Arrays class:
- Java library class belongs to java.util package.
- Arrays class providing set of method to process array elements.
- Some of the methods as follows.
| static void sort(int[] a) | Sorts the specified array into ascending numerical order. |
| static String toString(int[] a) | Returns a string representation of the contents of the specified array. |
| static <T> List<T> asList(T… a) | Returns a fixed-size list backed by the specified array. |
| static int binarySearch(int[] a, int key) | Searches the specified array of ints for the specified value using the binary search algorithm |
| static int[] copyOfRange(int[] original, int from, int to) | Copies the specified range of the specified array into a new array. |
| static boolean equals(int[] a, int[] a2) | Returns true if the two specified arrays of ints are equal to one another. |
| static void fill(int[] a, int val) | Assigns the specified int value to each element of the specified array of ints. |
Sort array elements and display as String:
| import java.util.Random; import java.util.Arrays; class SortArray { public static void main(String[] args) { Random rand = new Random(); int arr[] = new int[5]; for(int i=0 ; i<5 ; i++){ arr[i] = rand.nextInt(100); } System.out.println(“Before sort : ” + Arrays.toString(arr)); Arrays.sort(arr); System.out.println(“After sort : ” + Arrays.toString(arr)); } } |
Search element using Arrays.binarySearch():
| import java.util.Scanner ; import java.util.Arrays ; class Search { public static void main(String[] args) { Scanner scan = new Scanner(System.in); System.out.print(“Enter array size : “); int n = scan.nextInt(); int arr[ ] = new int[n]; System.out.println(“Enter ” + n + ” values : “); for (int i=0 ; i<n ; i++){ arr[i] = scan.nextInt(); } System.out.print(“Enter element to be searched : “); int key = scan.nextInt(); int result = Arrays.binarySearch(arr,key); if (result < 0) System.out.println(“Element is not found!”); else System.out.println(“Element is found at index : ” + result); } } |