Problem Decomposition: Play "Spot the Objects!"

// Class to run the simulation:

public class ______________________ {
    
    public static void main(String[] args) {

    }

}

// Thing1 that spews forth boxes

class _______________ { 

} 

// Thing2 that boxes fall into

class _______________ { 

}    

// Thing3 who unloads from Thing2 and loads boxes into Thing4

class _______________ { 

}

// Thing4 into which Thing3 loads boxes

class _______________ {

}

// Do we need a class for Boxes? Use variables instead?