Create List containing n Copies of Specified Object in Java

To create a Java List containing n Copies of a specified Object, nCopies() method of java.util.Collections class can be used. The nCopies() method takes two parameters – n the length of the list and the object which has to be copied n times in the list.

Example:

Input : n = 4, Object = "Hello"
Output: listOfObjects = ["Hello", "Hello", "Hello", "Hello"]

Input : n = 3, Object = 3
Output: listOfObjects = [3, 3, 3]

Declaration:

public static nCopies(int length, Object object)

Return Value: An immutable List containing n copies of the specified object.

Exception Throws: IllegalArgumentException
if the length provided is less than 0
i.e, n < 0

Java

// Create List containing n Copies
// of Specified Object in java
import java.io.*;
import java.util.Collections;
import java.util.List;

class GFG {
    public static void main(String[] args)
    {
        int n = 5;
        Object myObj = "GFG";

        List myList = Collections.nCopies(n, myObj);

        System.out.println(myList);
    }
}

Output

[GFG, GFG, GFG, GFG, GFG]