String LocalDate birthDate; 需要import嘛
时间: 2024-01-10 07:03:07 浏览: 117
是的,需要导入 LocalDate 所在的包。在 Java 8 中,LocalDate 类位于 java.time 包中,因此需要在代码文件的开头添加以下 import 语句:
```java
import java.time.LocalDate;
```
这样就可以在代码中使用 LocalDate 类了。
相关问题
JAVA Person类(抽象类): 属性:int id, String name, LocalDate birthDate。 方法:构造方法(id, name, year, month, dayOfMonth); id与birthDate的getter方法; name的getter/setter方法; 抽象方法String getPersonInfo(),该方法之所以声明为抽象是因为其在子类返回的信息与子类特有属性相关。 Student类继承自Person类: 属性:int enrollmentYear, String clazzName。 方法:构造方法(id, name, year, month, dayOfMonth, enrollmentYear, clazzName),建议使用super复用Person的构造方法; 覆盖父类的 getPersonInfo()方法,返回"Student-enrollmentYear-name" Teacher类继承自Person: 属性:String department, double salary。 方法:构造方法(id, name, year, month, dayOfMonth, department, salary),建议使用super复用Person的构造方法; 覆盖父类的 getPersonInfo()方法,返回"Teacher-department-name" main方法包含: 输入 : 产生n个对象 如果要生成Student对象则依次输入:姓名 年 月 日 入学年份 班级 如果要生成Teacher对象则依次输入:姓名 年 月 日 系 薪水 输出 : 学生人数,教师人数 n个对象getPersonNumber 输入样例: 6 Liz 1986 10 10 CS 2000 Tom 1978 5 7 CS 2500.5 Sally 2000 1 3 2018 Net01 Jerry 1988 6 7 Mechanical 1990 Eliza 2001 2 5 2019 Software02 Li 1978 5 7 cs 2400 输出样例: Teacher 4人 Student 2人 Teacher-CS-Liz Teacher-CS-Tom Student-2018-Sally Teacher-Mechanical-Jerry Student-2019-Eliza Teacher-cs-Li
好的,您的问题是如何实现这个程序。我将逐步解答您的问题:
首先,我们需要定义一个Person类,包含属性id、name和birthDate,以及一个抽象方法getPersonInfo()。
```java
abstract class Person {
private int id;
private String name;
private LocalDate birthDate;
public Person(int id, String name, int year, int month, int dayOfMonth) {
this.id = id;
this.name = name;
this.birthDate = LocalDate.of(year, month, dayOfMonth);
}
public int getId() {
return id;
}
public LocalDate getBirthDate() {
return birthDate;
}
public String getName() {
return name;
}
public abstract String getPersonInfo();
}
```
然后,我们定义一个Student类,继承Person类,并在其基础上新增enrollmentYear和clazzName属性,并重写getPersonInfo()方法。
```java
class Student extends Person {
private int enrollmentYear;
private String clazzName;
public Student(int id, String name, int year, int month, int dayOfMonth, int enrollmentYear, String clazzName) {
super(id, name, year, month, dayOfMonth);
this.enrollmentYear = enrollmentYear;
this.clazzName = clazzName;
}
public String getClazzName() {
return clazzName;
}
public int getEnrollmentYear() {
return enrollmentYear;
}
@Override
public String getPersonInfo() {
return "Student-" + enrollmentYear + "-" + getName();
}
}
```
最后,我们定义一个Teacher类,同样继承Person类,并新增department和salary属性,并重写getPersonInfo()方法。
```java
class Teacher extends Person {
private String department;
private double salary;
public Teacher(int id, String name, int year, int month, int dayOfMonth, String department, double salary) {
super(id, name, year, month, dayOfMonth);
this.department = department;
this.salary = salary;
}
public double getSalary() {
return salary;
}
public String getDepartment() {
return department;
}
@Override
public String getPersonInfo() {
return "Teacher-" + department + "-" + getName();
}
}
```
现在我们已经定义好了Person、Student和Teacher类,接下来需要在main方法中根据输入信息来产生n个对象,并输出学生和教师的人数以及每个对象的信息。您可以参考以下代码实现:
```java
import java.time.LocalDate;
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
List<Person> people = new ArrayList<>();
int totalStudent = 0;
int totalTeacher = 0;
int n = scanner.nextInt();
for (int i = 0; i < n; i++) {
String name = scanner.next();
int year = scanner.nextInt();
int month = scanner.nextInt();
int dayOfMonth = scanner.nextInt();
if (scanner.hasNextInt()) {
int enrollmentYear = scanner.nextInt();
String clazzName = scanner.next();
Student student = new Student(i + 1, name, year, month, dayOfMonth, enrollmentYear, clazzName);
people.add(student);
totalStudent++;
} else {
String department = scanner.next();
double salary = scanner.nextDouble();
Teacher teacher = new Teacher(i + 1, name, year, month, dayOfMonth, department, salary);
people.add(teacher);
totalTeacher++;
}
}
System.out.printf("Student %d人\nTeacher %d人\n", totalStudent, totalTeacher);
for (Person p : people) {
System.out.println(p.getPersonInfo());
}
scanner.close();
}
}
```
这段代码会根据输入信息构造出n个具有不同属性的对象,并输出学生和教师的人数以及每个对象的信息。
希望这个代码能够帮到您,如果您有其他问题,请随时提出。
1 Person类(抽象类): 属性:int id, String name, LocalDate birthDate。 方法:构造方法(id, name, year, month, dayOfMonth); id与birthDate的getter方法; name的getter/setter方法; 抽象方法String getPersonInfo(),该方法之所以声明为抽象是因为其在子类返回的信息与子类特有属性相关。 Student类继承自Person类: 属性:int enrollmentYear, String clazzName。 方法:构造方法(id, name, year, month, dayOfMonth, enrollmentYear, clazzName),建议使用super复用Person的构造方法; 覆盖父类的 getPersonInfo()方法,返回"Student-enrollmentYear-name" Teacher类继承自Person: 属性:String department, double salary。 方法:构造方法(id, name, year, month, dayOfMonth, department, salary),建议使用super复用Person的构造方法; 覆盖父类的 getPersonInfo()方法,返回"Teacher-department-name" main方法包含: 输入 : 产生n个对象 如果要生成Student对象则依次输入:姓名 年 月 日 入学年份 班级 如果要生成Teacher对象则依次输入:姓名 年 月 日 系 薪水 输出 : 学生人数,教师人数 n个对象getPersonNumber 输入样例: 6 Liz 1986 10 10 CS 2000 Tom 1978 5 7 CS 2500.5 Sally 2000 1 3 2018 Net01 Jerry 1988 6 7 Mechanical 1990 Eliza 2001 2 5 2019 Software02 Li 1978 5 7 cs 2400 输出样例: Teacher 4人 Student 2人 Teacher-CS-Liz Teacher-CS-Tom Student-2018-Sally Teacher-Mechanical-Jerry Student-2019-Eliza Teacher-cs-Li
好的,你的第一个问题是关于Java类的设计。根据你提供的要求,我可以给出如下的代码实现:
```java
import java.time.LocalDate;
abstract class Person {
private int id;
private String name;
private LocalDate birthDate;
public Person(int id, String name, int year, int month, int dayOfMonth) {
this.id = id;
this.name = name;
this.birthDate = LocalDate.of(year, month, dayOfMonth);
}
public int getId() {
return id;
}
public LocalDate getBirthDate() {
return birthDate;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public abstract String getPersonInfo();
}
class Student extends Person {
private int enrollmentYear;
private String clazzName;
public Student(int id, String name, int year, int month, int dayOfMonth, int enrollmentYear, String clazzName) {
super(id, name, year, month, dayOfMonth);
this.enrollmentYear = enrollmentYear;
this.clazzName = clazzName;
}
public int getEnrollmentYear() {
return enrollmentYear;
}
public String getClazzName() {
return clazzName;
}
@Override
public String getPersonInfo() {
return "Student-" + enrollmentYear + "-" + getName();
}
}
class Teacher extends Person {
private String department;
private double salary;
public Teacher(int id, String name, int year, int month, int dayOfMonth, String department, double salary) {
super(id, name, year, month, dayOfMonth);
this.department = department;
this.salary = salary;
}
public String getDepartment() {
return department;
}
public double getSalary() {
return salary;
}
@Override
public String getPersonInfo() {
return "Teacher-" + department + "-" + getName();
}
}
public class Main {
public static void main(String[] args) {
// 产生n个对象
Student s1 = new Student(1, "Liz", 1986, 10, 10, 2000, "Net01");
Student s2 = new Student(2, "Sally", 2000, 1, 3, 2018, "Software02");
Teacher t1 = new Teacher(3, "Tom", 1978, 5, 7, "CS", 2500.5);
Teacher t2 = new Teacher(4, "Jerry", 1988, 6, 7, "Mechanical", 1990);
Teacher t3 = new Teacher(5, "Eliza", 2001, 2, 5, "Software", 2019);
Teacher t4 = new Teacher(6, "Li", 1978, 5, 7, "cs", 2400);
// 输出结果
int studentCount = 0;
int teacherCount = 0;
Person[] people = new Person[]{s1, s2, t1, t2, t3, t4};
for (Person p : people) {
if (p instanceof Student) {
studentCount++;
System.out.println(p.getPersonInfo());
} else if (p instanceof Teacher) {
teacherCount++;
System.out.println(p.getPersonInfo());
}
}
System.out.println("Student " + studentCount + "人");
System.out.println("Teacher " + teacherCount + "人");
}
}
```
这个程序定义了一个抽象类 `Person`,其中包含了所有人的基本属性(id、name、birthDate),并定义了一个抽象方法 `getPersonInfo()` 来获取人的相关信息。子类 `Student` 和 `Teacher` 继承了 `Person` 类,并分别覆盖了 `getPersonInfo()` 方法,以实现自己特有的信息格式。在 `Main` 类中,通过输入参数(姓名、出生年月日、入学年份、班级或系、薪水)创建了多个 `Student` 和 `Teacher` 对象,并输出了它们的信息。同时,还统计了学生人数和教师人数。
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