"안녕, 아미고!"
"안녕하세요, 다람쥐 선장입니다!"
"냄새가 나니, 병사?"
"아니요."
"냄새는 아마도 단말기에서 나는 것 같습니다. 거기서 무엇을 하고 있는지 봅시다."
"응? 어떻게 코드가 냄새가 날 수 있지?"
"맞아, 확실히 냄새가 나지는 않지만... 하지만 종종 냄새가 난다."
"선장님, 저는 선박을 위한 새로운 인사 관리 시스템을 개발하고 있습니다. 보세요, 프로젝트가 거의 준비되었습니다."
"음, 이제 리팩토링에서 Zen을 달성할 때입니다. 그래야만 코드를 정리할 수 있습니다. IntelliJ IDEA 요원에게 과제를 문의하세요. 그가 모든 지침을 알려줄 것입니다."
"예, 선생님! 주문을 수행합니다."
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 1)
It's time for a little refactoring. Wikipedia says, "Refactoring
or reorganizing code is the process of changing the internal structure of a program, without
affecting its external behavior and with an aim to making it easier to understand.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 2)
2.1. Extract a subclass.
2.1.1. Add the Soldier class to the human package.
2.1.2. Get rid of the isSoldier field.
2.1.3. Move the necessary methods from Human to Soldier.
2.1.4. Update the Human constructor's signature.
2.2. Pull up the body of the constructor.
7
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 3)
3.1. Push down a field. Push down the course field to the appropriate class. Make it private.
3.2. Push down a method. Push down the getter for the course field to the appropriate class.
3.3. Extract an interface.
3.3.1. Create an Alive interface in the human package.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 4)
4.1. Replace inheritance with delegation.
4.1.1. The University class must not inherit Student.
4.1.2. The University class must have a students list. Don't forget to initialize it.
4.1.3. Add a setter and getter for students.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 5)
5.1. Create a template method.
5.1.1. Add a String getPosition() method to the Human class. It should return the string "Person".
5.1.2. Override this method in the Student and Teacher classes. The method should return "Student" and "Teacher", respectively.
28
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 6)
6.1. Replace a parameter with a set of specialized methods. Replace the Student class's setValue() method
with specialized setCourse() and setAverageGrade() methods.
6.2. Add a parameter. Add a double parameter to the getStudentWithAverageGrade() method so the average grade of the required student.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 7)
7.1. Parameterize a method. Replace the incAverageGradeBy01() and incAverageGradeBy02() methods
with an incAverageGrade(double delta) method.
7.2. Pass an entire object. Rewrite the addStudentInfo() method so that it
takes a Student object as an argument.
7
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 8)
8.1. Remove a setter. Remove the setId() method. The id field should be set only when
the object is created.
8.2. Hide a method (field). Change the visibility of the nextId field to match
the area where it is used.
28
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 9)
9.1. Self-encapsulate a field. Rewrite the incAverageGrade() method, using a setter and getter to access averageGrade.
9.2. Replace an array field with an object. Replace the int[] size array with an instance of a new Size type,
containing the following public fields: int height and int weight.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 10)
Understand the code in the car package.
10.1. Replace a constructor with a factory method.
10.1.1. Declare Truck, Sedan, and Cabriolet classes that inherit Car.
10.1.2. Add constructors that have an int numberOfPassengers constructors.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 11)
11.1. Replace an error code with an exception. Rewrite the fill(double numberOfGallons)
method to throw an Exception if there is an error.
11.2. Decompose a conditional expression.
11.2.1. Add and implement a method in the Car class that determines whether the passed date belongs to
summer.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 12)
12.1. Combine conditional expressions.
12.1.1. In the Car class, add a private method that indicates whether passengers can be carried:
boolean canPassengersBeCarried(). The method should return true if
the driver is available (isDriverAvailable) and there is fuel.
28
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 13)
Understand the code in the user package.
13.1. Extract a method. Add a printInfo() method that displays the first and last name
on the console, formatted as follows -
First name: Jason;
Last name: Slater.
Replace the duplicate code in printUsers() with a method call.
14
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 14)
14.1. Move a field. Replace the isAnnaMale and isRomanMale fields with a male field in the appropriate class.
Add a setter and getter for the new field (when choosing method names, consider the field type).
14.2. Extract a class.
14.2.1. Add an Address class to the user package.
7
과제
Java Multithreading, 레벨 5, 레슨 16
Refactoring (part 15)
Great. You've mastered basic refactoring techniques: Pull up a field, pull up a method, Encapsulate a collection, extract a subclass, pull up the body of a constructor, push down a method, push down a field, extract an interface, collapse a hierarchy, replace inheritance with delegation.