Calculate the Surface Area and Volume of a Box With Java


The challenge

Write a function that returns the total surface area and volume of a box as an array: [area, volume]

The solution in Java

We know that the formula to calculate the area of a box is as follows:

2(h × W) + 2(h × L) + 2(W × L)

We also know that the formula to calculate the volume of a box is as follows:

W x h x H

Therefore, we can write the following code:

public class SurfaceAreaAndVolume {
    public static int[] getSize(int w,int h,int d) {
        
        int area = ((h * w)*2) + ((h * d)*2) + ((w * d)*2);
        int volume =  w*h*d;
      
        return new int[] {area, volume};
    }
}

Test cases to validate our code

It is important to have some tests to validate that our code works correctly with different inputs.

import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertArrayEquals;
import org.junit.runners.JUnit4;


public class FinalTest {

    @Test
    public void Test1() {
        assertArrayEquals(new int[] {88,48},SurfaceAreaAndVolume.getSize(4, 2, 6));
        assertArrayEquals(new int[]{6,1}, SurfaceAreaAndVolume.getSize(1, 1, 1));
        assertArrayEquals(new int[]{10,2}, SurfaceAreaAndVolume.getSize(1, 2, 1));
        assertArrayEquals(new int[]{16,4}, SurfaceAreaAndVolume.getSize(1, 2, 2));
        assertArrayEquals(new int[]{600,1000}, SurfaceAreaAndVolume.getSize(10, 10, 10));
    }
    
    @Test
    public void RandomTest() {
        Rg rg = new Rg((int) 69 * 10000);
        int x = rg.a();
        int y = rg.b();
        int z = rg.c();
        assertArrayEquals(Preloaded.getSize(x, y, z), SurfaceAreaAndVolume.getSize(x, y, z));
    }
}