init

lab/lab3/Question5/Student.java

@@ -0,0 +1,166 @@
+/*
+ * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
+ * Date: 2022/03/03
+ * Description: Student class
+ */
+
+public class Student {
+    /**
+     * Student's ID number
+     */
+    private int ID;
+
+    /**
+     * Student's name
+     */
+    private String name;
+
+    /**
+     * A single character representing the grade of the student
+     */
+    private char grade;
+
+    /**
+     * Constructor A public constructor with one parameter
+     * 
+     * @param id   the ID of the student, only accept positive integer if the id is
+     *             not positive, it will be set to 0
+     * 
+     * @param name the name of the student.
+     */
+    public Student(int ID, String name) {
+        this(ID, name, 'A');
+    }
+
+    /**
+     * Constructor A public constructor with three parameters
+     * 
+     * @param id    the ID of the student, only accept positive integer if the id is
+     *              not positive, it will be set to 0
+     * 
+     * @param name  the name of the student.
+     * 
+     * @param grade the grade of the student, if the grade is not one of these, it
+     *              will be set to 'A'
+     */
+    public Student(int ID, String name, char grade) {
+        // if the id is not positive, set it to 0
+        if (ID > 0) {
+            this.ID = ID;
+        } else {
+            this.ID = 0;
+        }
+
+        // set the name
+        this.name = name;
+
+        // set the grade
+        this.grade = grade;
+    }
+
+    /**
+     * Getter A public getter for the ID.
+     * 
+     * @return the ID of the student
+     */
+    public int getID() {
+        return ID;
+    }
+
+    /**
+     * Getter A public getter for the name.
+     * 
+     * @return the name of the student
+     */
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Setter A public setter for the name.
+     *
+     * @param name the name of the student
+     * 
+     * @return void
+     */
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    /**
+     * Getter A public getter for the grade.
+     * 
+     * @return the grade of the student
+     */
+    public char getGrade() {
+        return grade;
+    }
+
+    /**
+     * Setter A public setter for the grade.
+     *
+     * @param grade the grade of the student
+     *
+     * @return void
+     */
+    public void setGrade(char grade) {
+        this.grade = grade;
+    }
+
+    /**
+     * Test method A public method to test the class
+     *
+     * @return void
+     */
+    public static void testStudent() {
+        // create students
+        Student s1 = new Student(-1, "Walter");
+        Student s2 = new Student(0, "Yongyuan");
+        Student s3 = new Student(1, "Chen");
+
+        // print true for id
+        System.out.println(s1.getID() == 0);
+        System.out.println(s2.getID() == 0);
+        System.out.println(s3.getID() == 1);
+
+        // print true for name
+        System.out.println(s1.getName().equals("Walter"));
+        System.out.println(s2.getName().equals("Yongyuan"));
+        System.out.println(s3.getName().equals("Chen"));
+
+        // change the name
+        s1.setName("Walter Wang");
+        s2.setName("Yongyuan Wang");
+        s3.setName("Chen Wang");
+
+        // print true for name
+        System.out.println(s1.getName().equals("Walter Wang"));
+        System.out.println(s2.getName().equals("Yongyuan Wang"));
+        System.out.println(s3.getName().equals("Chen Wang"));
+
+        // check default grade
+        System.out.println(s1.getGrade() == 'A');
+        System.out.println(s2.getGrade() == 'A');
+        System.out.println(s3.getGrade() == 'A');
+
+        // set grade
+        s1.setGrade('B');
+        s2.setGrade('C');
+        s3.setGrade('D');
+
+        // check grade
+        System.out.println(s1.getGrade() == 'B');
+        System.out.println(s2.getGrade() == 'C');
+        System.out.println(s3.getGrade() == 'D');
+
+        // create students with grade different from A
+        Student s4 = new Student(2, "Chen", 'B');
+        Student s5 = new Student(3, "Yongyuan", 'C');
+        Student s6 = new Student(4, "Walter", 'D');
+
+        // print true for grade
+        System.out.println(s4.getGrade() == 'B');
+        System.out.println(s5.getGrade() == 'C');
+        System.out.println(s6.getGrade() == 'D');
+    }
+}