Interface TestTimesInterface

public interface TestTimesInterface

This interface will be used to organize and manage test times that are measured for specific operations. Implementing this interface requires the following:

• The implementation is required to save the last 10 time measurements. If the user adds exactly 10 measurements, the implementation will keep all 10. If the user adds n, where n > 10, the implementation will keep the last 10 measurements.
• If you have made no measurements, your array will contain the following: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0].
• If you have made 5 measurements m_n, your array will contain the following: [m₁, m₂, m₃, m₄, m₅, 0, 0, 0, 0, 0].
• If you have made 10 measurements m_n, your array will contain the following: [m₁, m₂, m₃, m₄, m₅, m₆, m₇, m₈, m₉, m₁₀].
• If you have made 13 measurements m_n, your array will contain the following: [m₄, m₅, m₆, m₇, m₈, m₉, m₁₀, m₁₁, m₁₂, m₁₃].
• Please pay attention to the ordering of the measurements described above.
• The implementation is required to compute average calculations using only added measurements.
• If the user has added only 3 measurements m_n, then the average is (m₁ + m₂ + m₃)/3.
• If the user has added 10 measurements, then the average is (m₁ + m₂ + m₃ + m₄ + m₅ + m₆ + m₇ + m₈ + m₉ + m₁₀)/10.
• If the user has added n measurement, where n > 10, then the average is (m_n-9 + m_n-8 + m_n-7 + m_n-6 + m_n-5 + m_n-4 + m_n-3 + m_n-2 + m_n-1 + m_n)/10.
• The implementation will represent all nanosecond time measurements as long values.
• The implementation will compute averages and represent them as double values.

Users of an implementation of this interface calculate time measurements as follows:

• Before the operation is started, you can obtain the start time:
  long startTime = System.nanoTime().
• After the operation is completed, you can obtain the end time:
  long endTime = System.nanoTime().
• Test Time can then be computed:
  long testTime = endTime - startTime.

Author:

Sameh A. Fakhouri

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	TestTimesInterface.MemoryUnits Memory usage is measured in Bytes.
static class	TestTimesInterface.TimeUnits Run times are measured in Nano Seconds.

Method Summary

Modifier and Type	Method and Description
void	addTestTime(long runTime) This method is used to add a test time and capture the current memory usage.
double	getAverageMemoryUsage() This method is used to obtain the average memory usage.
double	getAverageTestTime() This method is used to obtain the average test time.
double	getLastMemoryUsage() This method is used to retrieve the last memory usage.
double	getLastTestTime() This method is used to retrieve the last test time.
TestTimesInterface.MemoryUnits	getMemoryUnits() This method is used to obtain the current TestTimesInterface.MemoryUnits configured for the RunTime class.
double[]	getMemoryUsages() This method returns an array of double values representing the last 10 memory usages converted to the configured TestTimesInterface.MemoryUnits.
double[]	getTestTimes() This method returns an array of double values representing the last 10 test times converted to the configured TestTimesInterface.TimeUnits.
TestTimesInterface.TimeUnits	getTimeUnits() This method is used to obtain the current TestTimesInterface.TimeUnits configured for the RunTime class.
void	resetTestTimes() This method is used to reset all 10 linear search times to zero.
void	setMemoryUnits(TestTimesInterface.MemoryUnits memoryUnits) This method is used to configure the desired TestTimesInterface.MemoryUnits.
void	setTimeUnits(TestTimesInterface.TimeUnits timeUnits) This method is used to configure the desired TestTimesInterface.TimeUnits.

Method Detail

getTimeUnits

TestTimesInterface.TimeUnits getTimeUnits()

This method is used to obtain the current TestTimesInterface.TimeUnits configured for the RunTime class. Please note that the default TimeUnits is NanoSeconds

Returns:

The currently configured TimeUnits.

setTimeUnits

void setTimeUnits(TestTimesInterface.TimeUnits timeUnits)

This method is used to configure the desired TestTimesInterface.TimeUnits.

Parameters:

timeUnits - The desired TimeUnits

getMemoryUnits

TestTimesInterface.MemoryUnits getMemoryUnits()

This method is used to obtain the current TestTimesInterface.MemoryUnits configured for the RunTime class. Please note that the default MemoryUnits is Bytes

Returns:

The currently configured MemoryUnits.

setMemoryUnits

void setMemoryUnits(TestTimesInterface.MemoryUnits memoryUnits)

This method is used to configure the desired TestTimesInterface.MemoryUnits.

Parameters:

memoryUnits - The desired MemoryUnits

getLastTestTime

double getLastTestTime()

This method is used to retrieve the last test time. If no test time has been added, the method will return a zero.

Returns:

The last test time, converted to the configured TestTimesInterface.TimeUnits, or 0.

getLastMemoryUsage

double getLastMemoryUsage()

This method is used to retrieve the last memory usage. If no test time has been added, the method will return a zero.

Returns:

The last memory usage, converted to the configured TestTimesInterface.MemoryUnits, or 0.0.

getTestTimes

double[] getTestTimes()

This method returns an array of double values representing the last 10 test times converted to the configured TestTimesInterface.TimeUnits. If less than 10 test times are available, the remaining test times should be zero. If more than 10 test times have been added, the array should contain the last 10 test times.

Returns:

An array of double values representing the last 10 test times.

getMemoryUsages

double[] getMemoryUsages()

This method returns an array of double values representing the last 10 memory usages converted to the configured TestTimesInterface.MemoryUnits. If less than 10 memory usages are available, the remaining memory usages should be zero. If more than 10 memory usages have been added, the array should contain the last 10 memory usages.

Returns:

An array of double values representing the last 10 memory usages.

resetTestTimes

void resetTestTimes()

This method is used to reset all 10 linear search times to zero.

addTestTime

void addTestTime(long runTime)

This method is used to add a test time and capture the current memory usage.

Parameters:

runTime - a long value representing the test time in nanoseconds.

getAverageTestTime

double getAverageTestTime()

This method is used to obtain the average test time. The method should average all the non-zero test times that are available. If no test times are available, the method returns a zero.

Returns:

A double value representing the average of all the non-zero test times, converted to the configured TestTimesInterface.TimeUnits or 0.

getAverageMemoryUsage

double getAverageMemoryUsage()

This method is used to obtain the average memory usage. The method should average all the non-zero memory usages that are available. If no memory usages are available, the method returns a zero.

Returns:

A double value representing the average of all the non-zero memory usages, converted to the configured TestTimesInterface.MemoryUnits, or 0.0.