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我有一个Java程序。这是一个AES加密 - 解密程序。该程序有一个图形用户界面,可以输入字符串并显示AES加密字符串。该程序还使用代码中写入的解密函数显示原始字符串。界面是这样的,当输入字符串并且点击转换按钮时,加密和解密结果显示在面板中。这是程序。AES加密 - 如何以后解密加密的字符串?
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.io.*;
public class AESGUI extends JPanel {
public static void main(String[] args) {
JFrame frame = new JFrame("AES Encryption");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(600,300));
frame.setLocationRelativeTo(null);
frame.setResizable(false);
AESGUI p = new AESGUI();
frame.getContentPane().add(p);
frame.pack();
frame.setVisible(true);
}
private JTextField in;
private JTextArea out;
public AESGUI() {
JLabel info = new JLabel("Type any String");
in = new JTextField(20);
JButton encrypt = new JButton("Encrypt");
out = new JTextArea(10,40);
out.setEditable(false);
encrypt.addActionListener(new encryptListener());
in.addActionListener(new encryptListener());
add(info);
add(in);
add(encrypt);
add(out);
add(new JScrollPane(out));
}
private class encryptListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
String data = in.getText();
if (data.length() == 0) { }
else
try {
String en = encrypt(data);
out.append("Encrypted string: " + en + "\n");
out.append("Original String: " + decrypt(en) + "\n\n");
} catch(Exception ex) { }
}
}
public String asHex(byte[] buf) {
StringBuffer strbuf = new StringBuffer(buf.length * 2);
int i;
for (i = 0; i < buf.length; i++) {
if (((int) buf[i] & 0xff) < 0x10)
strbuf.append("0");
strbuf.append(Long.toString((int) buf[i] & 0xff, 16));
}
return strbuf.toString();
}
private SecretKeySpec skeySpec;
private Cipher cipher;
private byte[] encrypted;
public String encrypt(String str) throws Exception {
// Get the KeyGenerator
KeyGenerator kgen = KeyGenerator.getInstance("AES");
kgen.init(128); // 192 and 256 bits may not be available
// Generate the secret key specs.
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
skeySpec = new SecretKeySpec(raw, "AES");
// Instantiate the cipher
cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
encrypted = cipher.doFinal(str.getBytes());
return asHex(encrypted);
}
public String decrypt(String str) throws Exception {
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] original = cipher.doFinal(encrypted);
String originalString = new String(original);
return originalString;
}
}
该程序不告诉用户哪个密钥用于加密字符串。因为它没有告诉用户密钥,用户以后不能解密加密的字符串。该程序以十六进制编码显示加密的字符串。为了稍后对字符串进行解密,最好是更改程序以便程序根据密码创建一个密钥或者更好地将程序改变为向用户显示随机生成的密钥后来解密字符串?
程序的目的是什么?你想达到什么目的? – ewernli 2009-12-16 09:00:32