Get the input data of a transaction with web3j

Question

How can I retrieve transaction details (including the input data) from a txHash using Web3j?

I tried the following method:

public void buscarHhash(Web3j web3, String txHash) throws IOException {
    String inputdata;

    EthSendTransaction ethSendTransaction = null;
    Request<?, EthTransaction> transactionReceipt = web3.ethGetTransactionByHash(txHash);
    transactionReceipt.send().getTransaction()
            .ifPresent(tx -> {
                inputdata = tx.getInput();
            });
}

This method does not seem to work, and I don't know if I'm doing it right.

Does anyone know how to do it? Not necessarily with the method that I used.

Answer 1

The error you're having appears to be from your handling of the optional value through a lambda function. You could perhaps try it the following way (without the use of a lambda function):

String inputdata;

Optional<Transaction> tx = web3.ethGetTransactionByHash(txHash).send().getTransaction();

if (tx.isPresent()) {
    inputdata = tx.get().getInput();
}