SchoolTest.java

import org.junit.Before;
import org.junit.Ignore;
import org.junit.Test;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.List;
import java.util.Collection;

import org.hamcrest.Matcher;
import org.hamcrest.collection.IsIterableContainingInOrder;
import static org.hamcrest.CoreMatchers.*;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.assertEquals;

public class SchoolTest {
  private School school;

  @Before
  public void setUp() {
    school = new School();
  }

  @Test
  public void startsWithNoStudents() {
    assertThat(school.numberOfStudents(), is(0));
  }

  @Ignore("Remove to run test")
  @Test
  public void addsStudents() {
    school.add("Aimee", 2);
    assertThat(school.grade(2), hasItem("Aimee"));
  }

  @Ignore("Remove to run test")
  @Test
  public void addsMoreStudentsInSameGrade() {
    final int grade = 2;
    school.add("James", grade);
    school.add("Blair", grade);
    school.add("Paul", grade);

    assertThat(school.grade(grade).size(), is(3));
    assertThat(school.grade(grade), allOf(hasItem("James"), hasItem("Blair"), hasItem("Paul")));
  }

  @Ignore("Remove to run test")
  @Test
  public void addsStudentsInMultipleGrades() {
    school.add("Chelsea", 3);
    school.add("Logan", 7);

    assertThat(school.numberOfStudents(), is(2));
    assertThat(school.grade(3).size(), is(1));
    assertThat(school.grade(3), hasItem("Chelsea"));
    assertThat(school.grade(7).size(), is(1));
    assertThat(school.grade(7), hasItem("Logan"));
  }

  @Ignore("Remove to run test")
  @Test
  public void getsStudentsInEmptyGrade() {
    assertTrue(school.grade(1).isEmpty());
  }

  @Ignore("Remove to run test")
  @Test
  public void sortsSchool() {
    school.add("Kyle", 4);
    school.add("Zed", 4);
    school.add("Adam", 4);
    school.add("Jennifer", 4);
    school.add("Kareem", 6);
    school.add("Christopher", 4);
    school.add("Kylie", 3);
    Map<Integer, Matcher> sortedStudents = new HashMap<Integer, Matcher>();
    sortedStudents.put(6, IsIterableContainingInOrder
      .contains("Kareem"));
    sortedStudents.put(4, IsIterableContainingInOrder
      .contains("Adam", "Christopher", "Jennifer", "Kyle", "Zed"));
    sortedStudents.put(3, IsIterableContainingInOrder
      .contains("Kylie"));

    Map schoolStudents = school.studentsByGradeAlphabetical();
    for (Map.Entry<?, Matcher> entry : sortedStudents.entrySet()) {

      assertThat((Collection) schoolStudents.get(entry.getKey()), entry.getValue());
    }
  }

  @Ignore("Remove to run test")
  @Test
  public void modifyingFetchedGradeShouldNotModifyInternalDatabase() {
    String shouldNotBeAdded = "Should not be added to school";
    int grade = 1;

    Collection students = school.grade(grade);

    try {
      students.add(shouldNotBeAdded);
    } catch (Exception exception) {
      // Also valid that the add operation throws an exception
      // Such as UnsupportedOperationException when an umodifiable collection type is used
    }

    assertThat(school.grade(grade), not(hasItem(shouldNotBeAdded)));
  }

  @Ignore("Remove to run test")
  @Test
  public void modifyingSortedStudentsShouldNotModifyInternalDatabase() {
    int grade = 2;
    String studentWhichShouldNotBeAdded = "Should not be added";
    List<String> listWhichShouldNotBeAdded = new ArrayList<>();
    listWhichShouldNotBeAdded.add(studentWhichShouldNotBeAdded);

    Map sortedStudents = school.studentsByGradeAlphabetical();

    try {
      sortedStudents.put(grade, listWhichShouldNotBeAdded);
    } catch (Exception exception) {
      // Also valid that the put operation throws an exception
      // Such as UnsupportedOperationException when an unmodifiableMap is used
    }

    assertThat(school.studentsByGradeAlphabetical().get(grade),
      not(hasItem(studentWhichShouldNotBeAdded)));
  }
}