网站建设的问题分析关键词优化的建议
一、实验目的
1.掌握类的继承机制
2.掌握抽象类的定义方法
2.熟悉类中成员变量和方法的访问控制
3.熟悉成员方法或构造方法的多态性
二、实验内容
1. Circle类及其子类
【问题描述】
实现类Circle,半径为整型私有数据成员
1)构造方法:参数为半径(整型数据)。
2)成员方法:标准方法;计算周长的方法、计算面积的方法;toString()方法返回将半径、周长和面积连接的长字符串。
派生类Circle获得圆柱体类,要求:
1)添加属性成员圆柱的高(整型数据)。
2)添加标准方法、构造方法、计算圆柱体体积的方法。
定义测试类,输入半径和高,分别实例化Circle类和圆柱体类,按要求输出圆和圆柱体的信息。结果保留2位小数
【输入形式】
两行,第一行为圆类对象的半径,第二行为圆柱体类对象的半径和高
【输出形式】
两行,第一行输出圆类对象的相关信息,第二行输出圆柱体对象的相关信息
运行结果:
源码:
package circle1;import java.text.DecimalFormat;
import java.util.Scanner;public class Circle1 {public static void main(String[] args) {// TODO Auto-generated method stubScanner in = new Scanner(System.in);int rad = in.nextInt();Cir1 a1 = new Cir1(rad);a1.show();int c = in.nextInt();int h = in.nextInt();Vol a2 = new Vol(c, h);a2.show();in.close();}
}class Cir1 {private int rad;DecimalFormat df = new DecimalFormat("#.00");public double perimeter() {return Math.PI * 2 * rad;}public double area() {return rad * rad * Math.PI;}public String toString() {return "radius=" + rad + " perimeter=" + df.format(perimeter()) + " area=" + df.format(area());}public void show() {System.out.println(toString());}public Cir1(int rad) {this.rad = rad;}
}class Vol extends Cir1 {private int h;public Vol(int rad, int h) {super(rad);this.h = h;}public double volume(int h) {return area() * h;}public String toString() {return super.toString()+" volume=" + df.format(volume(h));}public void show() {System.out.printf(toString());}}
2.抽象类Shape
【问题描述】
定义抽象类Shape,圆形Circle、Rectangle为子类。
Shape类有一个数据成员(double型),定义带参构造方法、抽象方法calArea()(返回值类型:double)
在Circle、Square两个类中,实现calArea()方法。
在Rectangle类中,增加一个数据成员(double型),实现calArea()方法。
编写测试类:定义一个Shape类引用shape,分别指向一个Circle类、Rectangle类对象,利用多态,计算各平面图形的面积并输出。(结果保留2位小数)
要求:
1.数据成员全部为私有成员;
2.数据从键盘输入,调用带参构造方法创建子类对象。
提示:使用Math类的PI
【输入形式】两行:分别是为圆的半径、长方形的长和宽
【输出形式】两种平面图形的面积
运行结果:
源码:
package area;import java.text.DecimalFormat;
import java.util.Scanner;public class Area {public static void main(String[] args) {DecimalFormat df = new DecimalFormat("#.00");// TODO Auto-generated method stubScanner in = new Scanner(System.in);double a1 = in.nextDouble();Shape x1 = new Circle(a1);System.out.println(df.format(x1.calArea()));double a2 = in.nextDouble();double a3 = in.nextDouble();Shape x2 = new Rectangle(a2,a3);System.out.printf(df.format(x2.calArea()));in.close();}}
abstract class Shape{protected double rad;public Shape(double rad) {this.rad = rad;}abstract public double calArea();
}
class Circle extends Shape{public Circle(double rad) {super(rad);}public double calArea() {return Math.PI*rad*rad;}
}
class Rectangle extends Shape{private double k;public Rectangle(double c ,double k) {super(c);this.k = k;}public double calArea() {return rad*k;}
}
3. 抽象类-员工类
【问题描述】
编写抽象类-员工类,有姓名、工号(int型)、基本工资(double型)属性,计算工资为抽象方法,由员工类派生出教师、实验员和行政人员三个类。教师有课酬标准(整型,元/小时)和月课时(整型),月工资=基本工资+课酬标准月课时;实验员有月在岗小时(整型),月工资=基本工资+50每月在岗小时;行政人员有岗贴(double型),月工资=基本工资+岗贴。请编写各类定义,并编写测试类(主动类),在主动类中定义一个打印方法,形参为员工类引用,在主方法中分别创建三个对象,调用打印方法,根据不同的实参打印出不同类对象的信息。
【输入形式】
三行,第一行为教师信息,第二行为实验员信息,第三行为行政人员信息
【输出形式】
三类人员的相关信息
运行结果:
源码:
package person_inform;import java.util.Scanner;public class Person_Inform {public static void main(String[] args) {// TODO Auto-generated method stubScanner in = new Scanner(System.in);String name = in.next();int empNo = in.nextInt();double baseSalary = in.nextDouble();int hourlyFee = in.nextInt();int monthlyHour = in.nextInt();String name1 = in.next();int empNo1 = in.nextInt();double baseSalary1 = in.nextDouble();double monthlyHour1= in.nextDouble();String name2 = in.next();int empNo2 = in.nextInt();double baseSalary2 = in.nextDouble();double allowance = in.nextDouble();System.out.println("teacher:");Pers t = new Teacher(name, empNo, baseSalary, hourlyFee, monthlyHour);System.out.println(t.toString());System.out.println("lab worker:");Pers l = new lab_Worker(name1, empNo1, baseSalary1, monthlyHour1);System.out.println(l.toString());System.out.println("staff:");Pers s = new Staff(name2, empNo2, baseSalary2, allowance);System.out.println(s.toString());in.close();}}abstract class Pers {private String name;private int empNo;protected double baseSalary;public Pers(String name, int empNo, double baseSalary) {this.name = name;this.empNo = empNo;this.baseSalary = baseSalary;}abstract public double salary();public String toString() {return "name:" + name + "\n" + "empNo:" + empNo + "\n" + "baseSalary:"+ baseSalary;}}class Teacher extends Pers {private int hourlyFee;private int monthlyHour;public Teacher(String name, int empNo, double baseSalary, int hourlyFee, int monthlyHour) {super(name, empNo, baseSalary);this.hourlyFee = hourlyFee;this.monthlyHour = monthlyHour;}public double salary() {return baseSalary + hourlyFee * monthlyHour;}public String toString() {return super.toString()+"\n"+"hourlyFee:"+hourlyFee+"\n"+"monthlyHour:"+monthlyHour+"\n"+"salary:"+salary()+"\n";}}class lab_Worker extends Pers {private int monthlyHour;public lab_Worker(String name, int empNo, double baseSalary, int monthlyHour) {super(name, empNo, baseSalary);this.monthlyHour= monthlyHour;}public double salary() {return baseSalary + monthlyHour* 50;}public String toString() {return super.toString()+"\n"+"monthlyHour:"+monthlyHour+"\n"+"salary:"+salary()+"\n";}}class Staff extends Pers {private double allowance;public Staff(String name, int empNo, double baseSalary, double allowance) {super(name, empNo, baseSalary);this.allowance = allowance;}public double salary() {return baseSalary + allowance;}public String toString() {return super.toString()+"\n"+"allowance:"+allowance+"\n"+"salary:"+salary()+"\n";}
}
END:熬夜也要敲完,这是一场发际线与手速的竞争。