1. 第1题
public class Hello{
public static void main(String[] args){
Person[] persons = new Person[3];
persons[0] = new Person("zsq", 18, "学生");
persons[1] = new Person("zzq", 19, "大学生");
persons[2] = new Person("zqq", 25, "研究生");
for(int i = 0; i < persons.length; i++){
System.out.println(persons[i].toString());
}
bubble(persons);
System.out.println("");
for(int i = 0; i < persons.length; i++){
System.out.println(persons[i].toString());
}
}
public static void bubble(Person[] persons){
Person temp = null;
// for(int i = 0; i < objs.length; i++){
// if(objs[i] instanceof Person){
// objs[i] = (Person)objs[i];
// }
// }
for(int i = 0; i < persons.length - 1; i++){
for(int j = 0; j < persons.length - i - 1; j++){
if(persons[j].getAge() < persons[j+1].getAge()){
temp = persons[j];
persons[j] = persons[j+1];
persons[j+1] = temp;
}
}
}
}
}
class Person{
private String name;
private int age;
private String job;
public Person() {
}
public Person(String name, int age, String job) {
this.name = name;
this.age = age;
this.job = job;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getJob() {
return job;
}
public void setJob(String job) {
this.job = job;
}
@Override
public String toString() {
return "Person{" +
"name='" + name + '\'' +
", age=" + age +
", job='" + job + '\'' +
'}';
}
}
中间几道题目感觉都是一个类型的，就不做了
对于father而言：
super可以访问：name，g1()
this可以访问：id，score，f1()，this.g1()，this.name 这两个漏了
对于Son而言：
super可以访问：name, id, g1（），f1（）
this可以访问：name，g1（），show（），id，f1()，"aa”是无法访问到的，Grand的g1（）也无法访问到
Test，demo，rose，jack，john，jack、
注意john那边是因为属性没有动态绑定机制，哪里声明就在哪里使用
class Point{
double x;
double y;
public Point(double x, double y) {
this.x = x;
this.y = y;
}
}class LabeledPoint extends Point{
String label;
public LabeledPoint(String label,double x, double y){
super(x, y);
this.label = label;
}这一题太棒啦，总结得很好哦！
很简单，只要注意B的有参构造第一句隐藏了super()
这题比较综合，体现了面向对象封装，继承，多态的思想，好好做诶嘿嘿
public class Hello{
public static void main(String[] args) {
Person[] persons = new Person[4];
persons[0] = new Student("zhy", '女', 17, "001");
persons[1] = new Student("zsq", '男', 22, "002");
persons[2] = new Teacher("ljw", '女', 19, 3);
persons[3] = new Teacher("dxy", '女', 18, 2);
// bubble(persons);
for(int i = 0; i < persons.length; i++){
// System.out.println(persons[i].toString());
show(persons[i]);
}
}
public static void bubble(Person[] persons){
for(int i = 0; i < persons.length - 1; i++){
for(int j = 0; j < persons.length - 1 - i; j ++){
Person temp = null;
if(persons[j].getAge() < persons[j+1].getAge()){
temp = persons[j];
persons[j] = persons[j+1];
persons[j+1] = temp;
}
}
}
}
public static void show(Person person){
if(person instanceof Student){
((Student) person).study();
}else if(person instanceof Teacher){
((Teacher) person).teach();
}
}
}
class Person{
private String name;
private char sex;
private int age;
public Person(String name, char sex, int age) {
this.name = name;
this.sex = sex;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public char getSex() {
return sex;
}
public void setSex(char sex) {
this.sex = sex;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String play(){
return name + "爱玩";
}
public void BasicInfo(){
System.out.println("姓名：" + name + "\n年龄：" + age + "\n性别：" + sex);
}
@Override
public String toString() {
return "Person{" +
"name='" + name + '\'' +
", sex=" + sex +
", age=" + age +
'}';
}
}
class Student extends Person{
private String stu_id;
public Student(String name, char sex, int age, String stu_id) {
super(name, sex, age);
this.stu_id = stu_id;
}
public String getStu_id() {
return stu_id;
}
public void setStu_id(String stu_id) {
this.stu_id = stu_id;
}
public void study(){
System.out.println("我承诺，我会好好学习");
}
@Override
public String play() {
return super.play() + "足球";
}
public void printInfo(){
System.out.println("学生的信息：");
super.BasicInfo();
this.study();
this.play();
}
@Override
public String toString() {
return "Student{" +
"stu_id='" + stu_id + '\'' +
'}' + super.toString();
}
}
class Teacher extends Person{
private int work_age;
public Teacher(String name, char sex, int age, int work_age) {
super(name, sex, age);
this.work_age = work_age;
}
public int getWork_age() {
return work_age;
}
public void setWork_age(int work_age) {
this.work_age = work_age;
}
public void teach(){
System.out.println("我承诺，我会认真教学");
}
@Override
public String play() {
return super.play() + "象棋";
}
public void printInfo(){
System.out.println("老师的信息：");
super.BasicInfo();
this.teach();
this.play();
}
@Override
public String toString() {
return "Teacher{" +
"work_age=" + work_age +
'}' + super.toString();
}
}
