Sending Transactions
Any operation contracting with the TRON network is a transaction. A transaction can be TRX transfer, stake & unstake, Trigger Smart Contract, Etc.
Only resource consumption transactions are available to acquire on the chain.
The Routine for Sending
A normal routine for sending a transaction is:
Create -> Sign -> Broadcast -> (wait) -> Lookup and get receipt
Create a Transaction
Each non-inquiry function creates an unsigned transaction, for example:
public TransactionExtention transfer(String fromAddress, String toAddress, long amount) throws IllegalException {
ByteString rawFrom = parseAddress(fromAddress);
ByteString rawTo = parseAddress(toAddress);
TransferContract req = TransferContract.newBuilder()
.setOwnerAddress(rawFrom)
.setToAddress(rawTo)
.setAmount(amount)
.build();
TransactionExtention txnExt = blockingStub.createTransaction2(req);
if(SUCCESS != txnExt.getResult().getCode()){
throw new IllegalException(txnExt.getResult().getMessage().toStringUtf8());
}
return txnExt;
}
Add Extra Parameters
core.TransactionBuilder
allows you to add or modify parameters before signing, for example:
TransactionBuilder builder = new TransactionBuilder(transaction);
builder.setFeeLimit(100000000L);
builder.setMemo("memo");
//call TransactionBuilder.build() to get a new transaction
builder.build();
Note that only smart contract transactions require a fee limit.
Signing
There are two ways to sign a transaction:
Sign with the binding private key
Every ApiWrapper
instance is initiated with a private key(or a hexadecimal string of 64 characters in length). Simply sign a transaction like this:
Transction signedTransaction = wrapper.signTransaction(transaction);
Sign with a specific private key
Regardless of the binding private key, you can use any private key to sign the transaction, like below:
Transaction signedTransaction = wrapper.signTransaction(transaction, SECP256K1.KeyPair);
Refer to org.tron.trident.crypto.SECP256K1
for construct an SECP256K1.KeyPair
.
Broadcast
Transaction hash may change due to any modification to the original transaction (except the signature).
Transaction hash is re-calculated inside the function of ApiWrapper.broadcastTransaction(Transaction txn)
before transaction is broadcasted.
wrapper.broadcastTransaction(signedTransaction);
//return transaction hash if successfully broadcasted, otherwise the error code
Updated over 3 years ago