Java课程第三次实验报告
\1. 在前面实验二已定义的学生类Student的基础上，以Student类为父类，为学生类派生出一个子类为大学生类（CollegeStudent）。
CollegeStudent 类在学生类上增加一个专业（profession）数据属性；方法上增加获得专业和设置专业两个方法。并对超类中的toString( )方法进行重写，使得CollegeStudent类中的toString( )方法除了显示学生类的信息外，还要显示它的专业属性。
编写测试程序的主类。在主类中创建一个Student对象和CollegeStudent对象，并显示或修改这两个对象的属性值。
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package student ;
public class Student {
private int UID;
private String name;
private Boolean gender;
private int age;
static int cnt ;
public Student() {}
public Student(int UID,String name,Boolean gender,int age) {
cnt ++ ;
this.UID = UID;
this.name = name;
this.gender = gender;
this.age = age;
}
public int getAge() {
return age;
}
public String getName() {
return name;
}
public Boolean getGender() {
return gender;
}
public int getUID() {
return UID;
}
public void setAge(int age) {
this.age = age;
}
public void setUID(int uID) {
UID = uID;
}
public void setName(String name) {
this.name = name;
}
public void setGender(Boolean gender) {
this.gender = gender;
}
@Override
protected void finalize() throws Throwable {
System.out.println("对象已被销毁");;
}
@Override
public String toString() {
if (gender) return "该同学的学号为：" + UID +"，姓名叫：" + name + "，性别：男" + "，年龄：" + age;
return "该同学的学号为：" + UID +"，姓名叫：" + name + "，性别：女" + "，年龄：" + age;
}
public static int getCnt() {
return cnt;
}
}
class CollegeStudent extends Student{
private String profession;
CollegeStudent(int studentID, String name, Boolean sex, int age, String profession) {
super( studentID, name, sex, age );
this.profession = profession;
}
public String getProfession() {
return profession;
}
public void setProfession(String profession) {
this.profession = profession;
}
@Override
public String toString() {
return "CollegeStudent{" +
"profession='" + profession + '\'' +
"studentID='" + super.getUID() + '\'' +
", name='" + super.getName() + '\'' +
", sex='" + super.getGender() + '\'' +
", age=" + super.getAge() +
'}';
}
}
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- 设计一个人员类（Person），其中包含一个方法pay，代表人员的工资支出。再从Person类派生出助教类（Assistant）、讲师类（Instructor）、副教授类（Assistant Professor）和教授类（Professor）。其中：工资支出=基本工资+授课时数*每课时兼课金。
但助教基本工资为800，每课时兼课金25，讲师基本工资为1000，每课时兼课金35，
副教授基本工资为1200，每课时兼课金40，教授基本工资为1400，每课时兼课金50。
1.将Person定义为抽象类，pay为抽象方法，设计程序实现多态性。
2.将Person定义为接口，设计程序实现多态性。
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class Person {
public int basic;
public int hour;
public int charge;
public Person() {
}
public Person(int basic, int charge) {
this.basic = basic;
this.charge = charge;
}
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (basic + hour * charge) );
}
}
class Assistant extends Person {
public Assistant() {
super( 800, 25 );
}
}
class Instructor extends Person {
public Instructor() {
super( 1000, 35 );
}
}
class AssistantProfessor extends Person {
public AssistantProfessor() {
super( 1200, 40 );
}
}
class Professor extends Person {
public Professor() {
super( 1400, 50 );
}
}
abstract class Person {
public int hour;
public abstract void pay(int hour);
class Assistant extends Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (800 + hour * 25) );
}
}
class Instructor extends Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1000 + hour * 35) );
}
}
class AssistantProfessor extends Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1200 + hour * 40) );
}
}
class Professor extends Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1400 + hour * 50) );
}
}
interface Person {
void pay(int hour);
}
class Assistant implements Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (800 + hour * 25) );
}
}
class Instructor implements Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1000 + hour * 35) );
}
}
class AssistantProfessor implements Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1200 + hour * 40) );
}
}
class Professor implements Person {
@Override
public void pay(int hour) {
System.out.println( hour + "小时后的工资为" + (1400 + hour * 50) );
}
}
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- 从键盘输入两个数，进行相除，显示商。当输入串中含有非数字时或除数为0时，通过异常处理机制，使程序能正确运行。
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| import java.util.InputMismatchException;
import java.util.Scanner;
public class yichang {
public static void main(String[] args) {
try {
Scanner scanner = new Scanner(System.in);
System.out.print( "请输入除数:" );
int dividedNum = scanner.nextInt();
System.out.print( "请输入被除数:" );
int divNum = scanner.nextInt();
System.out.println( "计算结果：" + dividedNum / divNum );
} catch (InputMismatchException e1) {
System.out.println("输入不为数字!");
}catch (ArithmeticException e2) {
System.out.println("不能除0!");
}
}
}
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