changes added

src/main/java/com/github/curriculeon/Classroom.java

@@ -0,0 +1,29 @@
+package com.github.curriculeon;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public enum Classroom {
+    INSTANCE;
+    private Students students = Students.getInstance();
+    private Instructors instructors = Instructors.getInstance();
+
+    public void hostLecture(Teacher teacher, Double numberOfHours) {
+        teacher.lecture((Learner[])students.toArray(), numberOfHours);
+    }
+
+    public void hostLecture(long id, double numberOfHours) {
+        Teacher instructor = instructors.findById(id);
+        instructor.lecture(students.toArray(), numberOfHours);
+    }
+
+    public Map<Student, Double> getStudyMap() {
+        Map<Student,Double> result = new HashMap<>();
+        for (Person studentAsPerson : students.toArray()) {
+            Student student = (Student)studentAsPerson;
+            Double studyTime = student.getTotalStudyTime();
+            result.put(student, studyTime);
+        }
+        return result;
+    }
+}

src/main/java/com/github/curriculeon/Instructor.java

@@ -0,0 +1,22 @@
+package com.github.curriculeon;
+
+public class Instructor extends Person implements Teacher {
+
+    public Instructor(long id, String name) {
+        super(id,name);
+    }
+
+    @Override
+    public void teach(Learner learner, double numberOfHours) {
+        learner.learn(numberOfHours);
+    }
+
+    @Override
+    public void lecture(Learner[] learners, double numberOfHours) {
+        double numberOfHoursPerLearner = numberOfHours / learners.length;
+        for (int i =0; i < learners.length ; i++) {
+            Learner learner = learners[i];
+            learner.learn(numberOfHoursPerLearner);
+        }
+    }
+}

src/main/java/com/github/curriculeon/Instructors.java

@@ -0,0 +1,25 @@
+package com.github.curriculeon;
+
+import java.util.List;
+
+public class Instructors extends People<Instructor> {
+
+    private static final Instructors instance = new Instructors();
+
+    private Instructors() {
+        this.add(new Instructor(0L, "Leon Hunter"));
+        this.add(new Instructor(1L, "someone"));
+    }
+
+    @Override
+    public Person[] toArray() {
+        int sizeOfArray = count();
+        Instructor[] destinationArray = new Instructor[sizeOfArray];
+        List<Instructor> sourceList = personList;
+        return sourceList.toArray(destinationArray);
+    }
+
+    public static Instructors getInstance() {
+        return instance;
+    }
+}

src/main/java/com/github/curriculeon/Learner.java

@@ -0,0 +1,6 @@
+package com.github.curriculeon;
+
+public interface Learner {
+    void learn(double numberOfHours);
+    double getTotalStudyTime();
+}

src/main/java/com/github/curriculeon/People.java

@@ -0,0 +1,60 @@
+package com.github.curriculeon;
+
+import java.lang.reflect.Array;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+abstract public class People<SomeLearnerType extends Person> implements Iterable<SomeLearnerType>{
+
+    List<SomeLearnerType> personList;
+
+    public People() {
+        this(new ArrayList<>());
+    }
+
+    public People(List<SomeLearnerType> personList) {
+        this.personList = personList;
+    }
+
+    public void add(SomeLearnerType personToBeAdded) {
+        this.personList.add(personToBeAdded);
+    }
+
+    public SomeLearnerType findById(long id) {
+        for (int i = 0; i < personList.size(); i++) {
+            SomeLearnerType person = personList.get(i);
+            if (person.getId() == id) { //if the id is correct,
+                return person; // return person
+            } else { // if its the wrong id,
+                continue; // keep lookin'!
+            }
+        } // finished loop; we've finished lookin'
+        return null; // we were not able to find the person with the id
+    }
+
+    public Boolean contains(SomeLearnerType  personToBeFound) {
+      return personList.contains(personToBeFound);
+    }
+
+    public void remove(SomeLearnerType  person) {
+        personList.remove(person);
+    }
+
+    public void removeAll() {
+        personList.clear();
+    }
+
+    public int count() {
+        return personList.size();
+    }
+
+    public Person[] toArray() {
+      return personList.toArray(new Person[personList.size()]);
+    }
+
+    @Override
+    public Iterator<SomeLearnerType > iterator() {
+        return personList.iterator();
+    }
+}

src/main/java/com/github/curriculeon/Person.java

@@ -1,5 +1,28 @@
 package com.github.curriculeon;
 
 public class Person {
+    private final long id;
+    private String name;
 
+    public Person() {
+        this.id = -1;
+        this.name = null;
+    }
+
+    public Person(long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public long getId() {
+        return this.id;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
 }

src/main/java/com/github/curriculeon/Student.java

@@ -0,0 +1,19 @@
+package com.github.curriculeon;
+
+public class Student extends Person implements Learner {
+    private double totalStudyTime;
+
+    public Student(long id, String name) {
+        super(0,"some Name");
+    }
+
+    @Override
+    public void learn(double numberOfHours) {
+        this.totalStudyTime += numberOfHours;
+    }
+
+    @Override
+    public double getTotalStudyTime() {
+        return this.totalStudyTime;
+    }
+}

src/main/java/com/github/curriculeon/Students.java

@@ -0,0 +1,27 @@
+package com.github.curriculeon;
+
+import java.util.List;
+
+public class Students extends People<Student> {
+
+    private static final Students INSTANCE = new Students();
+
+    private Students() {
+        super(); // optional invocation
+        this.add(new Student(0L,"OneMore"));
+        this.add(new Student(1L,"someone"));
+        this.add(new Student(2L,"AnotherOne"));
+    }
+
+    @Override
+    public Student[] toArray() {
+        int sizeOfArray = count();
+        Student[] destinationArray = new Student[sizeOfArray];
+        List<Student> sourceList = personList;
+        return sourceList.toArray(destinationArray);
+    }
+
+    public static Students getInstance() {
+        return INSTANCE;
+    }
+}

src/main/java/com/github/curriculeon/Teacher.java

@@ -0,0 +1,8 @@
+package com.github.curriculeon;
+
+import com.github.curriculeon.Learner;
+
+public interface Teacher {
+    void teach(Learner learner, double numberOfHours );
+    void lecture(Learner[] learners, double numberOfHours);
+}

src/test/java/com/github/curriculeon/TestClassroom.java

@@ -0,0 +1,22 @@
+package com.github.curriculeon;
+
+import org.junit.Test;
+
+import java.util.Map;
+
+public class TestClassroom {
+
+    @Test
+    public void testHoursLecture() {
+        Classroom classroom = Classroom.INSTANCE;
+        Teacher lecturer = (Teacher) Instructors.getInstance().findById(1L);
+        Integer numberOfStudents = Students.getInstance().count();
+        Map<Student, Double> preStudyTimeMap = classroom.getStudyMap();
+        Double numberOfHoursToLecture = 300.0;
+        Double numberOfHoursStudidedPerStudent = numberOfHoursToLecture / numberOfStudents;
+
+        // when
+        classroom.hostLecture(lecturer, numberOfHoursToLecture);
+        Map<Student, Double> newStudyMap = classroom.getStudyMap();
+    }
+}

src/test/java/com/github/curriculeon/TestInstructor.java

@@ -0,0 +1,68 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestInstructor {
+
+    @Test
+    public void testImplementation() {
+
+        //given
+        Instructor instructor = new Instructor(-1,null);
+
+        //when
+        Boolean outcome = instructor instanceof Teacher;
+
+        //then
+        Assert.assertTrue(outcome);
+    }
+
+    @Test
+    public void testInheritance() {
+        Instructor instructor = new Instructor(-1, null);
+        Boolean outcome = instructor instanceof Person;
+        Assert.assertTrue(outcome);
+    }
+
+    @Test
+    public void testTeach() {
+        // given
+        Instructor instructor = new Instructor(-1, null);
+        Learner learner = new Student(-1, null);
+        Double numberOfHoursToTeach = 134.0;
+        Double preStudyTime = learner.getTotalStudyTime();
+        Double expected = preStudyTime + numberOfHoursToTeach;
+
+        // when
+        instructor.teach(learner,numberOfHoursToTeach);
+        Double actual = learner.getTotalStudyTime();
+
+        // then
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testLecture() {
+        //given
+        Teacher teacher = new Instructor(-1, null);
+        Learner[] learners = new Learner[] {
+                new Student(0L, "Leon"),
+                new Student(1L, "Christopher"),
+                new Student(2L, "Hunter")
+        };
+        Double numberOfHours = 128.0;
+        Double expected = numberOfHours / learners.length;
+
+        // when
+        teacher.lecture(learners,numberOfHours);
+
+        //then
+        for (int i =0 ; i < learners.length ; i++) {
+            Learner learner = learners[i];
+            Double actual = learner.getTotalStudyTime();
+            Assert.assertEquals(expected,actual);
+        }
+
+    }
+}

src/test/java/com/github/curriculeon/TestInstructors.java

@@ -0,0 +1,18 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class TestInstructors {
+    @Test
+    public void test() {
+        Instructors instructors = Instructors.getInstance();
+        List<String> expectedNames = Arrays.asList("Leon Hunter", "someone");
+        for(Person instructor : instructors.toArray()) {
+            Assert.assertTrue(expectedNames.contains(instructor));
+        }
+    }
+}