Discuss the various methods provided by the Array class in Java. Illustrate the usage of these methods with a suitable example program.
Answer:-
Arrays Class in Java
The Arrays class belongs to the java.util package and provides utility methods to work with arrays (like sorting, searching, copying, etc.).
Common Methods of Arrays Class
| Method | Description |
|---|---|
sort(array) | Sorts the array in ascending order |
sort(array, Collections.reverseOrder()) | Sorts in descending order (for object arrays) |
binarySearch(array, key) | Searches the array (must be sorted first) |
copyOf(array, newLength) | Copies array to a new array of specified length |
copyOfRange(array, from, to) | Copies a specific range from the array |
equals(array1, array2) | Checks if two arrays are equal |
fill(array, value) | Fills entire array with a specified value |
toString(array) | Converts array to string (for printing) |
Example Program Using Arrays Class Methods
import java.util.Arrays;
public class ArraysClassDemo {
public static void main(String[] args) {
int[] numbers = {5, 2, 8, 1, 9};
// Print original array
System.out.println("Original Array: " + Arrays.toString(numbers));
// Sort array
Arrays.sort(numbers);
System.out.println("Sorted Array: " + Arrays.toString(numbers));
// Binary Search for 8
int index = Arrays.binarySearch(numbers, 8);
System.out.println("Index of 8: " + index);
// Copy array
int[] copy = Arrays.copyOf(numbers, 7); // length more than original
System.out.println("Copied Array: " + Arrays.toString(copy));
// Fill an array with 0
Arrays.fill(copy, 5, 7, 0);
System.out.println("After fill(): " + Arrays.toString(copy));
// Check equality
boolean isEqual = Arrays.equals(numbers, copy);
System.out.println("Arrays equal: " + isEqual);
}
}
Output
Original Array: [5, 2, 8, 1, 9] Sorted Array: [1, 2, 5, 8, 9] Index of 8: 3 Copied Array: [1, 2, 5, 8, 9, 0, 0] After fill(): [1, 2, 5, 8, 9, 0, 0] Arrays equal: false