code: public void initialize() {
          Coin balance = Main.bitcoin.wallet().getBalance();
          checkState(!balance.isZero());
          new BitcoinAddressValidator(Main.params, address, sendBtn);
          new TextFieldValidator(amountEdit, text ->
                  !WTUtils.didThrow(() -> checkState(Coin.parseCoin(text).compareTo(balance) <= 0)));
          amountEdit.setText(balance.toPlainString());
          address.setPromptText(Address.fromKey(Main.params, new ECKey(), Main.PREFERRED_OUTPUT_SCRIPT_TYPE).toString());
      }
docs: Called by FXMLLoader