Class MergeSort<T extends java.lang.Comparable<? super T>>

java.lang.Object

TestTimes

MergeSort<T>

All Implemented Interfaces:

SortInterface<T>, TestTimesInterface

public class MergeSort<T extends java.lang.Comparable<? super T>>
extends TestTimes
implements SortInterface<T>

Nested Class Summary

Nested classes/interfaces inherited from interface TestTimesInterface

TestTimesInterface.MemoryUnits, TestTimesInterface.TimeUnits

Constructor Summary

Constructors

Constructor and Description
MergeSort()

Method Summary

Modifier and Type	Method and Description
private void	merge(T[] array, java.lang.Object[] tempArray, int first, int mid, int last) This method is called to merge two portions of array that are already in sorted order.
private void	mergesort(T[] array, java.lang.Object[] tempArray, int first, int last) This is the recursive method that does the merge sort of array, which has Objects of type T.
void	sort(T[] arrayToSort) This is the method that users will call to sort the specified array of Objects of type T.

Methods inherited from class TestTimes

addTestTime, getAverageMemoryUsage, getAverageTestTime, getLastMemoryUsage, getLastTestTime, getMemoryUnits, getMemoryUsages, getTestTimes, getTimeUnits, resetTestTimes, setMemoryUnits, setTimeUnits

Methods inherited from class java.lang.Object

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

Constructor Detail

MergeSort

public MergeSort()

Method Detail

sort

public void sort(T[] arrayToSort)

This is the method that users will call to sort the specified array of Objects of type T.

This method creates a tempArray and initializes it to contain arrayToSort.size() null elements.

This method will call the mergesort method to perform the recursive sort.

The Comparable interface must either be implemented by T or a superclass of T.

When this method is done, the specified array is sorted.

This method will measure the runtime of the sort and add it to the RunTime class.

Specified by:

sort in interface SortInterface<T extends java.lang.Comparable<? super T>>

Parameters:

arrayToSort - The array of Objects of type T to be sorted.

mergesort

private void mergesort(T[] array,
                       java.lang.Object[] tempArray,
                       int first,
                       int last)

This is the recursive method that does the merge sort of array, which has Objects of type T.

Parameters:

array - The array of Objects of type T to be sorted

tempArray - The temporary array of Objects used in the merge

first - Index of the first entry of the array

last - Index of the last entry of the array

merge

private void merge(T[] array,
                   java.lang.Object[] tempArray,
                   int first,
                   int mid,
                   int last)

This method is called to merge two portions of array that are already in sorted order. The indices of these portions are specified by first, mid and last. All the elements of array are Objects of type T.

The merge operation first merges all the elements in proper sorted order from the two portions of array into tempArray. When the merge is complete, all the elements are then copied back into array.

Parameters:

array - The array of Objects of type T to be sorted

tempArray - The temporary array of Objects used in the merge

first - The index of the beginning of the first section of array to be merged.

mid - The index of the end of the first section of array to be merged.

last - The index of the end of the second section of array to be merged. Please note that the index of the beginning of the second section of array to be merged is at index = mid + 1