package com.thiagoitagaki;

import sun.misc.BASE64Decoder;

import javax.crypto.Cipher;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.spec.PKCS8EncodedKeySpec;

public class Main {

    public static void main(String[] args) throws IOException, GeneralSecurityException {
        String keyString = "<PUT_YOUR_KEY_VALUE_HERE>";
        PrivateKey privateKey = KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(new BASE64Decoder().decodeBuffer(keyString)));

        String encryptedData = "<PUT_YOUR_ENCRYPTED_DATA_HERE>";
        String decryptedData = decrypt(privateKey, encryptedData);
        System.out.print("Raw data: " + decryptedData);
    }

    private static String decrypt(PrivateKey key, String data) throws GeneralSecurityException, IOException {
        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.DECRYPT_MODE, key);
        return new String(cipher.doFinal(new BASE64Decoder().decodeBuffer(data)));
    }

}