08-16-2017, 10:15 PM
package com.java.blowfish;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
/**
*
* @author dhanoopbhaskar
*/
public class EncryptFile {
KeyGenerator keyGenerator = null;
SecretKey secretKey = null;
Cipher cipher = null;
public EncryptFile() {
try {
/**
* Create a Blowfish key
*/
keyGenerator = KeyGenerator.getInstance("Blowfish");
secretKey = keyGenerator.generateKey();
/**
* Create an instance of cipher mentioning the name of algorithm
* - Blowfish
*/
cipher = Cipher.getInstance("Blowfish");
} catch (NoSuchPaddingException ex) {
System.out.println(ex);
} catch (NoSuchAlgorithmException ex) {
System.out.println(ex);
}
}
public static void main(String[] args) {
String fileToEncrypt = "fileToEncrypt.jpg";
String encryptedFile = "encryptedFile.jpg";
String decryptedFile = "decryptedFile.jpg";
String directoryPath = "C:/Users/dhanoopbhaskar/Desktop/blowfish/";
EncryptFile encryptFile = new EncryptFile();
System.out.println("Starting Encryption..");
encryptFile.encrypt(directoryPath + fileToEncrypt,
directoryPath + encryptedFile);
System.out.println("Encryption completed..");
System.out.println("Starting Decryption..");
encryptFile.decrypt(directoryPath + encryptedFile,
directoryPath + decryptedFile);
System.out.println("Decryption completed..");
}
/**
*
* @param srcPath
* @param destPath
*
* Encrypts the file in srcPath and creates a file in destPath
*/
private void encrypt(String srcPath, String destPath) {
File rawFile = new File(srcPath);
File encryptedFile = new File(destPath);
InputStream inStream = null;
OutputStream outStream = null;
try {
/**
* Initialize the cipher for encryption
*/
cipher.init(Cipher.ENCRYPT_MODE, secretKey);
/**
* Initialize input and output streams
*/
inStream = new FileInputStream(rawFile);
outStream = new FileOutputStream(encryptedFile);
byte[] buffer = new byte[1024];
int len;
while ((len = inStream.read(buffer)) > 0) {
outStream.write(cipher.update(buffer, 0, len));
outStream.flush();
}
outStream.write(cipher.doFinal());
inStream.close();
outStream.close();
} catch (IllegalBlockSizeException ex) {
System.out.println(ex);
} catch (BadPaddingException ex) {
System.out.println(ex);
} catch (InvalidKeyException ex) {
System.out.println(ex);
} catch (FileNotFoundException ex) {
System.out.println(ex);
} catch (IOException ex) {
System.out.println(ex);
}
}
/**
*
* @param srcPath
* @param destPath
*
* Decrypts the file in srcPath and creates a file in destPath
*/
private void decrypt(String srcPath, String destPath) {
File encryptedFile = new File(srcPath);
File decryptedFile = new File(destPath);
InputStream inStream = null;
OutputStream outStream = null;
try {
/**
* Initialize the cipher for decryption
*/
cipher.init(Cipher.DECRYPT_MODE, secretKey);
/**
* Initialize input and output streams
*/
inStream = new FileInputStream(encryptedFile);
outStream = new FileOutputStream(decryptedFile);
byte[] buffer = new byte[1024];
int len;
while ((len = inStream.read(buffer)) > 0) {
outStream.write(cipher.update(buffer, 0, len));
outStream.flush();
}
outStream.write(cipher.doFinal());
inStream.close();
outStream.close();
} catch (IllegalBlockSizeException ex) {
System.out.println(ex);
} catch (BadPaddingException ex) {
System.out.println(ex);
} catch (InvalidKeyException ex) {
System.out.println(ex);
} catch (FileNotFoundException ex) {
System.out.println(ex);
} catch (IOException ex) {
System.out.println(ex);
}
}
}
