Encrypt and Decrypt any File IN Android or Java

Encrypt and Decrypt any File IN Android or Java



package com.example.encryption;

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;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String key = "squirrel123"; // needs to be at least 8 characters for DES
try{ Log.e("started", "");
FileInputStream fis = new FileInputStream("sdcard/raj.jpg");

FileOutputStream fos = new FileOutputStream("sdcard/c.txt");
encrypt(key, fis, fos);

FileInputStream fis2 = new FileInputStream("sdcard/c.txt");
FileOutputStream fos2 = new FileOutputStream("sdcard/c.jpg");
decrypt(key, fis2, fos2);
}catch(Exception e){e.printStackTrace();} catch (Throwable e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
public static void encrypt(String key, InputStream is, OutputStream os) throws Throwable {
encryptOrDecrypt(key, Cipher.ENCRYPT_MODE, is, os);
}

public static void decrypt(String key, InputStream is, OutputStream os) throws Throwable {
encryptOrDecrypt(key, Cipher.DECRYPT_MODE, is, os);
}

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

DESKeySpec dks = new DESKeySpec(key.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();
}
}