Arrays asList() Method in Java with Examples

The Arrays.asList() method in Java is part of the java.util.Arrays class, which is used to convert an array into a fixed-size list. 

• Mainly used to get a List view a given array.
• Note that the list returned and the original array share the same memory. It only gives a list. As we can see in the below program, a change made in the array also reflects in the list.
• Acts as a bridge between array-based and collection-based APIs, in combination with Collection.toArray() which does the opposite.

[1, 2, 3, 4, 5]
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Syntax

public static <T> List<T> asList(T... a)

Parameters:

• "T... a" is an array of elements to be converted into a List.
• The "..." indicates that this is a varargs parameter and it allows multiple elements of type T to be passed as an array.

Return Value:List<T>: This method returns a fixed-size list that contains elements of the same type as the array elements.

Examples of Using the asList() Method in Java

Example: Using asList() Method with String Array

[A, B, C, D]

Example: Using asList() Method with Integer Array

[10, 20, 30, 40]

Example: UnsupportedOperationException with asList()

Exception thrown: java.lang.UnsupportedOperationException

Note: The code compiles successfully, but modifying the list (using add() or remove()) throws a UnsupportedOperationException at runtime because the list is fixed-size

Output: