import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
class DesEncrypter {
Cipher ecipher;
Cipher dcipher;
DesEncrypter(SecretKey key) throws Exception {
ecipher = Cipher.getInstance("DES");
dcipher = Cipher.getInstance("DES");
ecipher.init(Cipher.ENCRYPT_MODE, key);
dcipher.init(Cipher.DECRYPT_MODE, key);
}
public String encrypt(String str) throws Exception {
// Encode the string into bytes using utf-8
byte[] utf8 = str.getBytes("UTF8");
// Encrypt
byte[] enc = ecipher.doFinal(utf8);
// Encode bytes to base64 to get a string
return new sun.misc.BASE64Encoder().encode(enc);
}
public String decrypt(String str) throws Exception {
// Decode base64 to get bytes
byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str);
byte[] utf8 = dcipher.doFinal(dec);
// Decode using utf-8
return new String(utf8, "UTF8");
}
}
public class Main {
public static void main(String[] argv) throws Exception {
SecretKey key = KeyGenerator.getInstance("DES").generateKey();
DesEncrypter encrypter = new DesEncrypter(key);
String encrypted = encrypter.encrypt("Don't tell anybody!");
String decrypted = encrypter.decrypt(encrypted);
}
}
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