Applying static keyword to a class in java : <p>My problem is regarding the application of Static keyword for a class. 
As it is easy to apply static keyword for instance variables and methods but
while coming to classes it is not working.
finally please help me to solve the code</p>

<pre><code>static class Box{
    static int width,depth,height;
    static void volume(int w,int d,int h){
        double vol=w*d*h;
        System.out.println(vol);
    }
}

class ClassStaticTest{
    public static void main(String[] args){
        //Box b=new Box();
        width=10;
        height=10;
        depth=10;
        Box.volume(10,10,10);
    }
}
</code></pre>
