4.编程题 (1)设计一个名为Geometric的几何图形的抽象类，该类包括： 1设计一个名为Triangle的三角形类来实现CGcometric类，该类包括。 0三个名为sidel.side2和side的double属性表示三角形的三条边。 2一个无参构造方法创建三角形。 一个能创建指定sidel、side2和side3的矩形的构造方法。 1 sidel、side2和side3的访问器方法。 6一个名为getArea()的方法，返回该三角形的面积。 ⑥一个名为getPerimeter()的方法，返回该三角形的周长。 2一个名为isTriangle()的方法，判断三边是否能构成三角形。 8一个名为toString()的方法，返回三边较小的字符串描述。(5)编写测试类，测试图形的面积和周长。

下面是对应的Java代码：

Geometric.java

public abstract class Geometric {
    protected String color;
    protected boolean filled;
    
    public Geometric() {}
    
    public Geometric(String color, boolean filled) {
        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) {
        this.filled = filled;
    }
    
    public abstract double getArea();
    
    public abstract double getPerimeter();
    
    public String toString() {
        return "Geometric[color=" + color + ", filled=" + filled + "]";
    }
}

Triangle.java

public class Triangle extends Geometric {
    private double side1;
    private double side2;
    private double side3;
    
    public Triangle() {}
    
    public Triangle(double side1, double side2, double side3) {
        this.side1 = side1;
        this.side2 = side2;
        this.side3 = side3;
    }
    
    public Triangle(double side1, double side2, double side3, String color, boolean filled) {
        super(color, filled);
        this.side1 = side1;
        this.side2 = side2;
        this.side3 = side3;
    }
    
    public double getSide1() {
        return side1;
    }
    
    public void setSide1(double side1) {
        this.side1 = side1;
    }
    
    public double getSide2() {
        return side2;
    }
    
    public void setSide2(double side2) {
        this.side2 = side2;
    }
    
    public double getSide3() {
        return side3;
    }
    
    public void setSide3(double side3) {
        this.side3 = side3;
    }
    
    public boolean isTriangle() {
        return side1 + side2 > side3 && side1 + side3 > side2 && side2 + side3 > side1;
    }
    
    public double getArea() {
        double p = (side1 + side2 + side3) / 2;
        return Math.sqrt(p * (p - side1) * (p - side2) * (p - side3));
    }
    
    public double getPerimeter() {
        return side1 + side2 + side3;
    }
    
    public String toString() {
        double[] sides = {side1, side2, side3};
        Arrays.sort(sides);
        return "Triangle[" + super.toString() + ", side1=" + sides[0] + ", side2=" + sides[1] + ", side3=" + sides[2] + "]";
    }
}

Test.java

public class Test {
    public static void main(String[] args) {
        Geometric g1 = new Circle(5, "red", true);
        System.out.println(g1);
        System.out.println("Area: " + g1.getArea());
        System.out.println("Perimeter: " + g1.getPerimeter());
        
        Geometric g2 = new Rectangle(3, 4, "blue", false);
        System.out.println(g2);
        System.out.println("Area: " + g2.getArea());
        System.out.println("Perimeter: " + g2.getPerimeter());
        
        Geometric g3 = new Triangle(3, 4, 5, "green", true);
        System.out.println(g3);
        System.out.println("Area: " + g3.getArea());
        System.out.println("Perimeter: " + g3.getPerimeter());
        System.out.println("Is triangle: " + ((Triangle) g3).isTriangle()));
    }
}

注意：此处的测试代码只是示例，具体的测试代码根据实际情况进行编写。