Merge pull request #5467 from eugenp/bael-2123-modulo

Bael 2123 modulo

core-java-8/findItemsBasedOnValues/.gitignore

@@ -1 +0,0 @@
-/bin/

core-java-collections/src/test/java/com/baeldung/findItems/FindItemsBasedOnOtherStreamUnitTest.java

@@ -1,4 +1,4 @@
-package findItems;
+package com.baeldung.findItems;
 
 import static org.junit.Assert.assertEquals;
 
@@ -10,24 +10,20 @@ import java.util.stream.Collectors;
 
 import org.junit.Test;
 
-public class FindItemsBasedOnValues {
+public class FindItemsBasedOnOtherStreamUnitTest {
 
-    List<Employee> EmplList = new ArrayList<Employee>();
+    private List<Employee> employeeList = new ArrayList<Employee>();
-    List<Department> deptList = new ArrayList<Department>();
 
-    public static void main(String[] args) throws ParseException {
+    private List<Department> departmentList = new ArrayList<Department>();
-        FindItemsBasedOnValues findItems = new FindItemsBasedOnValues();
-        findItems.givenDepartmentList_thenEmployeeListIsFilteredCorrectly();
-    }
 
     @Test
     public void givenDepartmentList_thenEmployeeListIsFilteredCorrectly() {
         Integer expectedId = 1002;
 
-        populate(EmplList, deptList);
+        populate(employeeList, departmentList);
 
-        List<Employee> filteredList = EmplList.stream()
+        List<Employee> filteredList = employeeList.stream()
-            .filter(empl -> deptList.stream()
+            .filter(empl -> departmentList.stream()
                 .anyMatch(dept -> dept.getDepartment()
                     .equals("sales") && empl.getEmployeeId()
                     .equals(dept.getEmployeeId())))
@@ -53,16 +49,16 @@ public class FindItemsBasedOnValues {
 }
 
 class Employee {
-    Integer employeeId;
+    private Integer employeeId;
-    String employeeName;
+    private String employeeName;
 
-    public Employee(Integer employeeId, String employeeName) {
+    Employee(Integer employeeId, String employeeName) {
         super();
         this.employeeId = employeeId;
         this.employeeName = employeeName;
     }
 
-    public Integer getEmployeeId() {
+    Integer getEmployeeId() {
         return employeeId;
     }
 
@@ -73,20 +69,20 @@ class Employee {
 }
 
 class Department {
-    Integer employeeId;
+    private Integer employeeId;
-    String department;
+    private String department;
 
-    public Department(Integer employeeId, String department) {
+    Department(Integer employeeId, String department) {
         super();
         this.employeeId = employeeId;
         this.department = department;
     }
 
-    public Integer getEmployeeId() {
+    Integer getEmployeeId() {
         return employeeId;
     }
 
-    public String getDepartment() {
+    String getDepartment() {
         return department;
     }
 

core-java/src/test/java/com/baeldung/modulo/ModuloUnitTest.java

@@ -0,0 +1,54 @@
+package com.baeldung.modulo;
+
+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;
+    }
+  }
+
+}