implementation eugenp#8268 (eugenp#17046)

* implementation eugenp#8268

* pr-feedbacks

---------

Co-authored-by: technoddy <mail.technoddy@gmail.com>

Author: imsurajmishra

core-java-modules/core-java-collections-list-4/src/test/java/com/baeldung/list/addelementatindex/AddElementAtIndexUnitTest.java

@@ -3,11 +3,12 @@
 import org.junit.jupiter.api.Test;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
+import java.util.Collections;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-
 class AddElementAtIndexUnitTest {
 
     @Test
@@ -37,4 +38,28 @@ void givenArrayList_whenAddElementAtIndex_thenGetExpectedElementAtIndex() {
         assertThat(integers.get(3)).isEqualTo(8);
         assertThat(integers.get(4)).isEqualTo(9);
     }
+
+    @Test
+    void givenArrayList_whenAddElementsAtTheBeginningWithAddMethod_thenAddsElementAtTheBeginning() {
+        List<Integer> integers = new ArrayList<>();
+        integers.addAll(Arrays.asList(4, 5, 6, 7));
+        int existingSize = integers.size();
+
+        integers.add(0, 3);
+        assertThat(integers.get(0)).isEqualTo(3);
+        assertThat(integers.size()).isEqualTo(existingSize + 1);
+    }
+
+    @Test
+    void givenArrayList_whenAddElementsAtTheBeginningWithCollectionsReverse_thenAddsElementAtTheBeginning() {
+        List<Integer> integers = new ArrayList<>();
+        integers.addAll(Arrays.asList(4, 5, 6, 7));
+        int existingSize = integers.size();
+
+        Collections.reverse(integers);
+        integers.add(1);
+        Collections.reverse(integers);
+        assertThat(integers.get(0)).isEqualTo(1);
+        assertThat(integers.size()).isEqualTo(existingSize + 1);
+    }
 }