Range ohne Listen

import java.util.*;

public class Range implements Iterable<Integer> {
	private final int begin, end, stride;

	public Range(int begin, int end, int stride) throws Exception {
		this.begin = begin;
		this.end = end;
		if (stride > 0) {
			this.stride = stride;
		} else {
			throw new Exception("stride muss größer als 0 sein!");
		}
	}

	public Range(int begin, int end) {
		this.begin = begin;
		this.end = end;
		this.stride = 1;

	}

	public int getEnd() {
		return end;
	}

	public int getStride() {
		return stride;
	}

	public int getBegin() {
		return begin;
	}

	@Override
	public Iterator<Integer> iterator() {
		return new RangeIterator();
	}

	class RangeIterator implements Iterator<Integer> {
		private int current = begin;
		private boolean b = true;

		@Override
		public boolean hasNext() {
			if (begin == end)
				return b;
			if (begin > end)
				return (end <= current);
			if (begin < end)
				return (end >= current);
			return false;
		}

		@Override
		public Integer next() {
			int c = current;
			if (!hasNext())
				throw new NoSuchElementException("keine Elemente mehr!");
			if (begin < end)
				current = current + stride;
			if (begin > end)
				current = current - stride;
			if (begin == end)b=false;
			return c;
		}

	}

	public static void main(String[] args) throws Exception {
		Range r = new Range(100000,0, 1);
		for (Integer in : r) {
			System.out.println(in);
		}

	}

}