import java
.text
.DecimalFormat;
import java
.util
.*;
abstract class Person {
protected String name;
protected int age;
protected boolean gender;
public Person(String name, int age, boolean gender) {
this
.name = name;
this
.age = age;
this
.gender = gender;
}
@Override
public String
toString() {
return name + "-" + age + "-" + gender;
}
@Override
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null || getClass
() != obj
.getClass
()) return false;
Person person = (Person) obj;
return age == person
.age && gender == person
.gender &&
Objects
.equals(name, person
.name);
}
public String getName
() {
return name;
}
public int getAge
() {
return age;
}
}
class Student extends Person {
private String stuNo;
private String clazz;
public Student(String name, int age, boolean gender, String stuNo, String clazz) {
super(name, age, gender);
this
.stuNo = stuNo;
this
.clazz = clazz;
}
@Override
public String
toString() {
return "Student:" + super
.toString() + "-" + stuNo + "-" + clazz;
}
@Override
public boolean equals(Object obj) {
if (!super
.equals(obj)) return false;
Student student = (Student) obj;
return Objects
.equals(stuNo, student
.stuNo) &&
Objects
.equals(clazz, student
.clazz);
}
}
class Company {
private String name;
public Company(String name) {
this
.name = name;
}
@Override
public String
toString() {
return name;
}
@Override
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null || getClass
() != obj
.getClass
()) return false;
Company company = (Company) obj;
return Objects
.equals(name, company
.name);
}
}
class Employee extends Person {
private Company company;
private double salary;
public Employee(String name, int age, boolean gender, double salary, Company company) {
super(name, age, gender);
this
.salary = salary;
this
.company = company;
}
@Override
public String
toString() {
DecimalFormat df = new DecimalFormat("#
.#");
return "Employee:" + super
.toString() + "-" +
(company != null ? company
.toString() : "null") +
"-" + df
.format(salary);
}
@Override
public boolean equals(Object obj) {
if (!super
.equals(obj)) return false;
Employee employee = (Employee) obj;
DecimalFormat df = new DecimalFormat("#
.#");
return Double
.compare(
Double
.parseDouble(df
.format(this
.salary)),
Double
.parseDouble(df
.format(employee
.salary))) == 0 &&
Objects
.equals(company, employee
.company);
}
}
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System
.in);
List<Person> personList = new ArrayList<>
();
// 读取输入直到非s/e字符
while (scanner
.hasNext()) {
String type = scanner
.next();
if (!type
.equals("s") && !type
.equals("e")) {
break;
}
String name = scanner
.next();
int age = scanner
.nextInt
();
boolean gender = scanner
.nextBoolean
();
if (type
.equals("s")) {
String stuNo = scanner
.next();
String clazz = scanner
.next();
personList
.add(new Student(name, age, gender, stuNo, clazz));
} else {
double salary = scanner
.nextDouble
();
String companyName = scanner
.next();
Company company = companyName
.equals("null") ? null : new Company(companyName);
personList
.add(new Employee(name, age, gender, salary, company));
}
}
// 按姓名升序，姓名相同则按年龄升序排序
personList
.sort(Comparator
.comparing(Person::getName)
.thenComparingInt(Person::getAge));
// 输出排序后的所有对象
for (Person person : personList) {
System
.out
.println(person);
}
// 读取下一个输入（检查是否为exit）
if (scanner
.hasNext() && scanner
.next().equals("exit")) {
scanner
.close
();
return;
}
// 使用Set去重
Set<Student> stuSet = new LinkedHashSet<>
();
Set<Employee> empSet = new LinkedHashSet<>
();
// 分类并去重
for (Person person : personList) {
if (person instanceof Student) {
stuSet
.add((Student) person);
} else if (person instanceof Employee) {
empSet
.add((Employee) person);
}
}
// 输出分类结果
System
.out
.println("stuList");
stuSet
.forEach(System
.out::println);
System
.out
.println("empList");
empSet
.forEach(System
.out::println);
scanner
.close
();
}
}修改这段代码，这段代码答案错误
本文通过比喻解释Java中的迭代器Iterator的hasNext()方法和对象的toString()方法，以“数星星”为例，形象地阐述了如何使用迭代器遍历集合并调用对象的toString()方法进行字符串化展示。
扫一扫
901
被折叠的 条评论
为什么被折叠?
到【灌水乐园】发言
