Java data Sturcture Searching and Sorting

/** A class of static methods for searching an array of Comparable objects. @author Frank M. Carrano @author Timothy M. Henry @version 4.0 */ public class ArraySearcher { // Segment 18.3 /** Searches an unsorted array for anEntry. */ public static <T> boolean inArrayIterativeUnsorted(T[] anArray, T anEntry) { boolean found = false; int index = 0; while (!found && (index < anArray.length)) { if (anEntry.equals(anArray[index])) found = true; index++; } // end while return found; } // end inArrayIterativeUnsorted // ======================================================================================== // Segment 18.6 /** Searches an unsorted array for anEntry. */ public static <T> boolean inArrayRecursiveUnsorted(T[] anArray, T anEntry) { return search(anArray, 0, anArray.length - 1, anEntry); } // end inArrayRecursiveUnsorted // Searches anArray[first] through anArray[last] for desiredItem. // first >= 0 and < anArray.length. // last >= 0 and < anArray.length. private static <T> boolean search(T[] anArray, int first, int last, T desiredItem) { boolean found = false; if (first > last) found = false; // No elements to search else if (desiredItem.equals(anArray[first])) found = true; else found = search(anArray, first + 1, last, desiredItem); return found; } // end search // ======================================================================================== /** Searches a sorted array for anEntry. */ public static <T extends Comparable<? super T>> boolean inArrayRecursiveSorted(T[] anArray, T anEntry) { return binarySearch(anArray, 0, anArray.length - 1, anEntry); } // end inArrayRecursiveSorted // Segment 18.13 // Searches anArray[first] through anArray[last] for desiredItem. // first >= 0 and < anArray.length. // last >= 0 and < anArray.length. private static <T extends Comparable<? super T>> boolean binarySearch(T[] anArray, int first, int last, T desiredItem) { boolean found; int mid = first + (last - first) / 2; if (first > last) found = false; else if (desiredItem.equals(anArray[mid])) found = true; else if (desiredItem.compareTo(anArray[mid]) < 0) found = binarySearch(anArray, first, mid - 1, desiredItem); else found = binarySearch(anArray, mid + 1, last, desiredItem); return found; } // end binarySearch // ======================================================================================== public static <T> void display(T[] anArray) { System.out.print("The array contains the following entries: "); for (int index = 0; index < anArray.length; index++) { System.out.print(anArray[index] + " "); } // end for System.out.println(); } // end display } // end ArraySearcher