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Array vs. ArrayList in Java
Educative Answers TeamIn Java programming, there are two ways to create an array.
-
Array: Is a simple fixed-size data structure which requires a size at the time of creation. -
ArrayList: Is a dynamic sized data structure which doesn’t require a specific size at the time of initialization.
Array
An Array can contain both primitive data types or objects of a class depending on the definition of the array. But it has a fixed size.
Example
// Importing the required libraries
import java.util.Arrays;
class Array
{
public static void main(String args[])
{
/* ...........Array............. */
// Fixed size.
// Cannot add more than 3 elements.
int[] arr = new int[3];
arr[0] = 5;
arr[1] = 6;
arr[2] = 10;
// Printing
System.out.println(Arrays.toString(arr));
}
}ArrayList
An ArrayList can’t be created for primitive data types. It only contains an object. It has the ability to grow and shrink dynamically.
- Remember that in Java, every primitive data type has a wrapper class.
| Primitive | Wrapper class |
| — | — |
|
int|Integer| |short|Short| |byte|Byte| |char|Character| |float|Float|
Example
// Importing required libraries
import java.util.ArrayList;
class Array_List
{
public static void main(String args[])
{
/*............ArrayList..............*/
// Variable size.
// Can add more elements.
ArrayList<Integer> arr = new ArrayList<Integer>();
arr.add(5);
arr.add(9);
arr.add(11);
// Printing
System.out.println(arr);
}
}RELATED TAGS
array
arraylist
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