protected int resourceCompare(Resource foo, Resource bar) {
        return (int) (foo.getLastModified() - bar.getLastModified());
    }

When difference foo.getLastModified() - bar.getLastModified() is greater than
Integer.MAX_VALUE or less than Integer.MIN_VALUE, result returned by
resourceCompare is undefined. Possible fix is:

    protected int resourceCompare(Resource foo, Resource bar) {
        long diff = foo.getLastModified() - bar.getLastModified();
        if (diff > 0) {
            return +1;
        } else if (diff < 0) {
            return -1;
        } else {
            return 0;
        }
    }