code: package org.omnetpp.scave.writers;
  
  /**
   * Simulation time provider interface, for use with IOutputVectorManager.
   * A simulation time provider should be implemented by the
   * simulation package, and passed to instances of IOutputVectorManager.
   * The <code>getSimulationTime()</code> method will be used to generate a
   * timestamp for values recorded via the <code>record(double value)</code>
   * method of IOutputVector.
   *
   * @author Andras
   */
  public interface ISimulationTimeProvider {
      /**
       * Returns the current simulation time.
       */
      Number getSimulationTime();
  
      /**
       * Returns the current event number. If the simulator does
       * not keep track of event numbers, it should return -1.
       * This method is currently unused.
       */
      long getEventNumber();
  }
  