Package cs2030.simulator

Class RandomGenerator

  • public class RandomGenerator
extends java.lang.Object
    Encapsulates multiple streams of pseudo-random numbers specifically for use with the shop simulator. the RandomGenerator is initialized with a seed, the arrival rate (lambda) and the service rate (mu). There are two streams of random numbers here, one for inter arrival time, and the other for service time.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private double customerArrivalRate
      The customer arrival rate (lambda).
      private double customerServiceRate
      The customer service rate (mu).
      private java.util.Random rngArrival
      Random number stream for arrival rate.
      private java.util.Random rngCustomerType
      Random number stream for customer type.
      private java.util.Random rngRest
      Random number stream for probability of resting.
      private java.util.Random rngRestPeriod
      Random number stream for resting period.
      private java.util.Random rngService
      Random number stream for service rate.
      private java.util.Random rngTimeoutPeriod
      Random number stream for timeout period.
      private double serverRestingRate
      The server resting rate (rho).

    • Constructor Summary

      Constructors 
      Constructor Description
      RandomGenerator​(int seed, double lambda, double mu, double rho)
      Create a new RandomGenerator object.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      (package private) double genCustomerType()
      Generate a random number between 0 and 1 to determine the type of customer.
      (package private) double genInterArrivalTime()
      Generate random inter-arrival time.
      (package private) double genRandomRest()
      Generate a random number between 0 and 1 to compare to a server's probability of taking a rest.
      (package private) double genRestPeriod()
      Generate random resting period for server.
      (package private) double genServiceTime()
      Generate random service time.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • rngArrival

        private final java.util.Random rngArrival
        Random number stream for arrival rate.

      • rngService

        private final java.util.Random rngService
        Random number stream for service rate.

      • rngRest

        private final java.util.Random rngRest
        Random number stream for probability of resting.

      • rngRestPeriod

        private final java.util.Random rngRestPeriod
        Random number stream for resting period.

      • rngTimeoutPeriod

        private final java.util.Random rngTimeoutPeriod
        Random number stream for timeout period.

      • rngCustomerType

        private final java.util.Random rngCustomerType
        Random number stream for customer type.

      • customerArrivalRate

        private final double customerArrivalRate
        The customer arrival rate (lambda).

      • customerServiceRate

        private final double customerServiceRate
        The customer service rate (mu).

      • serverRestingRate

        private final double serverRestingRate
        The server resting rate (rho).

    • Constructor Detail

      • RandomGenerator

        RandomGenerator​(int seed,
                double lambda,
                double mu,
                double rho)
        Create a new RandomGenerator object.
        Parameters:
        seed - The random seed. New seeds will be derived based on this.
        lambda - The arrival rate.
        mu - The service rate.
        rho - The resting rate.

    • Method Detail

      • genInterArrivalTime

        double genInterArrivalTime()
        Generate random inter-arrival time. The inter-arrival time is modelled as an exponential random variable, characterised by a single parameter -- arrival rate.
        Returns:
        inter-arrival time for next event.

      • genServiceTime

        double genServiceTime()
        Generate random service time. The service time is modelled as an exponential random variable, characterised by a single parameter - service rate.
        Returns:
        service time for event.

      • genRandomRest

        double genRandomRest()
        Generate a random number between 0 and 1 to compare to a server's probability of taking a rest. The random number generated is used to determine whether the server takes rest after serving a customer.
        Returns:
        a random number between 0 and 1.

      • genRestPeriod

        double genRestPeriod()
        Generate random resting period for server. The resting period is modelled as an exponential random variable, characterised by a single parameter - resting rate.
        Returns:
        resting period for server.

      • genCustomerType

        double genCustomerType()
        Generate a random number between 0 and 1 to determine the type of customer.
        Returns:
        a random number uniformed drawn from 0 to 1.