1）编写接口“形状”，在其中定义静态常量PI，其值为双精度值 3.14，定义抽象方法“计算面积”“计算周长” 2）编写“形状”接口的实现类圆、长方形、三角形（属性包含底边与高） 3）编写测试类，分别创建一到两个长方形对象、圆形对象、三角形对象，计算并打印它们各自的面积和周长

首先，我们来定义一个名为`Shape`的接口，它包含静态常量`PI`和两个抽象方法：

public interface Shape {
    static final double PI = 3.14;
    
    // 抽象方法
    abstract double calculateArea();
    abstract double calculatePerimeter();
}

接下来，我们会为这个接口提供三个具体的实现类：Circle、Rectangle 和 Triangle。

1. `Circle` 类：

public class Circle implements Shape {
    private double radius;

    public Circle(double radius) {
        this.radius = radius;
    }

    @Override
    public double calculateArea() {
        return PI * Math.pow(radius, 2);
    }

    @Override
    public double calculatePerimeter() {
        return 2 * PI * radius;
    }
}

2. `Rectangle` 类：

public class Rectangle implements Shape {
    private double width;
    private double height;

    public Rectangle(double width, double height) {
        this.width = width;
        this.height = height;
    }

    @Override
    public double calculateArea() {
        return width * height;
    }

    @Override
    public double calculatePerimeter() {
        return 2 * (width + height);
    }
}

3. `Triangle` 类：

public class Triangle implements Shape {
    private double base;
    private double height;

    public Triangle(double base, double height) {
        this.base = base;
        this.height = height;
    }

    @Override
    public double calculateArea() {
        return 0.5 * base * height; // 假设这是一个等腰三角形，如果是其他类型的三角形，这里需要修改
    }

    @Override
    public double calculatePerimeter() {
        // 等腰三角形示例，实际计算取决于类型
        return base + base + Math.sqrt(Math.pow(base / 2, 2) + Math.pow(height, 2));
    }
}

最后，我们可以编写一个测试类`TestShapes`来创建和操作这些形状对象：

public class TestShapes {
    public static void main(String[] args) {
        Shape circle = new Circle(5);
        Shape rectangle = new Rectangle(4, 6);
        Shape triangle = new Triangle(3, 4);

        System.out.println("Circle Area: " + circle.calculateArea());
        System.out.println("Circle Perimeter: " + circle.calculatePerimeter());

        System.out.println("Rectangle Area: " + rectangle.calculateArea());
        System.out.println("Rectangle Perimeter: " + rectangle.calculatePerimeter());

        System.out.println("Triangle Area: " + triangle.calculateArea());
        System.out.println("Triangle Perimeter: " + triangle.calculatePerimeter());
    }
}