LedgerSubscriber.java

package com.ripple.client.subscriptions.ledger;

import com.ripple.client.Client;
import com.ripple.client.subscriptions.ServerInfo;
import com.ripple.client.subscriptions.SubscriptionManager;
import com.ripple.client.subscriptions.TransactionSubscriptionManager;
import com.ripple.core.types.known.tx.result.TransactionResult;

import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Takes care of dropouts when subscribing to a ledger.
 */
public class LedgerSubscriber implements TransactionSubscriptionManager {
    public static final Logger logger = Logger.getLogger(LedgerSubscriber.class.getName());
    public static void log(String fmt, Object... args) {
        logger.log(Level.FINE, fmt, args);
    }

    Client client;
    PendingLedgers ledgers;

    public void notifyTransactionResult(TransactionResult tr) {
        ledgers.notifyTransactionResult(tr);
    }

    public LedgerSubscriber(final Client client) {
        this.client = client;
        ledgers = new PendingLedgers(client);
        subscribeToTransactions();
        bindLedgerCloseHandler();
    }

    private void subscribeToTransactions() {
        client.subscriptions.addStream(SubscriptionManager.Stream.transactions);
    }

    private void bindLedgerCloseHandler() {
        client.on(Client.OnLedgerClosed.class, new Client.OnLedgerClosed() {
            @Override
            public void called(final ServerInfo serverInfo) {
                final long ledger_index = serverInfo.ledger_index;

                ledgers.trackMissingLedgersInClearedLedgerHistory();
                ledgers.logPendingLedgers();

                // We can see how many transactions are pending
                PendingLedger ledger = ledgers.getOrAddLedger(ledger_index);
                ledger.expectedTxns = serverInfo.txn_count;

                // We may already be tracking the ledger from below block
                if (ledger.status == PendingLedger.Status.pending) {
                    ledgers.checkHeader(ledger);
                }

                for (Long stalledOrGapLedger : ledgers.pendingLedgerIndexes()) {
                    PendingLedger stalled = ledgers.getOrAddLedger(stalledOrGapLedger);
                    if (stalled.status == PendingLedger.Status.pending) {
                        ledgers.checkHeader(stalled);
                        break;
                    }
                }
            }
        });
    }
}