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diff --git a/main/src/test/java/org/apache/poi/util/TestArrayUtil.java b/main/src/test/java/org/apache/poi/util/TestArrayUtil.java
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+
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.util;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.Arrays;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Unit test for ArrayUtil
+ */
+class TestArrayUtil {
+	/**
+	 * Helper for testArrayMoveWithin
+	 */
+	private Integer[] getIntsList() {
+		return new Integer[] {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
+	}
+
+	/**
+	 * Test to ensure that arrayMoveWithin works as expected
+	 */
+	@Test
+	void testArrayMoveWithin() {
+		// moveFrom, moveTo, numToMove, values...
+		Integer[][] data = {
+			// Moving to a later point in the array
+			// Shift 1 back
+			{ 4, 8, 1,      0, 1, 2, 3, 5, 6, 7, 8, 4, 9 },
+			// Shift front 1 back
+			{ 0, 7, 1,      1, 2, 3, 4, 5, 6, 7, 0, 8, 9 },
+			// Shift 1 to end
+			{ 4, 9, 1,      0, 1, 2, 3, 5, 6, 7, 8, 9, 4 },
+
+			// Moving to an earlier point in the array
+			// Shift 1 forward
+			{ 8, 3, 1,      0, 1, 2, 8, 3, 4, 5, 6, 7, 9 },
+			// Shift end 1 forward
+			{ 9, 2, 1,      0, 1, 9, 2, 3, 4, 5, 6, 7, 8 },
+			// Shift 1 to front
+			{ 5, 0, 1,      5, 0, 1, 2, 3, 4, 6, 7, 8, 9 },
+
+			// Moving many to a later point in the array
+			// Shift 3 back
+			{ 2, 6, 3,      0, 1, 5, 6, 7, 8, 2, 3, 4, 9 },
+			// Shift 3 to back
+			{ 2, 7, 3,      0, 1, 5, 6, 7, 8, 9, 2, 3, 4 },
+			// Shift from 3 front
+			{ 0, 5, 3,      3, 4, 5, 6, 7, 0, 1, 2, 8, 9 },
+
+			// Moving many to an earlier point in the array
+			// Shift 3 forward
+			{ 6, 2, 3,      0, 1, 6, 7, 8, 2, 3, 4, 5, 9 },
+			// Shift 3 to front
+			{ 6, 0, 3,      6, 7, 8, 0, 1, 2, 3, 4, 5, 9 },
+			// Shift from 3 back
+			{ 7, 3, 3,      0, 1, 2, 7, 8, 9, 3, 4, 5, 6 }
+		};
+
+		for (Integer[] entry : data) {
+			Integer[] ints = getIntsList();
+			ArrayUtil.arrayMoveWithin(ints, entry[0], entry[1], entry[2]);
+			assertArrayEquals(ints, Arrays.copyOfRange(entry, 3, 13));
+		}
+
+		// Check can't shift more than we have
+		assertThrows(IllegalArgumentException.class, () -> ArrayUtil.arrayMoveWithin(getIntsList(), 7, 3, 5));
+		// Good, we don't have 5 from 7 onwards
+
+		// Check can't shift where would overshoot
+		assertThrows(IllegalArgumentException.class, () -> ArrayUtil.arrayMoveWithin(getIntsList(), 2, 7, 5));
+		// Good, we can't fit 5 in starting at 7
+	}
+}