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Encrypt and decrypt using the DES algorithm
import java.security.*;
import javax.crypto.*;
//
// encrypt and decrypt using the DES private key algorithm
public class PrivateExample {
public static void main(String[] args) throws Exception {
//
// check args and get plaintext
if (args.length != 1) {
System.err.println("Usage: java PrivateExample text");
System.exit(1);
}
// byte[] plainText = args[0].getBytes("UTF8");
String ss = "Hello world, haris is here!";
byte[] plainText = ss.getBytes();
//
// get a DES private key
System.out.println("\nStart generating DES key");
KeyGenerator keyGen = KeyGenerator.getInstance("DES");
keyGen.init(56);
Key key = keyGen.generateKey();
System.out.println("Finish generating DES key");
//
// get a DES cipher object and print the provider
Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
System.out.println("\n" + cipher.getProvider().getInfo());
//
// encrypt using the key and the plaintext
System.out.println("\nStart encryption");
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] cipherText = cipher.doFinal(plainText);
System.out.println("Finish encryption: ");
System.out.println(new String(cipherText, "UTF8"));
//
// decrypt the ciphertext using the same key
System.out.println("\nStart decryption");
cipher.init(Cipher.DECRYPT_MODE, key);
byte[] newPlainText = cipher.doFinal(cipherText);
System.out.println("Finish decryption: ");
System.out.println(new String(newPlainText, "UTF8"));
}
}
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