TransfersService transfersService = IntxServiceFactory.createTransfersService(client);
WithdrawToCounterpartyIdRequest request = new WithdrawToCounterpartyIdRequest.Builder()
    .portfolio("portfolio_id")
    .counterpartyId("counterparty_id")
    .asset("BTC")
    .amount("1")
    .build();
WithdrawToCounterpartyIdResponse response = transfersService.withdrawToCounterpartyId(request);

For more information, please visit the INTX Java SDK.