unl.cusack.estimator
Class EstimatorModel

java.lang.Object
  |
  +--unl.cusack.estimator.EstimatorModel

Direct Known Subclasses:

PiEstimatorModel

public abstract class EstimatorModel

extends java.lang.Object

The EstimatorModel is the model of an estimator. It is an abstract class, leaving the details of the estimator to the subclasses. The model assumes there is a formula f(i) to compute the ith estimate of the number to be estimated. The model stores the first index which is desired, the number of estimates to store, and the interval between intervals. For instance, if

numberOfEstimates=4

firstEstimate=3

estimateInterval=5 then the model will store f(3), f(8), f(13), and f(18).

The model maintains a list of object which are registered as listeners to this class. If the model changes, this class will inform each of the registered listeners of the fact that the model has changed, leavinf it up to each of them what they want to do about it.

Field Summary

protected double[]	estimates
protected java.util.Set	estimatorListeners

Constructor Summary

EstimatorModel()
The constructor, assuming an empty model

Method Summary

void	addEstimatorListener(EstimatorListener listener) Add a listener the the list
void	dataChanged() If any of the data in the model changes, this method takes care of recalculating the estimates, and informing the listeners of the fact that the model has changed.
double	getEstimate(int n) Get the nth estimate from the list
int	getEstimatorInterval()
int	getFirstEstimate() Get the index of the first stored estimate
double	getMaximumEstimate()
double	getMinimumEstimate()
int	getNumberOfEstimates()
abstract void	recalculateEstimates()
void	setEstimateInterval(int n) Set the desired interval between estimates to n
void	setFirstEstimate(int n) Set the index of the first estimate to n
void	setNumberOfEstimates(int n) Sets the number of estimates to n
void	setParameters(int n, int f, int i) Set all of the parameters of the model

Methods inherited from class java.lang.Object

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

Field Detail

estimates

protected double[] estimates

estimatorListeners

protected java.util.Set estimatorListeners

Constructor Detail

EstimatorModel

public EstimatorModel()

The constructor, assuming an empty model

Method Detail

recalculateEstimates

public abstract void recalculateEstimates()

getEstimate

public double getEstimate(int n)

Get the nth estimate from the list

Parameters:

n - the index of the desired estimate Note: This is asking for the nth estimate that is stored in the model, not f(n), where f is the function that computes the estimates.

Returns:

the nth estimate on the list. If n is not between 0 and numberOfEstimates, it returns 0. It should really throw and exception, but for simplicity, and since the point of the example is to demostrate MVC, not exception handling, simple is better.

getMaximumEstimate

public double getMaximumEstimate()

Returns:

the maximum of the stored estimates

getMinimumEstimate

public double getMinimumEstimate()

getNumberOfEstimates

public int getNumberOfEstimates()

Returns:

the number of stored estimates

setNumberOfEstimates

public void setNumberOfEstimates(int n)

Sets the number of estimates to n

Parameters:

n - the number of desired estimates

getFirstEstimate

public int getFirstEstimate()

Get the index of the first stored estimate

Returns:

the index of the first estimate

setFirstEstimate

public void setFirstEstimate(int n)

Set the index of the first estimate to n

Parameters:

n - the desired index of the first estimate

getEstimatorInterval

public int getEstimatorInterval()

Returns:

the interval between estimates

setEstimateInterval

public void setEstimateInterval(int n)

Set the desired interval between estimates to n

Parameters:

n - the desried interval between estimates.

setParameters

public void setParameters(int n,
                          int f,
                          int i)

Set all of the parameters of the model

Parameters:

n - desired number of estimates

f - desired index of first index

i - desired interval between estimates

addEstimatorListener

public void addEstimatorListener(EstimatorListener listener)

Add a listener the the list

Parameters:

listener - the object desiring to listen to this class

dataChanged

public void dataChanged()

If any of the data in the model changes, this method takes care of recalculating the estimates, and informing the listeners of the fact that the model has changed.