presto-main/src/main/java/io/prestosql/operator/JoinBridgeManager.java/JoinBridgeManager/initializeIfNecessary
class JoinBridgeManager:    private void initializeIfNecessary()
    {
        if (!initialized.get()) {
            synchronized (this) {
                if (initialized.get()) {
                    return;
                }
                int finalProbeFactoryCount = probeFactoryCount.get();
                internalJoinBridgeDataManager = internalJoinBridgeDataManager(probeExecutionStrategy, buildExecutionStrategy, joinBridgeProvider, finalProbeFactoryCount, buildOuter ? 1 : 0);
                initialized.set(true);
            }
        }
    }