.. _classes-exercises-part2:

Exercises: Objects and Classes, Part 2
=======================================

Work on these exercises in the IntelliJ ``java-web-dev-exercises`` project.
You will update your ``Student.java`` file by implementing the ``addGrade`` and
``getGradeLevel`` methods that were sketched out in the
:ref:`Instance Methods <instance-methods>` section.

The ``getGradeLevel`` Method
-----------------------------

This method returns the student's level based on the number of credits they
have earned: Freshman (0-29 credits), Sophomore (30-59 credits), Junior (60-89
credits), or Senior (90+ credits).

:ref:`Check your solution <classes2-exercise-solutions1>`

The ``addGrade`` Method
------------------------

This method accepts two parameters---a number of course credits and a
numerical grade (0.0-4.0). With this data, you need to update the student’s
GPA.

GPA Information
^^^^^^^^^^^^^^^^

GPA is computed via the formula:

   gpa = (total quality score) / (total number of credits)

#. The *quality score* for a class is found by multiplying the letter grade
   score (0.0-4.0) by the number of credits.
#. The *total quality score* is the sum of the quality scores for all classes.

For example, if a student received an "A" (worth 4 points) in a 3-credit course
and a "B" (worth 3 points) in a 4-credit course, their total quality score
would be: 4.0 * 3 + 3.0 * 4 = 24. Their GPA would then be 24 / 7 = 3.43.

Determine the New GPA
^^^^^^^^^^^^^^^^^^^^^^

To update the student's GPA:

#. Calculate their *current* total quality score by using the formula
   ``gpa * numberOfCredits``.
#. Use the new course grade and course credits to update their total quality
   score.
#. Update the student's total ``numberOfCredits``.
#. Compute their new GPA.

:ref:`Check your solution <classes2-exercise-solutions2>`

``toString`` and ``equals``
----------------------------

#. Add custom ``equals()`` and ``toString()`` methods to the ``Student``
   class.

   :ref:`Check your solution <classes2-exercise-solutions3a>`

#. Add custom ``equals()`` and ``toString()`` methods to the ``Course``
   class which you started in the exercises for the
   :ref:`previous chapter <classes-exercises-part1>`.