Can I get help for this please. Write a program called \"RSA.java\" to implement

Question

Can I get help for this please. Write a program called "RSA.java" to implement RSA encryption/decryption.

Specifically, your program should read several parameters, plaintext and ciphertext from a file named “input.txt” (in the same directory). Then your program should create a file named “output.txt” (in the same directory) and prints the private key information, encryption, and decryption results to “output.txt”. (Please check the attached sample files “input.txt” and “output.txt”.)
For “input.txt” file:
The first line is a prime number p (Hint: You may need use BigInteger datatype)

The second line is another prime number q

The third line is a randomly selected integer e, satisfying gcd(e, (n)) = 1, where (n) = ( p-1 ) * ( q-1 )

The fourth line is the plaintext M

The fifth line is the ciphertext C

For “output.txt” file:
The first line is d satisfying ed mod (n) = 1

The second line is the ciphertext of the plaintext M in input.txt

The third line is the plaintext of the ciphertext C in input.txt

Here is my inputt.xt:

Here is my output.txt:

Explanation / Answer

import java.io.DataInputStream;

import java.io.IoException;

import java.math.BigInteger;

import java.util.Random

public class RSA

{

private BigInteger p;

private BigInteger q;

private BigInteger n;

private BigInteger phi;

private BigInteger e;

private BigInteger d;

private int bitlength =1024;

private Random r;

public RSA()

{

r=new Random();

p=BigInteger.probableprime(bitlength, r);

q=BigInteger.probableprime(bitlength, r);

n=p.multiply(q);

phi=p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE));

e=BigInteger.probableprime(bitlength/2, r);

while (phi.gcd(e).compareTo(BIgInteger.ONE)> 0 && e.cmpareTo(phi)<0)

{

e.add(BigInteger.ONE);

}

d=e.modInverse(phi);

}

public RSA (BigInteger e, BigInteger d,BigInteger n)

{

this.e=e;

this.d=d;

this.n=n;

}

public static void main(string[] args)throws IoException

{

RSA rsa =new RSA();

DataInputStream in=new DataInputStream(System.in);

string teststring;

system.out.println("enter the plain text");

teststring=in.readline();

system.out.println("encrypted string:"+ teststring);

system.out.println("string in bytes"+bytesTostring(teststring.getbytes());

byte[] encrypted=rsa.encrypt(teststring.getbytes());

byte[] decrypted=rsa decrypt(encrypted);

system.out.println("decrypting bytes"+bytesTostring(decrypted));

system.out.println("decrypted string"+new string(decrypted));

}

private static string bytesTostriing (byte[] encrypted)

{

string test=" ";

for(byte b: encrypted)

{

test+=byte.tostring(b);

}

return test;

}

public byte [] encrypt (byte[] message)

{

return(new BigInteger(message)).modPow(e,n).tobytearray();

}

public byte [] decrypt (byte[] message)

{

return(new BigInteger(message)).modPow(d,n).tobytearray();

}

}

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