2024秋面向对象程序设计-实验二(接口与异常)

6.1

Scanner sc=new Scanner(System.in);

int n=sc.nextInt();

String x=sc.next();

starter=new MyStarter(new ActionListener(){

public void actionPerformed(ActionEvent e){

for(int i=0;i<n;i++){

System.out.println(x);

}

System.out.println(this.getClass().getName());

System.out.println(Arrays.toString(this.getClass().getInterfaces()));

}

});

 

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6.2

 

class RTriangle implements IShape{

private double a;

private double b;

public double getArea(){

return 0.5*a*b;

}

public double getPerimeter(){

return a+b+Math.sqrt(a*a+b*b);

}

public RTriangle(double a, double b){

this.a=a;

this.b=b;

}

}

 

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6.3

 

 

abstract class GeometricObject implements Comparable<GeometricObject>{

public abstract double getArea();

@Override

public int compareTo(GeometricObject o) {

if (this.getArea() > o.getArea()) {

return 1;

} else if (this.getArea() < o.getArea()) {

return -1;

} else {

return 0;

}

}

public static GeometricObject max(GeometricObject o1, GeometricObject o2){

return o1.compareTo(o2)>=0?o1:o2;

}

}

class Circle extends GeometricObject{

private double radius;

public Circle(double radius){

this.radius = radius;

}

public double getArea(){

return Math.PI * radius * radius;

}

public double getRadius() {

return radius;

}

@Override

public String toString() {

return "Circle " +

"radius = " + radius ;

}

}

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6.4

 

import java.util.*;

abstract class Mammal{

private String name;

abstract void makeSound();

public String getName(){

return name;

}

public void setName(String a){

this.name=a;

}

}

interface CanJump{

void jump();

}

class Dog extends Mammal implements CanJump{

public Dog(String a){

super.s