package com.baeldung.toarraymethod; import org.junit.Test; import java.util.HashSet; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertTrue; public class ConvertingHashSetToArrayUnitTest { @Test public void givenStringHashSet_whenConvertedToArray_thenArrayContainsStringElements() { HashSet stringSet = new HashSet<>(); stringSet.add("Apple"); stringSet.add("Banana"); stringSet.add("Cherry"); // Convert the HashSet of Strings to an array of Strings String[] stringArray = stringSet.toArray(new String[0]); // Test that the array is of the correct length assertEquals(3, stringArray.length); for (String str : stringArray) { assertTrue(stringSet.contains(str)); } } @Test public void givenIntegerHashSet_whenConvertedToArray_thenArrayContainsIntegerElements() { HashSet integerSet = new HashSet<>(); integerSet.add(5); integerSet.add(10); integerSet.add(15); // Convert the HashSet of Integers to an array of Integers Integer[] integerArray = integerSet.toArray(new Integer[0]); // Test that the array is of the correct length assertEquals(3, integerArray.length); for (Integer num : integerArray) { assertTrue(integerSet.contains(num)); } assertTrue(integerSet.contains(5)); assertTrue(integerSet.contains(10)); assertTrue(integerSet.contains(15)); } }