实验指导书：实验7--继承与多态(一)(共14页).docx

精选优质文档-----倾情为你奉上西 安 邮 电 大 学（计算机学院）面向对象程序设计JAVA课内实验报告实验名称: 继承与多态（一）专业名称: 软件工程班 级: 软件1501学生姓名:冀潘婷学号（8位）:指导教师:张德慧实验时间:2016.10.21一. 实验目的及实验环境 1理解子类、父类的概念，掌握子类继承父类的方法 2理解成员变量的隐藏和方法重写 3会使用super关键字操作被隐藏的成员变量和方法 4了解final类和final方法的作用 5理解protected修饰符的作用和用法二. 实验内容 1 基本内容（实验前请及时熟悉如下相关内容）1）类的继承：定义子类2）使用super关键字调用父类方法3）方法覆盖overriding：覆盖Object类的toString( )方法4）练习使用ArrayList类的方法5）练习覆盖Object类的equals( )方法 2 综合实验：2.1 (Y. Daniel Liang英文版八版P403：11.1) (The Triangle class) Design a class named Triangle that extends GeometricObject. The class contains:■ Three double data fields named side1, side2, and side3 with default values 1.0 to denote three sides of the triangle.■ A no-arg constructor that creates a default triangle.■ A constructor that creates a triangle with the specified side1, side2, and side3.■ The accessor methods for all three data fields.■ A method named getArea() that returns the area of this triangle.■ A method named getPerimeter() that returns the perimeter of this triangle.■ A method named toString() that returns a string description for the triangle.For the formula to compute the area of a triangle, see Exercise 2.21. The toString() method is implemented as follows:return "Triangle: side1 = " + side1 + " side2 = " + side2 + " side3 = " + side3;Draw the UML diagram for the classes Triangle and GeometricObject.Implement the class. Write a test program that creates a Triangle object with sides 1, 1.5, 1, color yellow and filled true, and displays the area, perimeter, color, and whether filled or not. （不要求画出UML图）2.2 (Y. Daniel Liang英文版八版P403：11.2) (The Person, Student, Employee, Faculty, and Staff classes) Design a class named Person and its two subclasses named Student and Employee.Make Faculty and Staff subclasses of Employee. A person has a name, address, phone number, and email address. A student has a class status (freshman, sophomore, junior, or senior). Define the status as a constant. An employee has an office, salary, and date hired. Define a class named MyDate that contains the fields year, month, and day. A faculty member has office hours and a rank. A staff member has a title. Override the toString method in each class to display the class name and the person’s name.Draw the UML diagram for the classes. Implement the classes. Write a test programthat creates a Person, Student, Employee, Faculty, and Staff, and invokes their toString() methods. （不要求画出UML图）2.3 (Y. Daniel Liang英文版八版P404：11.5) (The Course class) Rewrite the Course class in Listing 10.6. Use an ArrayList to replace an array to store students. You should not change the original contract of the Course class (i.e., the definition of the constructors and methods should not be changed).3． 测试数据及运行结果4． 源代码5． （1）.package eightWeek;public class dfg { public static void main(String[] args) { // TODO Auto-generated method stub Triangle triangle = new Triangle(1,1.5,1,"yellow",true); System.out.println("The triangle of Area:"+triangle.getArea()); System.out.println("The triangle of perimeter:"+triangle.getPerimeter()); System.out.println("color:"+triangle.getColor()); System.out.println("color is filled or not?"+triangle.isFilled()); }} class Triangle extends GeometricObject{ double side1=1.0; double side2=1.0; double side3=1.0; public Triangle(double side1,double side2,double side3){ this.side1=side1; this.side2=side2; this.side3=side3; } public double Getside1(){ return side1; } public double Getside2(){ return side2; } public double Getside3(){ return side3; } public double getPerimeter() { return this.side1 + this.side2 + this.side3; } public double getArea() { double p = this.getPerimeter() / 2; double ss = p * (p - this.side1) * (p - this.side2) * (p - this.side3); double s = Math.sqrt(ss); return s; } public Triangle(double side1, double side2,double side3,String color, boolean filled){ this.side1=side1; this.side2=side2; this.side3=side3; this.color=color; super.setFilled(filled); } public String getString() { return "Triangle：" + this.side1 + "," + this.side2 + "," + this.side3; }} class GeometricObject{ public String color="white"; public boolean filled; public java.util.Date dateCreated; GeometricObject(){ } public GeometricObject(String color,boolean filled){ dateCreated = new java.util.Date(); this.color=color; this.filled=filled; } public String getColor(){ return color; } public void setColor(String color){ this.color=color; } public boolean isFilled(){ return filled; } public void setFilled(boolean filled){。