ptolemy.actor.util.test

Class DoubleCQComparator

java.lang.Object

ptolemy.actor.util.test.DoubleCQComparator

All Implemented Interfaces:

java.util.Comparator, CQComparator

public class DoubleCQComparator
extends java.lang.Object
implements CQComparator

This class implements the CQComparator interface. It compares instances of Double. Therefore, all arguments passed to its methods have to be of type Double (or Double[] for the getBinWidth() method). If this is violated, a ClassCastException will be thrown. This class is used to test the CalendarQueue.

Since:

Ptolemy II 0.2

Author:

Lukito Muliadi

See Also:

CQComparator, CalendarQueue

Pt.AcceptedRating:

Yellow (liuj)

Pt.ProposedRating:

Green (eal)

Constructor Summary

Constructors

Constructor and Description
DoubleCQComparator()

Method Summary

Modifier and Type	Method and Description
int	compare(java.lang.Object object1, java.lang.Object object2) Compare the two argument.
long	getVirtualBinNumber(java.lang.Object entry) Given an entry, a zero reference, and a bin width, return a virtual bin number for the entry.
void	setBinWidth(java.lang.Object[] entryArray) Given an array of Double objects, find the appropriate bin width.
void	setZeroReference(java.lang.Object zeroReference) Set the zero reference, to be used in calculating the virtual bin number.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

DoubleCQComparator

public DoubleCQComparator()

Method Detail

compare

public int compare(java.lang.Object object1,
                   java.lang.Object object2)

Compare the two argument. Return a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second. Both arguments have to be instances of Double, otherwise a ClassCastException will be thrown.

Specified by:

compare in interface java.util.Comparator

Parameters:

object1 - The first Double.

object2 - The second Double.

Returns:

A negative integer, zero, or a positive integer if the first argument is less than, equal to, or greater than the second.

Throws:

java.lang.ClassCastException - If either argument is not an instance of Double.

getVirtualBinNumber

public long getVirtualBinNumber(java.lang.Object entry)

Given an entry, a zero reference, and a bin width, return a virtual bin number for the entry. The virtual bin number is a quantized double. The calculation performed is:

(entry - zeroReference) / binWidth,

with the result cast to long. If the arguments are not instances of Double, then a ClassCastException will be thrown.

Specified by:

getVirtualBinNumber in interface CQComparator

Parameters:

entry - The entry.

Returns:

The virtual bin number for the entry, according to the zero reference and the bin width.

Throws:

java.lang.ClassCastException - If the arguments are not instances of Double.

setBinWidth

public void setBinWidth(java.lang.Object[] entryArray)

Given an array of Double objects, find the appropriate bin width. By 'appropriate', the bin width is chosen such that on average the number of entry in all non-empty bins is equal to one. If the argument is null, return the default bin width, which is 1.0 for this implementation.

Specified by:

setBinWidth in interface CQComparator

Parameters:

entryArray - An array of Double objects.

Throws:

java.lang.ClassCastException - If one of the array elements is not an instance of Double.

setZeroReference

public void setZeroReference(java.lang.Object zeroReference)

Set the zero reference, to be used in calculating the virtual bin number.

Specified by:

setZeroReference in interface CQComparator

Parameters:

zeroReference - The starting point for bins.

Throws:

java.lang.ClassCastException - If the argument is not an instance of Double.