这是一个相对复杂的问题,涉及到多个Java编程概念,包括面向对象编程、类的继承、多态、异常处理等。以下是我为你准备的代码:
首先,我们需要定义一个抽象类来表示形状,然后定义几个具体的形状类:
- public abstract class Shape {
- public abstract double getArea();
- }
- public class Circle extends Shape {
- private double radius;
- public Circle(double radius) {
- this.radius = radius;
- }
- @Override
- public double getArea() {
- return Math.PI * Math.pow(radius, 2);
- }
- }
- public class Rectangle extends Shape {
- private double width;
- private double height;
- public Rectangle(double width, double height) {
- this.width = width;
- this.height = height;
- }
- @Override
- public double getArea() {
- return width * height;
- }
- }
- // 其他形状类...
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然后,我们可以定义一个柱体类,它的底面积可以是任何形状:
- public class Cylinder {
- private Shape base;
- private double height;
- public Cylinder(Shape base, double height) {
- this.base = base;
- this.height = height;
- }
- public double getVolume() {
- return base.getArea() * height;
- }
- }
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接下来,我们可以定义一个广告牌类,它可以展示多个公司的广告词:
- public class Billboard {
- private Map<String, String> ads = new HashMap<>();
- public void addAd(String company, String ad) {
- ads.put(company, ad);
- }
- public void displayAds() {
- for (Map.Entry<String, String> entry : ads.entrySet()) {
- System.out.println(entry.getKey() + ": " + entry.getValue());
- }
- }
- }
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最后,我们可以定义一个学生类和一个自定义的异常类来处理年龄为负数的情况:
- public class NegativeAgeException extends Exception {
- public NegativeAgeException(String message) {
- super(message);
- }
- }
- public class Student {
- private int age;
- public Student(int age) throws NegativeAgeException {
- if (age < 0) {
- throw new NegativeAgeException("Age cannot be negative");
- }
- this.age = age;
- }
- }
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这些代码应该满足你的需求。如果你有任何问题或需要进一步的帮助,请随时告诉我!