ServerDecrypt.java

public class ServerDecrypt {

  static String privateKey = "<your_private_key_here>";
  static String encryptedTextString = "<your_received_encrypted_text_here>";
  static String encryptedSecretKeyString = "<your_received_encrypted_secret_key_here>";

  public static void main(String args[]) {

    try {

      // 1. Get private key
      PKCS8EncodedKeySpec privateSpec = new PKCS8EncodedKeySpec(Base64.decode(privateKey, Base64.DEFAULT));
      KeyFactory keyFactory = KeyFactory.getInstance("RSA");
      PrivateKey privateKey = keyFactory.generatePrivate(privateSpec);

      // 2. Decrypt encrypted secret key using private key
      Cipher cipher1 = Cipher.getInstance("RSA/ECB/OAEPWithSHA1AndMGF1Padding");   
      cipher1.init(Cipher.DECRYPT_MODE, privateKey);  
      byte[] secretKeyBytes = cipher1.doFinal(Base64.decode(encryptedSecretKeyString, Base64.DEFAULT));
      SecretKey secretKey = new SecretKeySpec(secretKeyBytes, 0, secretKeyBytes.length, "AES");

      // 3. Decrypt encrypted text using secret key
      byte[] raw = secretKey.getEncoded();
      SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
      Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
      cipher.init(Cipher.DECRYPT_MODE, skeySpec, new IvParameterSpec(new byte[16]));
      byte[] original = cipher.doFinal(Base64.decode(encryptedTextString, Base64.DEFAULT));
      String text = new String(original, Charset.forName("UTF-8"));

      // 4. Print the original text sent by client
      System.out.println("text\n" + text + "\n\n");

    } catch (NoSuchAlgorithmException | InvalidKeySpecException | InvalidKeyException | NoSuchPaddingException | IllegalBlockSizeException | BadPaddingException | InvalidAlgorithmParameterException e) {
      e.printStackTrace();
    }
  }
}