hello everyone,i need to make an encryption/decryption program
and I'm almost finished, the problem is when i tried to add some gui an error about throwing exception keeps showing..
this is the code without the gui and it works just fine because the throws Exception is in the main..
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.util.*;
public class FileEncryptor
{
private static String filename;
private static String password;
private static FileInputStream inFile;
private static FileOutputStream outFile;
public static void main(String[] args) throws Exception
{
// File to encrypt. It does not have to be a text file!
filename = "myFile.txt";
// Password must be at least 8 characters (bytes) long
String password = "super_secret";
inFile = new FileInputStream(filename);
outFile = new FileOutputStream(filename + ".des");
// Use PBEKeySpec to create a key based on a password.
// The password is passed as a character array
PBEKeySpec keySpec = new PBEKeySpec(password.toCharArray());
SecretKeyFactory keyFactory =
SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey passwordKey = keyFactory.generateSecret(keySpec);
// PBE = hashing + symmetric encryption. A 64 bit random
// number (the salt) is added to the password and hashed
// using a Message Digest Algorithm (MD5 in this example.).
// The number of times the password is hashed is determined
// by the interation count. Adding a random number and
// hashing multiple times enlarges the key space.
byte[] salt = new byte[8];
Random rnd = new Random();
rnd.nextBytes(salt);
int iterations = 100;
//Create the parameter spec for this salt and interation count
PBEParameterSpec parameterSpec = new PBEParameterSpec(salt, iterations);
// Create the cipher and initialize it for encryption.
Cipher cipher = Cipher.getInstance("PBEWithMD5AndDES");
cipher.init(Cipher.ENCRYPT_MODE, passwordKey, parameterSpec);
// Need to write the salt to the (encrypted) file. The
// salt is needed when reconstructing the key for decryption.
outFile.write(salt);
// Read the file and encrypt its bytes.
byte[] input = new byte[64];
int bytesRead;
while ((bytesRead = inFile.read(input)) != -1)
{
byte[] output = cipher.update(input, 0, bytesRead);
if (output != null) outFile.write(output);
}
byte[] output = cipher.doFinal();
if (output != null) outFile.write(output);
inFile.close();
outFile.flush();
outFile.close();
}
}and this is my version with the added gui...
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.Toolkit;
import java.io.*;
import java.io.FileWriter;
import java.io.IOException;
//import javax.swing.JFileChooser;
import javax.swing.filechooser.FileFilter;
import javax.swing.filechooser.FileNameExtensionFilter;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.util.*;
public class Encrypt extends JPanel {
private Button btn_load;
private Button btn_save;
private TextField txt_name;
private Label lbl_name;
private TextField txt_pass;
private Label lbl_pass;
private Label lbl_info;
private File file;
private static String filename;
private static String password;
private static FileInputStream inFile;
private static FileOutputStream outFile;
public Encrypt(){
//construct components
btn_load = new Button ("Load File");
btn_save = new Button ("Save Encrypted File");
txt_name = new TextField (100);
lbl_name = new Label ("File Name:");
txt_pass = new TextField (100);
lbl_pass = new Label ("Pass Key:");
lbl_info = new Label ("Password must be at least 8 characters (bytes) long");
//adjust size and set layout
setPreferredSize (new Dimension (420, 126));
setLayout (null);
//add components
add (btn_load);
add (btn_save);
add (txt_name);
add (lbl_name);
add (txt_pass);
add (lbl_pass);
add (lbl_info);
//set component bounds (only needed by Absolute Positioning)
btn_load.setBounds (315, 5, 100, 25);
btn_save.setBounds (110, 95, 305, 25);
txt_name.setBounds (110, 5, 200, 25);
lbl_name.setBounds (5, 5, 100, 25);
txt_pass.setBounds (110, 35, 305, 25);
lbl_pass.setBounds (5, 35, 100, 25);
lbl_info.setBounds (110, 65, 305, 25);
//set actions
btn_load.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
JFileChooser fileopen = new JFileChooser();
FileFilter filter = new FileNameExtensionFilter("Text Documents (*.txt)", "txt");
fileopen.addChoosableFileFilter(filter);
int ret = fileopen.showDialog(null, "Open file");
switch (ret) {
case JFileChooser.APPROVE_OPTION:
file = fileopen.getSelectedFile();
txt_name.setText(file.getName());
break;
case JFileChooser.CANCEL_OPTION:
file = null;
txt_name.setText("");
break;
case JFileChooser.ERROR_OPTION:
file = null;
txt_name.setText("");
break;
}
}
});
btn_save.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae){
String saveLoc = null;
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new java.io.File("."));
chooser.setDialogTitle("choosertitle");
chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
chooser.setAcceptAllFileFilterUsed(false);
switch (chooser.showSaveDialog(null)) {
case JFileChooser.APPROVE_OPTION:
//System.out.println("getCurrentDirectory(): " + chooser.getCurrentDirectory());
//System.out.println("getSelectedFile() : " + chooser.getSelectedFile());
saveLoc = chooser.getSelectedFile().toString();
break;
case JFileChooser.CANCEL_OPTION:
//System.out.println("No Selection ");
saveLoc = null;
break;
case JFileChooser.ERROR_OPTION:
//System.out.println("No Selection ");
saveLoc = null;
break;
}
if (saveLoc != null) {
// File to encrypt. It does not have to be a text file!
//filename = file;
// Password must be at least 8 characters (bytes) long
password = txt_pass.getText();
inFile = new FileInputStream(file);
outFile = new FileOutputStream(saveLoc + "\\" + file.getName() + ".des");
// Use PBEKeySpec to create a key based on a password.
// The password is passed as a character array
PBEKeySpec keySpec = new PBEKeySpec(password.toCharArray());
SecretKeyFactory keyFactory =
SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey passwordKey = keyFactory.generateSecret(keySpec);
// PBE = hashing + symmetric encryption. A 64 bit random
// number (the salt) is added to the password and hashed
// using a Message Digest Algorithm (MD5 in this example.).
// The number of times the password is hashed is determined
// by the interation count. Adding a random number and
// hashing multiple times enlarges the key space.
byte[] salt = new byte[8];
Random rnd = new Random();
rnd.nextBytes(salt);
int iterations = 100;
//Create the parameter spec for this salt and interation count
PBEParameterSpec parameterSpec = new PBEParameterSpec(salt, iterations);
// Create the cipher and initialize it for encryption.
Cipher cipher = Cipher.getInstance("PBEWithMD5AndDES");
cipher.init(Cipher.ENCRYPT_MODE, passwordKey, parameterSpec);
// Need to write the salt to the (encrypted) file. The
// salt is needed when reconstructing the key for decryption.
outFile.write(salt);
// Read the file and encrypt its bytes.
byte[] input = new byte[64];
int bytesRead;
while ((bytesRead = inFile.read(input)) != -1)
{
byte[] output = cipher.update(input, 0, bytesRead);
if (output != null) outFile.write(output);
}
byte[] output = cipher.doFinal();
if (output != null) outFile.write(output);
inFile.close();
outFile.flush();
outFile.close();
}
}
});
}
public static void main (String[] args){
Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
int x = (dim.width-300)/2;
int y = (dim.height-280)/2;
JFrame frame = new JFrame ("Encryptor");
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add (new Encrypt());
frame.setLocation (x,y);
frame.setResizable(false);
frame.pack();
frame.setVisible (true);
}
}i dont know what to do next and where to put the throw exception to make this work..im just a new to java and i think this isn't that big of a problem to you guys..hope you can help me..thanks :icon_smile:
BTW this is the decryption for the working code..
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.util.*;
public class FileDecryptor
{
private static String filename;
private static String password;
private static FileInputStream inFile;
private static FileOutputStream outFile;
/**
* Note: All kinds of exceptions can be thrown in main.
* See the API documentation for each method used.
*/
public static void main(String[] args) throws Exception
{
// File to decrypt.
filename = "myFile.txt.des";
String password = "super_secret";
inFile = new FileInputStream(filename);
outFile = new FileOutputStream(filename + ".dcr");
PBEKeySpec keySpec = new PBEKeySpec(password.toCharArray());
SecretKeyFactory keyFactory =
SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey passwordKey = keyFactory.generateSecret(keySpec);
// Read in the previouly stored salt and set the iteration count.
byte[] salt = new byte[8];
inFile.read(salt);
int iterations = 100;
PBEParameterSpec parameterSpec = new PBEParameterSpec(salt, iterations);
// Create the cipher and initialize it for decryption.
Cipher cipher = Cipher.getInstance("PBEWithMD5AndDES");
cipher.init(Cipher.DECRYPT_MODE, passwordKey, parameterSpec);
byte[] input = new byte[64];
int bytesRead;
while ((bytesRead = inFile.read(input)) != -1)
{
byte[] output = cipher.update(input, 0, bytesRead);
if (output != null)
outFile.write(output);
}
byte[] output = cipher.doFinal();
if (output != null)
outFile.write(output);
inFile.close();
outFile.flush();
outFile.close();
}
}