构造函数Teacher（Teacher）未定义

Question

我在名为'Department'的类中使用了复制构造函数和继承来调用来自'Teacher'类的信息，该类是'Person'的子类。创建set / get方法后，我得到了上面的错误。任何人都知道为什么会发生这种情况？

“部门”类的代码：

public class Department {
private String deptName;
private int numMajors;
private Teacher[] listTeachers; //inherits from Person class
private Student[] listStudents; //inherits from Person class

    // First constructor for Department
    public Department(String dn, int nm, Teacher[] listTeachers, Student[] listStudents) {
    this.deptName = dn;
    this.numMajors = nm;

    this.listTeachers = new Teacher[listTeachers.length];
    for (int i = 0; i < this.listTeachers.length; i++)
    {
        this.listTeachers[i] = new Teacher (listTeachers[i]);
    }

    //set method for Teachers Array
    public void setListTeachers (Teacher[] other) {
    this.listTeachers = new Teacher[other.length];
    for (int i = 0; i < listTeachers.length; i++) {
        this.listTeachers[i] = new Teacher (other[i]);
    }
}

    //get method for Teachers Array
    public Teacher[] getListTeachers() {
    Teacher[] copyTeachers = new Teacher[listTeachers.length];
    for (int i = 0; i < copyTeachers.length; i++) {
        copyTeachers[i] = new Teacher(this.listTeachers[i]);
    }
    return copyTeachers;
}

以下是给我错误的行：

1）this.listTeachers[i] = new Teacher (listTeachers[i]);

2）this.listTeachers[i] = new Teacher (other[i]);

3）copyTeachers[i] = new Teacher(this.listTeachers[i]);

“教师”课程代码：

public class Teacher extends Person {
private String id;
private int salary;
private int num_yr_prof;

//Constructor for use in Teacher main method.
public Teacher(String n, int a, String s, boolean al, String i, int sal, int numyr) {
    super(n, a, s, al);
    this.id = i;
    this.salary = sal;
    this.num_yr_prof = numyr;
}

//Copy constructor for use in Department class.
public Teacher (String n, int a, String s, boolean al, Teacher other) {
    super(n, a, s, al);
    if (other == null) {
        System.out.println("Fatal Error!");
        System.exit(0);
    }

    this.id = other.id;
    this.salary = other.salary;
    this.num_yr_prof = other.num_yr_prof;
}

Answer 1

您的复制构造函数可能如下所示：

    public Teacher(Teacher teacher) {
        this( teacher.n, teacher.a, teacher.s, teacher.al, 
              teacher.id, teacher.salary, teacher.num_yr_prof );
    }

由于您没有显示Person类的代码，因此我在这里使用了变量名n，a，s和al。它们应该替换为Person类中命名的那些变量。当然，这假设这些变量是公共的或受保护的。如果它们是私有的，则需要对这些变量使用getter（即使它们是公共的或受保护的，也是首选的）。

Answer 2

你需要给你的Teacher类一个接受教师的构造函数：

public Teacher(Teacher teacher) {
// do something
}