diff --git a/core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/modulo/ModuloUnitTest.java b/core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/modulo/ModuloUnitTest.java
index 8b3685adf3..0a9418cb17 100644
--- a/core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/modulo/ModuloUnitTest.java
+++ b/core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/modulo/ModuloUnitTest.java
@@ -1,54 +1,77 @@
 package com.baeldung.modulo;
 
+import static org.junit.Assert.assertEquals;
+
 import org.junit.Test;
 import static org.assertj.core.api.Java6Assertions.*;
 
 public class ModuloUnitTest {
 
-  @Test
-  public void whenIntegerDivision_thenLosesRemainder(){
-    assertThat(11 / 4).isEqualTo(2);
-  }
-
-  @Test
-  public void whenDoubleDivision_thenKeepsRemainder(){
-    assertThat(11 / 4.0).isEqualTo(2.75);
-  }
-
-  @Test
-  public void whenModulo_thenReturnsRemainder(){
-    assertThat(11 % 4).isEqualTo(3);
-  }
-
-  @Test(expected = ArithmeticException.class)
-  public void whenDivisionByZero_thenArithmeticException(){
-    double result = 1 / 0;
-  }
-
-  @Test(expected = ArithmeticException.class)
-  public void whenModuloByZero_thenArithmeticException(){
-    double result = 1 % 0;
-  }
-
-  @Test
-  public void whenDivisorIsOddAndModulusIs2_thenResultIs1(){
-    assertThat(3 % 2).isEqualTo(1);
-  }
-
-  @Test
-  public void whenDivisorIsEvenAndModulusIs2_thenResultIs0(){
-    assertThat(4 % 2).isEqualTo(0);
-  }
-
-  @Test
-  public void whenItemsIsAddedToCircularQueue_thenNoArrayIndexOutOfBounds(){
-    int QUEUE_CAPACITY= 10;
-    int[] circularQueue = new int[QUEUE_CAPACITY];
-    int itemsInserted = 0;
-    for (int value = 0; value < 1000; value++) {
-      int writeIndex = ++itemsInserted % QUEUE_CAPACITY;
-      circularQueue[writeIndex] = value;
+    @Test
+    public void whenIntegerDivision_thenLosesRemainder() {
+        assertThat(11 / 4).isEqualTo(2);
+    }
+
+    @Test
+    public void whenDoubleDivision_thenKeepsRemainder() {
+        assertThat(11 / 4.0).isEqualTo(2.75);
+    }
+
+    @Test
+    public void whenModulo_thenReturnsRemainder() {
+        assertThat(11 % 4).isEqualTo(3);
+    }
+
+    @Test(expected = ArithmeticException.class)
+    public void whenDivisionByZero_thenArithmeticException() {
+        double result = 1 / 0;
+    }
+
+    @Test(expected = ArithmeticException.class)
+    public void whenModuloByZero_thenArithmeticException() {
+        double result = 1 % 0;
+    }
+
+    @Test
+    public void whenDivisorIsOddAndModulusIs2_thenResultIs1() {
+        assertThat(3 % 2).isEqualTo(1);
+    }
+
+    @Test
+    public void whenDivisorIsEvenAndModulusIs2_thenResultIs0() {
+        assertThat(4 % 2).isEqualTo(0);
+    }
+
+    @Test
+    public void whenDividendIsNegativeAndModulusIs2_thenResultIsNegative() {
+        assertEquals(-1, -9 % 2);
+    }
+
+    @Test
+    public void whenDividendIsNegativeAndRemainderIsCheckedForNegativeValue_thenResultIsPositive() {
+        int remainder = -9 % 2;
+
+        if (remainder < 0) {
+            remainder += 2;
+        }
+        assertEquals(1, remainder);
+    }
+
+    @Test
+    public void whenDividendIsNegativeAndUsesMathClass_thenResultIsPositive() {
+        int remainder = Math.floorMod(-9, 2);
+        assertEquals(1, remainder);
+    }
+
+    @Test
+    public void whenItemsIsAddedToCircularQueue_thenNoArrayIndexOutOfBounds() {
+        int QUEUE_CAPACITY = 10;
+        int[] circularQueue = new int[QUEUE_CAPACITY];
+        int itemsInserted = 0;
+        for (int value = 0; value < 1000; value++) {
+            int writeIndex = ++itemsInserted % QUEUE_CAPACITY;
+            circularQueue[writeIndex] = value;
+        }
     }
-  }
 
 }