CODE EXAMPLE FOR JAVA

encryption

package com.javacodegeeks.snippets.core;
 
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.Security;
import java.security.spec.AlgorithmParameterSpec;
 
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
 
public class Main {
 
    static Cipher ce;
    static Cipher cd;
 
    public static void main(String args[]) throws Exception {
 
  Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
 
  SecretKey skey = KeyGenerator.getInstance("DES").generateKey();
 
  byte[] initializationVector = new byte[]{0x10, 0x10, 0x01, 0x04, 0x01, 0x01, 0x01, 0x02};
 
  AlgorithmParameterSpec algParameters = new IvParameterSpec(initializationVector);
 
  ce = Cipher.getInstance("DES/CBC/PKCS5Padding");
 
  cd = Cipher.getInstance("DES/CBC/PKCS5Padding");
 
  ce.init(Cipher.ENCRYPT_MODE, skey, algParameters);
 
  cd.init(Cipher.DECRYPT_MODE, skey, algParameters);
 
  FileInputStream is = new FileInputStream("C:/Users/nikos7/Desktop/output.txt");
 
  FileOutputStream os = new FileOutputStream("C:/Users/nikos7/Desktop/output2.txt");
 
  int dataSize = is.available();
 
  byte[] inbytes = new byte[dataSize];
 
  is.read(inbytes);
 
  String str2 = new String(inbytes);
 
  System.out.println("Input file contentn" + str2 + "n");
 
  write_encode(inbytes, os);
 
  os.flush();
 
  is.close();
 
  os.close();
 
  System.out.println("Ecrypted Content to output2.txtn");
 
  is = new FileInputStream("C:/Users/nikos7/Desktop/output2.txt");
 
  byte[] decBytes = new byte[dataSize];
 
  read_decode(decBytes, is);
 
  is.close();
 
  String str = new String(decBytes);
 
  System.out.println("Decrypted file contents:n" + str);
 
    }
 
    public static void write_encode(byte[] bytes, OutputStream output) throws Exception {
 
  CipherOutputStream cOutputStream = new CipherOutputStream(output, ce);
 
  cOutputStream.write(bytes, 0, bytes.length);
 
  cOutputStream.close();
    }
 
    public static void read_decode(byte[] bytes, InputStream input) throws Exception {
 
  CipherInputStream cInputStream = new CipherInputStream(input, cd);
 
  int position = 0, i;
 
  while ((i = cInputStream.read()) != -1) {
 
bytes[position] = (byte) i;
 
position++;
 
  }
    }
}