Java data Sturcture Searching and Sorting

import java.util.* ; public class SortArray { public static <T extends Comparable<? super T>> void selectionSort(T[] a, int n) { for (int index = 0; index < n - 1; index++) { int indexOfSmallest = indexOfSmallest(a, index, n - 1); T temp = a[index]; a[index] = a[indexOfSmallest]; a[indexOfSmallest] = temp; //Invariant: a[0] <= a[1] <= . . . <= a[index] <= all other a[i] } // end for } // end selectionSort private static <T extends Comparable<? super T>> int indexOfSmallest(T[] a, int first, int last) { T min = a[first]; int indexOfMin = first; for (int index = first + 1; index <= last; index++) { if (a[index].compareTo(min) < 0) { min = a[index]; indexOfMin = index; } } return indexOfMin; } public static <T extends Comparable<? super T>> void insertionSort(T[] a, int n) { for(int unsorted = 1; unsorted < n; ++unsorted) { T item = a[unsorted]; int loc = unsorted; while(loc > 0 && a[loc-1].compareTo(item) > 0) { a[loc] = a[loc-1]; --loc; } a[loc] = item; } } public static <T extends Comparable<? super T>> void bubbleSort(T[] a, int n) { for(int pass = 1; pass < n ; ++pass) { for(int index = 0; index < n-pass; ++index) { int nextIndex = index + 1; if(a[index].compareTo(a[nextIndex]) > 0) { T temp = a[index]; a[index] = a[nextIndex]; a[nextIndex] = temp; } } } } public static <T extends Comparable<? super T>> void bubbleSort2(T[] a, int n) { boolean sorted = false; for(int pass = 1; pass < n && !sorted ; ++pass) { sorted = true; for(int index = 0; index < n-pass; ++index) { int nextIndex = index + 1; if(a[index].compareTo(a[nextIndex]) > 0) { T temp = a[index]; a[index] = a[nextIndex]; a[nextIndex] = temp; sorted = false; } } } } public static void main(String [] args) { Integer [] a = { 15, 8 , 10 , 2, 5 }; //selectionSort(a, a.length); //insertionSort(a, a.length); //bubbleSort(a, a.length); bubbleSort2(a, a.length); System.out.println("a = " + Arrays.toString(a)); } } // end SortArray