|
@@ -129,6 +129,7 @@
|
129
|
129
|
* Create a `ZipCodeWilmington` singleton.
|
130
|
130
|
* The class should declare a field that references the instance of `Students` called `students`.
|
131
|
131
|
* The class should declare a field that references the instance of `Instructors` called `instructors`.
|
|
132
|
+ * The class should define a method `hostLecture` which makes use of a `Teacher teacher, double numberOfHours` parameter to host a `lecture` to the composite `people` field in the `students` reference.
|
132
|
133
|
* The class should define a method `hostLecture` which makes use of a `long id, double numberOfHours` parameter to identify a respective `Instructor` to host a `lecture` to the composite `people` field in the `cohort` reference.
|
133
|
134
|
|
134
|
135
|
-
|
|
@@ -136,8 +137,43 @@
|
136
|
137
|
* Create a `TestZipCodeWilmington` class.
|
137
|
138
|
* Create a `testHostLecture` method which ensures that each of the `Student`'s `totalStudyTime` instance variable is incremented by the specified `numberOfHours` upon invoking the `.hostLecture` method.
|
138
|
139
|
|
|
140
|
+
|
|
141
|
+
|
|
142
|
+
|
|
143
|
+
|
|
144
|
+
|
|
145
|
+
|
|
146
|
+
|
|
147
|
+
|
|
148
|
+-
|
|
149
|
+# Notice the Design Flaw - Odd Casting Issues
|
|
150
|
+* You may have noticed that the `findById`, and `hostLecture` methods require an intermediate [casting trick](https://stackoverflow.com/questions/5289393/casting-variables-in-java).
|
|
151
|
+* To remedy this issue, we can _generify_ the `People` class.
|
|
152
|
+
|
|
153
|
+# Part 9.1 - Modify `People` class
|
|
154
|
+* [Parameterize](https://stackoverflow.com/questions/12551674/what-is-meant-by-parameterized-type) the `People` signature to enfore that it is a container for objects of type `E` such that `E` is a subclass of `Person`.
|
|
155
|
+* Modify `people` field to enforce that is a container of objects of type `E`.
|
|
156
|
+* Modify the `add` method to ensure that it handles object of type `E`.
|
|
157
|
+* Modify the `getArray` method to ensure that it returns an object of type `E[]`.
|
|
158
|
+* Modify the `findById` method to ensure that it returns an object of type `E`.
|
|
159
|
+
|
|
160
|
+# Part 9.2 - Modify `People` subclasses
|
|
161
|
+* Modify the `Students` class signature to ensure that it is a subclass of `People` of parameterized type `Student`.
|
|
162
|
+* Modify the `Instructors` class signature to ensure that it is a subclass of `People` of parameterized type `Instructor`.
|
|
163
|
+
|
|
164
|
+# Part 9.3 - Refactor `ZipCodeWilmington` class
|
|
165
|
+* Refactor the `hostLecture` method in the `ZipCodeWilmington` class by removing any intermediate _casting trick(s)_.
|
|
166
|
+
|
|
167
|
+# Part 9.0 - Test refactored classes.
|
|
168
|
+* Ensure that the `TestStudents`, `TestInstructors`, `TestPeople`, `TestZipCodeWilmington` classes were no affected by the refactor.
|
|
169
|
+
|
|
170
|
+
|
|
171
|
+
|
|
172
|
+
|
|
173
|
+
|
|
174
|
+
|
139
|
175
|
-
|
140
|
|
-# Notice the Design Flaw
|
|
176
|
+# Notice the Design Flaw - Non-Intuitive Orientation
|
141
|
177
|
* You may have notice that `findById` makes it difficult to intuitively identify _which_ `Person` object is being returned.<br>
|
142
|
178
|
Additionally, it's challengaing to ensure **every** `Person` instance has a unique ID amongst its respective `People` subclass.<br>
|
143
|
179
|
To remedy this issue, we redesign and refactor.
|