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Creates a 1024 bit RSA key pair and stores it to the filesystem as two files

import java.io.ByteArrayOutputStream; import java.io.FileOutputStream; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.SecureRandom; import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.PBEKeySpec; import javax.crypto.spec.PBEParameterSpec; public class MainClass {   public static void main(String[] args) throws Exception {     String password = "password";     KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");     keyPairGenerator.initialize(1024);     KeyPair keyPair = keyPairGenerator.genKeyPair();     String publicKeyFilename = "public";     byte[] publicKeyBytes = keyPair.getPublic().getEncoded();     FileOutputStream fos = new FileOutputStream(publicKeyFilename);     fos.write(publicKeyBytes);     fos.close();     String privateKeyFilename = "privateKeyFilename";     byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();     byte[] encryptedPrivateKeyBytes = passwordEncrypt(password.toCharArray(), privateKeyBytes);     fos = new FileOutputStream(privateKeyFilename);     fos.write(encryptedPrivateKeyBytes);     fos.close();   }   private static byte[] passwordEncrypt(char[] password, byte[] plaintext) throws Exception {     int MD5_ITERATIONS = 1000;     byte[] salt = new byte[8];     SecureRandom random = new SecureRandom();     random.nextBytes(salt);     PBEKeySpec keySpec = new PBEKeySpec(password);     SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithSHAAndTwofish-CBC");     SecretKey key = keyFactory.generateSecret(keySpec);     PBEParameterSpec paramSpec = new PBEParameterSpec(salt, MD5_ITERATIONS);     Cipher cipher = Cipher.getInstance("PBEWithSHAAndTwofish-CBC");     cipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);     byte[] ciphertext = cipher.doFinal(plaintext);     ByteArrayOutputStream baos = new ByteArrayOutputStream();     baos.write(salt);     baos.write(ciphertext);     return baos.toByteArray();   } }