Transaction

Represents a transaction in the Stellar network.

A transaction is a grouping of operations that are executed together atomically. All operations must succeed for the transaction to succeed. If any operation fails, all effects are rolled back.

Transaction Structure

A transaction consists of:

• Source Account: The account that originates the transaction and pays the fee

• Fee: Total fee in stroops (baseFee * operations.size)

• Sequence Number: Must be exactly sourceAccount.sequence + 1

• Operations: List of 1-100 operations to execute

• Memo: Optional memo (up to 28 bytes for text memos)

• Preconditions: Optional time bounds, ledger bounds, etc.

• Signatures: List of signatures authorizing the transaction

Building Transactions

Use TransactionBuilder to construct transactions:

val sourceAccount = Account("GABC...", 1234567890)
val transaction = TransactionBuilder(sourceAccount, Network.TESTNET)
    .addOperation(
        PaymentOperation(
            destination = "GDEF...",
            asset = AssetTypeNative,
            amount = "10.0"
        )
    )
    .addMemo(MemoText("Payment for services"))
    .setTimeout(300) // 5 minutes
    .setBaseFee(100)
    .build()

// Sign with source account keypair
transaction.sign(sourceKeypair)

// Submit to Horizon
val response = horizonServer.submitTransaction(transaction)

Fee Calculation

The transaction fee is calculated as: baseFee * operations.size

The minimum base fee is 100 stroops (0.00001 XLM), so:

• 1 operation: 100 stroops = 0.00001 XLM

• 10 operations: 1,000 stroops = 0.0001 XLM

• 100 operations: 10,000 stroops = 0.001 XLM

Sequence Numbers

Each account has a sequence number that must be incremented with each transaction. The transaction's sequence number must be exactly sourceAccount.sequence + 1. After successful execution, the account's sequence number becomes the transaction's sequence number.

See also