Encryption and Decryption using Public and Private key pair

package bouncyCastle.encrypt;

import java.security.InvalidKeyException;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Security;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

public class EncryptDecryptDemo {
	public static void main(String[] args) throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
		
		Security.addProvider(new BouncyCastleProvider());
		
		KeyPairGenerator keyGen = null;
		keyGen = KeyPairGenerator.getInstance("RSA", "BC");
		SecureRandom random = SecureRandom.getInstance("SHA1PRNG", "SUN");
		keyGen.initialize(1024, random);

		KeyPair pair = keyGen.generateKeyPair();
		
		PrivateKey priv = pair.getPrivate();
		PublicKey pub = pair.getPublic();
		
		String inputString = "Hello World";
		//*****************Encryption*****************
		Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding","BC");
		cipher.init(Cipher.ENCRYPT_MODE, pub);
		
		byte[] input = inputString.getBytes();	  
		cipher.update(input);
		
		byte[] cipherText = cipher.doFinal(); //Encrypted Text
		
		System.out.println("The Encrypted Text is : "+new String(cipherText));
		
		
		//*****************Decryption*****************
		cipher.init(Cipher.DECRYPT_MODE, priv);
		byte[] decipheredText = cipher.doFinal(cipherText);
		
		System.out.println("The Decrypted text is  "+new String(decipheredText));
	
	}
}

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