How to encrypt or decrypt a file in java

EncryDecry.java:

/*

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package com.techzoop.games;

/**

 *

 * @author Arpan

 */

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import javax.crypto.Cipher;

import javax.crypto.CipherInputStream;

import javax.crypto.CipherOutputStream;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

public class EncryDecry {

public static void main(String[] ar) {

try {

String key_txt = "techzoop"; // needs to be at least 8 characters for DES

FileInputStream fis = new FileInputStream("C:\\Users\\USER\\Desktop\\export\\1.jpg");

FileOutputStream fos = new FileOutputStream("C:\\Users\\USER\\Desktop\\export\\encrypted_file.jpg");

func_encrypt(key_txt, fis, fos);

FileInputStream fis2 = new FileInputStream("C:\\Users\\USER\\Desktop\\export\\encrypted_file.jpg");

FileOutputStream fos2 = new FileOutputStream("C:\\Users\\USER\\Desktop\\export\\decrypted_file.jpg");

func_decrypt(key_txt, fis2, fos2);

} catch (Throwable e) {

e.printStackTrace();

}

}

public static void func_encrypt(String key_txt, InputStream is, OutputStream os) throws Throwable {

encrypt_Decrypt(key_txt, Cipher.ENCRYPT_MODE, is, os);

}

public static void func_decrypt(String key_txt, InputStream is, OutputStream os) throws Throwable {

encrypt_Decrypt(key_txt, Cipher.DECRYPT_MODE, is, os);

}

public static void encrypt_Decrypt(String key_txt, int mode, InputStream is, OutputStream os) throws Throwable {

DESKeySpec dks = new DESKeySpec(key_txt.getBytes());

SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");

SecretKey desKey = skf.generateSecret(dks);

Cipher cipher = Cipher.getInstance("DES"); // DES/ECB/PKCS5Padding for SunJCE

if (mode == Cipher.ENCRYPT_MODE) {

cipher.init(Cipher.ENCRYPT_MODE, desKey);

CipherInputStream cis = new CipherInputStream(is, cipher);

doCopy(cis, os);

} else if (mode == Cipher.DECRYPT_MODE) {

cipher.init(Cipher.DECRYPT_MODE, desKey);

CipherOutputStream cos = new CipherOutputStream(os, cipher);

doCopy(is, cos);

}

}

public static void doCopy(InputStream is, OutputStream os) throws IOException {

byte[] bytes = new byte[64];

int numBytes;

while ((numBytes = is.read(bytes)) != -1) {

os.write(bytes, 0, numBytes);

}

os.flush();

os.close();

is.close();

}

}

***If you are facing any issues, then feel free to ask us.

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