOUTH);
add(top, BorderLayout.NORTH);
setJMenuBar(bar);
// Add events to buttons
encode.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
if (key.getText().length() == 16) {
output.setText(encrypt(input.getText(), new SecretKeySpec(
key.getText().getBytes(), "AES"), cipher));
} else {
JOptionPane.showMessageDialog(null,
"Please input a valid 16 character key");
}
}
});
generateKey.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
key.setText(generateKey());
}
});
decode.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
if (key.getText().length() == 16) {
output.setText(decrypt(input.getText(), new SecretKeySpec(
key.getText().getBytes(), "AES"), cipher));
} else {
JOptionPane.showMessageDialog(null,
"Please input a valid 16 character key");
}
}
});
swap.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
String temp = input.getText();
input.setText(output.getText());
output.setText(temp);
}
});
// begin
pack();
setVisible(true);
}
/**
* @param fileChooser
* @param output
* @return
*/
private JMenuItem export(final JFileChooser fileChooser,
final JTextArea output) {
JMenuItem export = new JMenuItem("Export");
export.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
int result = fileChooser.showOpenDialog(Crypt.this);
if (result == JFileChooser.APPROVE_OPTION) {
File selectedFile = fileChooser.getSelectedFile();
if (selectedFile.getName().toLowerCase().endsWith(".txt")) {
PrintWriter out = null;
try {
out = new PrintWriter(selectedFile
.getAbsolutePath());
out.print(new String(cipher.doFinal(output
.getText().getBytes())));
} catch (FileNotFoundException
| IllegalBlockSizeException
| BadPaddingException e) {
out.print(output.getText());
} finally {
out.close();
}
} else {
JOptionPane.showMessageDialog(null,
"Please Select a .txt File");
}
}
}
});
return export;
}
/**
* @param fileChooser
* @param input
* @return
*/
private JMenuItem imports(final JFileChooser fileChooser,
final JTextArea input) {
JMenuItem imports = new JMenuItem("Import");
imports.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
int result = fileChooser.showOpenDialog(Crypt.this);
if (result == JFileChooser.APPROVE_OPTION) {
File selectedFile = fileChooser.getSelectedFile();
if (selectedFile.getName().toLowerCase().endsWith(".txt")) {
Scanner in = null;
try {
in = new Scanner(new File(selectedFile
.getAbsolutePath()));
String str = "";
while (in.hasNextLine()) {
str += in.nextLine() + "\n";
}
byte[] encrypted = cipher.doFinal(input.getText()
.getBytes());
input.setText(new String(encrypted, "ISO-8859-1"));
} catch (Exception e) {
try {
in = new Scanner(new File(selectedFile
.getAbsolutePath()));
String str = "";
while (in.hasNextLine()) {
str += in.nextLine() + "\n";
}
input.setText(new String(str));
} catch (FileNotFoundException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
} finally {
in.close();
}
} else {
JOptionPane.showMessageDialog(null,
"Please Select a .txt File");
}
}
}
});
return imports;
}
/**
* @return
*/
private String generateKey() {
try {
SecureRandom random = new SecureRandom();
return new String(random.generateSeed(16), "ISO-8859-1");
} catch (UnsupportedEncodingException u) {
}
return "";
}
/**
* @param input
* @param key
* @param cipher
* @return
*/
private String encrypt(String input, Key key, Cipher cipher) {
try {
// encrypt the text
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] encrypted = cipher.doFinal(input.getBytes());
return new String(encrypted, "ISO-8859-1");
} catch (Exception e) {
e.printStackTrace();
}
return "";
}
/**
* @param input
* @param key
* @param cipher
* @return
*/
private String decrypt(String input, Key key, Cipher cipher) {
try {
// decrypt the text
cipher.init(Cipher.DECRYPT_MODE, key);
String decrypted = new String(cipher.doFinal(input
.getBytes("ISO-8859-1")));
return decrypted;
} catch (Exception e) {
e.printStackTrace();
}
return "";
}
/**
* @param args
* @throws NoSuchAlgorithmException
* @throws NoSuchPaddingException
* @throws InvalidKeyException
*/
public static void main(String[] args) throws NoSuchAlgorithmException,
NoSuchPaddingException, InvalidKeyException {
new Crypt();
}
}
答案 0 :(得分：1)
这是你随机性的来源。你可能想要保存 无论此方法返回什么，然后在下一次运行应用程序时使用它。
/**
* @return
*/
private String generateKey() {
try {
SecureRandom random = new SecureRandom();
return new String(random.generateSeed(16), "ISO-8859-1");
} catch (UnsupportedEncodingException u) {
}
return "";
}
如果您希望自己的应用行为正常，请考虑如何重做这一点 从一次跑到另一次。此外，不要使用空的catch块。