NumberRange.java

package javatest;

import com.google.common.collect.AbstractIterator;
import com.google.common.collect.BoundType;
import com.google.common.collect.DiscreteDomains;
import com.google.common.collect.Ranges;

import java.util.Iterator;

import static com.google.common.base.Preconditions.checkArgument;

public class NumberRange
{
    public static void main(String[] args)
    {
        for (Long n : rangesRange(0, 10)) {
            System.out.println(n);
        }
        System.out.println();

        for (Long n : iteratorRange(0, 10)) {
            System.out.println(n);
        }
        System.out.println();
    }

    private static Iterable<Long> rangesRange(long start, long end)
    {
        return Ranges.range(start, BoundType.CLOSED, end, BoundType.OPEN).asSet(DiscreteDomains.longs());
    }

    public static Iterable<Long> iteratorRange(final long start, final long end)
    {
        checkArgument(start <= end, "start is greater than end");

        return new Iterable<Long>()
        {
            public Iterator<Long> iterator()
            {
                return new AbstractIterator<Long>()
                {
                    private long n = start;

                    @Override
                    protected Long computeNext()
                    {
                        if (n == end) {
                            return endOfData();
                        }
                        return n++;
                    }
                };
            }
        };
    }
}