completed up until 5.1

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

@@ -0,0 +1,32 @@
+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(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(Student student : students.toArray()) {
+            Double studyTime = student.getTotalStudyTime();
+            result.put(student, studyTime);
+        }
+        return result;
+    }
+
+}
+
+
+

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

@@ -0,0 +1,30 @@
+package com.github.curriculeon;
+
+public enum Educator implements Teacher {
+    PROFESSORPEEP;
+
+    private Double hoursWorked;
+    private final Instructor instructor;
+
+    Educator() {
+        long id = this.ordinal(); // inherited from `Enum` implicit super class
+        String name = this.name();  // inherited from `Enum` implicit super class
+        this.instructor = new Instructor(id, name);
+        Instructors.getInstance().add(instructor);
+    }
+
+
+    @Override
+    public void teach(Learner learner, double numberOfHours) {
+        instructor.teach(learner, numberOfHours);
+        hoursWorked += numberOfHours;
+
+    }
+
+    @Override
+    public void lecture(Learner[] learners, double numberOfHours) {
+        instructor.lecture(learners, numberOfHours);
+        hoursWorked += numberOfHours;
+
+    }
+}

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

@@ -0,0 +1,24 @@
+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 +1,28 @@
+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, "Professor Peep"));
+        this.add(new Instructor(0L, "Professor George"));
+    }
+
+    @Override
+    public Instructor[] 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 +1,7 @@
+package com.github.curriculeon;
+
+public interface Learner {
+    void learn(Double numberOfHours);
+
+    Double getTotalStudyTime();
+}

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

@@ -0,0 +1,71 @@
+package com.github.curriculeon;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * Created by leon on 7/22/2020.
+ */
+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 person) {
+        this.personList.add(person);
+    }
+
+    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 SomeLearnerType findByIdExpanded(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 specifiedPerson) {
+        return personList.contains(specifiedPerson);
+    }
+
+    public void remove(SomeLearnerType someSpecificPerson) {
+        personList.remove(someSpecificPerson);
+    }
+
+    public void removeAll() {
+        personList.clear();
+    }
+
+    public int count() {
+        return personList.size();
+    }
+
+    abstract public SomeLearnerType[] toArray();
+
+    @Override
+    public Iterator<SomeLearnerType> iterator() {
+        return personList.iterator();
+    }
+}

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

@@ -1,5 +1,29 @@
+
 package com.github.curriculeon;
 
 public class Person {
+    private final Long id;
+    private String name;
+
+    public Person() {
+        this.id = null;
+    }
+
+    public Person(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+
+    public Long getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
 
-}
+    public void setName(String name) {
+        this.name = name;
+    }
+}

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

@@ -0,0 +1,20 @@
+package com.github.curriculeon;
+
+public class Student extends Person implements Learner {
+
+    private double totalStudyTime;
+
+    public Student(Long id, String name) {
+        super(id, name);
+    }
+
+    @Override
+    public void learn(Double numberOfHours) {
+        this.totalStudyTime =  totalStudyTime + numberOfHours;
+    }
+
+    @Override
+    public Double getTotalStudyTime() {
+        return totalStudyTime;
+    }
+}

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

@@ -0,0 +1,28 @@
+package com.github.curriculeon;
+import java.util.List;
+
+public class Students extends People<Student> {
+
+
+    private static final Students INSTANCE = new Students();
+
+    private Students() {
+        super();
+        this.add(new Student(0L, "Steven"));
+        this.add(new Student(1L, "Greg"));
+        this.add(new Student(2L, "Joe"));
+
+    }
+
+    @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 +1,7 @@
+package com.github.curriculeon;
+
+public interface Teacher {
+
+    void teach(Learner learner, double numberOfHours);
+    void lecture(Learner[] learner, double numberOfHours);
+}

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

@@ -0,0 +1,37 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Created by leon on 7/27/2020.
+ */
+public class TestClassroom {
+    @Test
+    public void testHostLecture() {
+        // given
+        Classroom classroom = Classroom.INSTANCE;
+        Teacher teacher = Instructors.getInstance().findById(0L);
+        Integer numberOfStudents = Students.getInstance().count();
+        Double numberOfHoursToLecture = numberOfStudents.doubleValue();
+        Double expectedNumberOfHoursLearned = numberOfHoursToLecture / numberOfStudents;
+        Map<Student, Double> preStudyMap = classroom.getStudyMap();
+
+        // when
+        classroom.hostLecture(teacher, numberOfHoursToLecture);
+        Map<Student, Double> postStudyMap = classroom.getStudyMap();
+        Set<Student> keySet = postStudyMap.keySet();
+        for (Student student : keySet) {
+            Double preStudyTime = preStudyMap.get(student);
+            Double expectedStudyTime = preStudyTime + expectedNumberOfHoursLearned;
+            Double actualStudyTime = postStudyMap.get(student);
+
+            // then
+            Assert.assertEquals(expectedStudyTime, actualStudyTime);
+        }
+
+    }
+}

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

@@ -0,0 +1,69 @@
+package com.github.curriculeon;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestInstructor {
+    @Test
+    public void testImplementation() {
+        // given
+        Instructor instructor = new Instructor(null, null);
+
+        // when
+        Boolean result = instructor instanceof Teacher;
+
+        // then
+        Assert.assertTrue(result);
+    }
+    @Test
+    public void testInheritance() {
+        // given
+        Instructor instructor = new Instructor(null, null);
+
+        // when
+        boolean outcome = instructor instanceof Person;
+
+        // then
+        Assert.assertTrue(outcome);
+    }
+
+    @Test
+    public void testTeach() {
+        // given
+        Instructor instructor = new Instructor(null, null);
+        Learner learner = new Student(null, 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(null, 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);
+        }
+    }
+}