Java Examples - Array sort and insert

Problem Description

How to sort an array and insert an element inside it?

Solution

Following example shows how to use sort () method and user defined method insertElement ()to accomplish the task.

import java.util.Arrays;

public class MainClass {
   public static void main(String args[]) throws Exception {
      int array[] = { 2, 5, -2, 6, -3, 8, 0, -7, -9, 4 };
      Arrays.sort(array);
      printArray("Sorted array", array);
      
      int index = Arrays.binarySearch(array, 1);
      System.out.println("Didn't find 1 @ " + index);
      
      int newIndex = -index - 1;
      array = insertElement(array, 1, newIndex);
      printArray("With 1 added", array);
   }
   private static void printArray(String message, int array[]) {
      System.out.println(message + ": [length: " + array.length + "]");
      for (int i = 0; i < array.length; i++) {
         if (i != 0){
            System.out.print(", ");
         }
         System.out.print(array[i]);         
      }
      System.out.println();
   }
   private static int[] insertElement(int original[], int element, int index) {
      int length = original.length;
      int destination[] = new int[length + 1];
      System.arraycopy(original, 0, destination, 0, index);
      destination[index] = element;
      System.arraycopy(original, index, destination, index + 1, length - index);
      return destination;
   }
}

Result

The above code sample will produce the following result.

Sorted array: [length: 10]
-9, -7, -3, -2, 0, 2, 4, 5, 6, 8
Didn't find 1 @ -6
With 1 added: [length: 11]
-9, -7, -3, -2, 0, 1, 2, 4, 5, 6, 8