How to search element in Byte Array using Index in Java?

Declaration :

public static int binarySearch(byte[] a, int fromIndex, int toIndex, byte key)

1	public static int binarySearch(byte[] a, int fromIndex, int toIndex, byte key)

Explanation :

Purpose	The java.util.Arrays.binarySearch(byte[] a int fromIndex int toIndex byte key) method searches a range of the specified array of bytes for the specified value using the binary search algorithm. The range must be sorted before making this call.If it is not sorted the results are undefined.
Parameters	a ===> This is the array to be searched.
	fromIndex ===> This is the index of the first element (inclusive) to be searched.
	toIndex ===> This is the index of the last element (exclusive) to be searched.
	key ===> This is the value to be searched for.
Return Value	This method returns index of the search key if it is contained in the array else it returns (-(insertion point) - 1). The insertion point is the point at which the key would be inserted into the array; the index of the first element in the range greater than the key or toIndex if all elements in the range are less than the specified key.
Exception	IllegalArgumentException — if fromIndex > toIndex ,ArrayIndexOutOfBoundsException — if fromIndex < 0 or toIndex > a.length

Java Program : Example

Below example will explain java.util.Arrays.binarySearch() method.

package com.c4learn;
import java.util.Arrays;
public class ArrayDemo {
   public static void main(String[] args) {
    // Initialize unsorted byte array
    byte arr[] = {10,20,50,30,40};
    // Sorting array
    Arrays.sort(arr);
    // Printing sorted Array list
    System.out.println("The sorted byte array is:");
    for (byte number : arr) {
      System.out.println("Element = " + number);
    }
    // Value to be searched
    byte searchVal = 30;
    // Entering the range of index
    int retVal = Arrays.binarySearch(arr,0,5,searchVal);
    System.out.println("The index of element 30 is : " + retVal);
  }
}

package com.c4learn;

import java.util.Arrays;

public class ArrayDemo {

public static void main(String[] args) {

// Initialize unsorted byte array

byte arr[] = {10,20,50,30,40};

// Sorting array

Arrays.sort(arr);

// Printing sorted Array list

System.out.println("The sorted byte array is:");

for (byte number : arr) {

System.out.println("Element = " + number);

}

// Value to be searched

byte searchVal = 30;

// Entering the range of index

int retVal = Arrays.binarySearch(arr,0,5,searchVal);

System.out.println("The index of element 30 is : " + retVal);

}

Output of Program :

The sorted byte array is:
Element = 10
Element = 20
Element = 30
Element = 40
Element = 50
The index of element 30 is : 2

The sorted byte array is:

Element = 10

Element = 20

Element = 30

Element = 40

Element = 50

The index of element 30 is : 2

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