Question

What is integer boxing in java

Answer 1

In Java the boxing range for any integer is between -128 and 127. So whenever you use numbers in this specified range, you can compare it with the “==” operator. But for Integer objects outside the range you can only use equals.

Autoboxing in Java is converting a primitive value into an object of the corresponding wrapper class eg. Converting int to integer class.

Unboxing in Java refers to converting an object of a wrapper type to its corresponding primitive value eg. Conversion of Integer to int.

Here is an illustration of autoboxing and unboxing:

1.        import java.io.*;
2.        import java.util.*;
3.        class Integer_Boxing
4.        {
5.        public static void main (String[] args)
6.        {
7.        List<Integer> list = new ArrayList<Integer>();
      for (int i = 0; i < 10; i++)
9.        list.add(i);
10.     }
11.     }

In the above example we are including int primitive types rather than Integer Object.

Hope this helps!!