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接下来是我认为是我的练习java文件的成品。我运行了TestStudent.java文件，并收到了除了s1对象之外的所有正确输出。我已经尝试了“this”操作符和“get”方法，用于showStudentInformation（）方法中的name，studentNumber和course，但仍然没有成功。

/*
    Given the partial code for the class Student that contains 3 attributes: name, studentNumber and course.
    You are to provide the setter and getter methods as well as the body of the constructor that has a missing body.
    You are also required to provide an implementation to the method showStudentInformation() so that once it is 
    called it should display the name, studentNumber and course of the Student object.
*/   

public class Student
{
    private String name;
    private int studentNumber;
    private String course;

    // this is constructor #1 - no need to add anything here
    public Student()
    {}

    // this is constructor #2 - you have to provide the body of this constructor
    public Student(String name, int studentNumber, String course)
    {
        name = this.name;
        studentNumber = this.studentNumber;
        course = this.course;
    }

    // put your setters here
    public void setName(String n) {
        this.name = n;
    }

    public void setStudentNum(Integer s) {
        this.studentNumber = s;
    }

    public void setCourse(String c) {
        this.course = c;
    }

    // put your getters here
    public String getName() {
        return this.name;
    }

    public String getCourse() {
        return this.course;
    }

    public Integer getStudentNo() {
        return this.studentNumber;
    }

    public String showStudentInformation()
    {
        return name + " " + studentNumber + " " + course; 
        // this method should display the name, studentNumber and the course of the student object.
    }
}

public class TestStudent
{
    public static void main(String args[])
    {
        Student s1 = new Student("James", 1111, "Computer Science");
        Student s2 = new Student();
        Student s3 = new Student();

        // set the properties of Student s2, assign a name, studentNumber and course
                s2.setName("Koda");
                s2.setStudentNum(2222);
                s2.setCourse("Business");
        // set the properties of Student s3, assign a name, studentNumber and course
                s3.setName("Bob");
                s3.setStudentNum(3333);
                s3.setCourse("IT");

        // print the identity of Student s1
                s1.showStudentInformation();

        // print the identity of Student s2 by calling the getter methods
                System.out.println(s2.getName() + s2.getStudentNo() + s2.getCourse());
        // print the identity of Student s3 by calling the showStudentInformation() method
                s3.showStudentInformation();
    }   

}

我使用的是在线编译器，目录中的文件是/home/Student.java和/home/TestStudent.java
注意有2个java文件