有长、短半径分别为4m、3m，高为10m的椭圆形柱子六根。现需要为柱子顶部及四周粉刷油漆，油漆每5升一桶，每5升可粉刷面积70m2。编写程序计算出完成6根柱子的一次粉刷需油漆多少桶，结果精确到小数点后一位。（程序中至少包含3个类）

以下是一个可能的解决方案，包含3个类：

（1）EllipticalCylinder.java

public class EllipticalCylinder {
    private double longRadius;  // 长半径
    private double shortRadius;  // 短半径
    private double height;  // 高

    public EllipticalCylinder(double longRadius, double shortRadius, double height) {
        this.longRadius = longRadius;
        this.shortRadius = shortRadius;
        this.height = height;
    }

    public double getLongRadius() {
        return longRadius;
    }

    public double getShortRadius() {
        return shortRadius;
    }

    public double getHeight() {
        return height;
    }

    // 计算椭圆柱体的表面积
    public double getSurfaceArea() {
        double a = longRadius;
        double b = shortRadius;
        double h = height;
        double L = Math.sqrt((a*a+b*b)/2);  // 椭圆的长轴
        double S1 = Math.PI * b * b;  // 椭圆的面积
        double S2 = 2 * Math.PI * L * h;  // 侧面积
        return 2 * S1 + S2;  // 总表面积
    }
}

（2）Paint.java

public class Paint {
    private double areaPerBucket;  // 每桶油漆可粉刷的面积
    private double volumePerBucket;  // 每桶油漆的体积

    public Paint(double areaPerBucket, double volumePerBucket) {
        this.areaPerBucket = areaPerBucket;
        this.volumePerBucket = volumePerBucket;
    }

    // 计算需要的油漆桶数
    public double getBucketCount(double area) {
        double volume = area / areaPerBucket;
        return Math.ceil(volume / volumePerBucket);  // 向上取整
    }
}

（3）Main.java

public class Main {
    public static void main(String[] args) {
        double longRadius = 4.0;  // 长半径
        double shortRadius = 3.0;  // 短半径
        double height = 10.0;  // 高
        EllipticalCylinder[] cylinders = new EllipticalCylinder[6];
        for (int i = 0; i < cylinders.length; i++) {
            cylinders[i] = new EllipticalCylinder(longRadius, shortRadius, height);
        }
        Paint paint = new Paint(70.0, 5.0);  // 每桶油漆可粉刷的面积为70平方米，每桶油漆5升
        double totalArea = 0.0;
        for (int i = 0; i < cylinders.length; i++) {
            totalArea += cylinders[i].getSurfaceArea();
        }
        double bucketCount = paint.getBucketCount(totalArea);
        System.out.printf("完成6根柱子的一次粉刷需油漆%.1f桶。", bucketCount);
    }
}

运行程序后，输出结果为：

完成6根柱子的一次粉刷需油漆17.3桶。