Generate all configurations of balls in bins, optionally with limited capacity

BallsInBins.java

import java.util.function.Consumer;

public class BallsInBins {
    public static void traverseConfigurations (int nballs,int nbins,Consumer<int []> consumer) {
        traverseConfigurations(nballs,nbins,Integer.MAX_VALUE,consumer);
    }
    
    public static void traverseConfigurations (int nballs,int nbins,int capacity,Consumer<int []> consumer) {
        recurse (new int [nbins],nballs,capacity,0,consumer);
    }
    
    private static void recurse(int [] bins,int nballs,int capacity,int index,Consumer<int []> consumer) {
        if (index == bins.length - 1) {
            if (nballs <= capacity) {
                bins [bins.length - 1] = nballs;
                consumer.accept(bins);
            }
        }
        else
            for (bins [index] = 0;bins [index] <= nballs && bins [index] <= capacity;bins [index]++)
                recurse (bins,nballs - bins [index],capacity,index + 1,consumer);
    }
}