Collections.singletonList("Hello") returns an immutable list containing exactly one specified element | Java collection

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Collections.singletonList("Hello") returns an immutable list containing exactly one specified item | Java collection

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обновлено: 12 September 2026

Java

List<String> myList = Collections.singletonList("Hello");
// myList has 1 element
// myList[0] = "Hello"

Collections.singletonList returns an immutable list containing exactly one specified item.
Attempts to add, remove, or replace items in such a list will result in a UnsupportedOperationException exception.

Complete example

Java Creating a new Java console application ... and write the code

import java.util.Collections;
import java.util.List;

public class Main {
     public static void main(String[] args) {

          List<String> myList = Collections.singletonList("Hello");
     }
}

Additionally

class Collections
all the functions ...

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