Answer :
Answer:
You would have to recreate the array as a larger size.
Explanation:
What is an Array?
An array is a data structure that consists of multiple elements of the same type.
An array could be of any type and store any value (as long as it's of the same type the array was declared with). An example of this is an array called nums of the integers 1, 2, 3, 4 and 5. We would declare it as so:
int[] nums = {1, 2, 3, 4, 5};
How is an Array Stored in Memory?
An array is not stored in the same way as an integer, for example.
Integers, doubles, chars, they all have a fixed size in memory. Integers, for example, will always be stored using 4 bytes (32 bits) in memory. It's easy for your computer to allocate memory for a data type whose size it's already aware of.
With arrays, on the other hand, Java can't know in advance how many elements your array is gonna have. It can't reserve an unknown amount of bytes in memory.
So how do we store arrays in memory? Well, we already know the size of the data type that all of the elements in the array share, so we can simply store them adjacently to one another in memory.
Let's say we want to store our array, nums, in memory. To do this, Java finds a random place in memory, let's say with the address 1000, and allocates all of the array's elements there adjacently:
- The first element, 1, is gonna take up addresses 1000-1003
- The second element, 2, is gonna take up addresses 1004-1007
- The third, 3, 1008-1011
- The fourth, 4, 1012-1015
- And finally, 5, 1016-1019
The value stored within the variable nums is the address of the first element's location in memory (in this case, 1000).
And so, if we want to select the 3rd element of the array, we simply have to jump 4 bytes 2 times from the address of the first element in array. Most programming languages use the notation array[index], where index is the amount of times you want to jump ahead. In our case, we want to select the 3rd element from the nums array so our index is 2 (1000 + 4 + 4 = 1008, the address of the third element).
Why Can't We Resize an Array Dynamically?
Congratulations! You just stored your first array, nums.
But now you decide you want to add another element, 6. No biggies, we know that the address of the last byte of the 5th element of nums is 1019, so we'll just store 6 in the addresses 1020-1023.
But we can't really do that, because we don't know what actually exists between those addresses. For all we know, overriding the value stored within them could cause a major flaw in our program by losing some really important memory. In a lot of programming environments, your program would very luckily crash and you'll be stopped from going through with this request. But imagine the damage if it didn't.
A lot of programming languages, like C++, implement similar data structures like vectors who are dynamic in size. But we should keep in mind while working with arrays that this is not something that can be used.
If you wanted to add an element to the array, you would have to restore it in memory.
It's also recommended that you release the previously occupied memory of the smaller array.
In Java, you cannot expand an array directly; instead, you need to recreate it with a larger size or use a dynamic data structure like ArrayList which supports resizing.
In Java, if you need to expand an array that stores book titles in a library system, you would need to recreate the array with a larger size. Java arrays have a fixed size once they are created, so you cannot dynamically expand an existing array directly.
To handle this, you can create a new array with a larger size and copy the elements from the old array to the new one. Alternatively, you can use a more flexible data structure such as an ArrayList, which allows dynamic resizing.
Example:
import java.util.ArrayList;
