Split or move core-java-collections module (#7893)

core-java-modules/core-java-arrays-2/README.MD

@@ -7,3 +7,4 @@
 - [Array Operations in Java](https://www.baeldung.com/java-common-array-operations)
 - [Intersection Between two Integer Arrays](https://www.baeldung.com/java-array-intersection)
 - [Removing an Element from an Array in Java](https://www.baeldung.com/java-array-remove-element)
+- [Removing the First Element of an Array](https://www.baeldung.com/java-array-remove-first-element)

core-java-modules/core-java-arrays-2/src/test/java/com/baeldung/array/removefirst/RemoveFirstElementUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.array.removefirst;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class RemoveFirstElementUnitTest {
+
+    private List<String> list = new ArrayList<>();
+    private LinkedList<String> linkedList = new LinkedList<>();
+
+    @Before
+    public void init() {
+
+        list.add("cat");
+        list.add("dog");
+        list.add("pig");
+        list.add("cow");
+        list.add("goat");
+
+        linkedList.add("cat");
+        linkedList.add("dog");
+        linkedList.add("pig");
+        linkedList.add("cow");
+        linkedList.add("goat");
+    }
+
+    @Test
+    public void givenList_whenRemoveFirst_thenRemoved() {
+        list.remove(0);
+
+        assertThat(list, hasSize(4));
+        assertThat(list, not(contains("cat")));
+    }
+
+    @Test
+    public void givenLinkedList_whenRemoveFirst_thenRemoved() {
+
+        linkedList.removeFirst();
+
+        assertThat(linkedList, hasSize(4));
+        assertThat(linkedList, not(contains("cat")));
+    }
+
+    @Test
+    public void givenStringArray_whenRemovingFirstElement_thenArrayIsSmallerAndElementRemoved() {
+        String[] stringArray = {"foo", "bar", "baz"};
+
+        String[] modifiedArray = Arrays.copyOfRange(stringArray, 1, stringArray.length);
+
+        assertThat(modifiedArray.length, is(2));
+        assertThat(modifiedArray[0], is("bar"));
+    }
+
+}