Random value from enum with probability

Question

I have an enum that I would like to randomly select a value from, but not truly random. I would like some of the values to be less likely of being selected so far. Here is

Answer 1

import java.util.*;
enum R {
    a(.1),b(.2),c(.3),d(.4);
    R(final double p) {
        this.p=p;
    }
    private static void init() {
        sums=new double[values().length+1];
        sums[0]=0;
        for(int i=0;i bins=new EnumMap(R.class);
        for(R r:R.values())
            bins.put(r,0);
        final int n=1000000;
        for(int i=0;i