randoop.generation

Class OrienteeringSelection.SequenceDetails

java.lang.Object

randoop.generation.OrienteeringSelection.SequenceDetails

Enclosing class:

OrienteeringSelection

private static class OrienteeringSelection.SequenceDetails
extends java.lang.Object

Information used by Orienteering to compute a weight for a sequence.

Field Summary

Fields

Modifier and Type	Field and Description
private long	executionTimeNanos The execution time of the sequence, in nanoseconds.
private double	methodSizeSqrt The square root of the number of method calls in the sequence.
private int	selectionCount Number of times this sequence has been selected by OrienteeringSelection.
private double	weight A Sequence's weight.

Constructor Summary

Constructors

Constructor and Description
SequenceDetails(double methodSizeSqrt, long executionTimeNanos) Create a SequenceDetails.
SequenceDetails(Sequence sequence, long executionTimeNanos) Create a SequenceDetails for the given sequence, but using the given execution time.

Method Summary

Modifier and Type	Method and Description
double	getWeight() Returns the weight of the sequence.
void	incrementSelectionCount() Increments the selection count.
private void	updateWeight() Compute the weight of a sequence.

Methods inherited from class java.lang.Object

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

Field Detail

methodSizeSqrt

private final double methodSizeSqrt

The square root of the number of method calls in the sequence.

executionTimeNanos

private final long executionTimeNanos

The execution time of the sequence, in nanoseconds.

selectionCount

private int selectionCount

Number of times this sequence has been selected by OrienteeringSelection.

weight

private double weight

A Sequence's weight. This is computed from the other fields and is updated when selectionCount is.

Constructor Detail

SequenceDetails

SequenceDetails(Sequence sequence,
                long executionTimeNanos)

Create a SequenceDetails for the given sequence, but using the given execution time.

Parameters:

sequence - a sequence

executionTimeNanos - execution time in nanoseconds

SequenceDetails

public SequenceDetails(double methodSizeSqrt,
                       long executionTimeNanos)

Create a SequenceDetails.

Parameters:

methodSizeSqrt - the square root of the number of method calls

executionTimeNanos - the execution time, in nanoseconds

Method Detail

incrementSelectionCount

public void incrementSelectionCount()

Increments the selection count.

getWeight

public double getWeight()

Returns the weight of the sequence.

Returns:

the weight of the sequence

updateWeight

private void updateWeight()

Compute the weight of a sequence. The formula for a sequence's weight is:

1.0 / (k * seq.exec_time * sqrt(seq.meth_size))

where k is the number of selections of seq and exec_time is the execution time of seq and meth_size is the number of method call statements in seq. This formula is a slight simplification of the one described in the GRT paper which maintains a separate exec_time for each execution of seq. However, we assume that every execution time for a sequence is the same as the first execution.