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import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.ObjectInputStream;
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;
public class MainClass {
public static void main(String args[]) throws Exception {
ObjectInputStream ois = new ObjectInputStream(new FileInputStream("keyfile"));
DESKeySpec ks = new DESKeySpec((byte[]) ois.readObject());
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey key = skf.generateSecret(ks);
Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
c.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec((byte[]) ois.readObject()));
CipherInputStream cis = new CipherInputStream(new FileInputStream("ciphertext"), c);
BufferedReader br = new BufferedReader(new InputStreamReader(cis));
System.out.println(br.readLine());
}
}
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