Java Arrays 二分查找 Int 索引

package com.codingdict;

import java.util.Arrays;

public class ArrayDemo {
   public static void main(String[] args) {

      // initializing unsorted int array
      int intArr[] = {30,20,5,12,55};

      // sorting array
      Arrays.sort(intArr);

      // let us print all the elements available in list
      System.out.println("The sorted int array is:");
      for (int number : intArr) {
         System.out.println("Number = " + number);
      }

      // entering the value to be searched
      int searchVal = 12;

      // entering range of index
      int retVal = Arrays.binarySearch(intArr,1,3,searchVal);

      System.out.println("The index of element 12 is : " + retVal);
   }
}