MultiExecutionListener

The MultiExecutionListener is a fan-out dispatcher for execution events.
It enables multiple IOrderExecutionListener consumers to receive notifications for the same order events.

Purpose

To allow multiple subsystems (e.g., position tracking, analytics, risk) to simultaneously observe order fills and rejections.

Class Definition

class MultiExecutionListener : public IOrderExecutionListener {
public:
  void addListener(IOrderExecutionListener *listener);

  void onOrderFilled(const Order &order) override;
  void onOrderRejected(const Order &order, const std::string &reason) override;
};

Responsibilities

• Aggregates multiple execution listeners
• Broadcasts onOrderFilled and onOrderRejected events to all registered listeners
• Avoids duplicate registration

Use Cases

• Forward execution events to both:
• PositionManager (for state updates)
• ExecutionTracker (for latency tracking)
• Composite behavior in modular systems
• Strategy instrumentation for backtesting or debugging

Notes

• Listeners are stored as raw pointers (ownership not assumed)
• Safe from duplicate registration via internal check