Randomaccessfile class for file encryption

file Encryption / decryption example.

Package io;

Import java.io.*;

public class Encrypt {

private file file; storing file object information

Byte[] BUF; buffer that stores all data in the file randomaccessfile fp;

Constructs a filed object store with the file specified by the parameter filename

Allocating storage space equal to the length of the file for the buffer buf

Public Encrypt (String filename) {

File=new File (filename);

Buf=new byte[(int) file.length ()];

}

Public Encrypt (File destfile) {

File = DestFile;

BUF = new byte[(int) file.length ()];

}

open files in read-write mode

public void OpenFile () throws filenotfoundexception{

Fp=new randomaccessfile (file, "RW");

}

Close File

public void CloseFile () throws ioexception{

Fp.close ();

}

encrypting / decrypting a file

public void Coding () throws ioexception{

reads the contents of the file into the buffer fp.read (BUF);

to reverse the contents of a buffer

for (int i=0;i<buf.length;i++)

Buf[i]= (Byte) (~buf[i]);

position the file pointer to the file header

Fp.seek (0);

writes the contents of the buffer to a file fp.write (BUF);

}

public static void Main (string[] args) {

Encrypt OA;

if (args.length<1) {

System.out.println (" you need to specify the name of the encrypted file!") ");

Return

}

try {

OA = new Encrypt (args[0]);

Oa.openfile ();

Oa.coding ();

Oa.closefile ();

System.out.println (" file encryption succeeded!") ");

} catch (FileNotFoundException e) {

System.out.println (" File not found:" +args[0]);

}catch (IOException e) {

System.out.println (" file read/write error :" +args[0]);

}

}

}

Randomaccessfile class for file encryption