How do I convert a collection object into an array?

To convert collection-based data into array we can use toArray() or toArray(T[] a) method provided by the implementation of Collection interface such as java.util.ArrayList.

package org.kodejava.example.util;

import java.util.List;
import java.util.ArrayList;

public class CollectionToArrayExample {
    public static void main(String[] args) {
        List<String> words = new ArrayList<>();
        words.add("Kode");
        words.add("Java");
        words.add("Sample");
        words.add("Code");

        String[] array = words.toArray(new String[words.size()]);
        for (String word : array) {
            System.out.println(word);
        }
    }
}

Our sample code result is shown below:

Kode
Java
Sample
Code

Wayan Saryada

Programmer, runner, recreational diver, currently living in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, Hibernate / JPA.

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