Integer Sequence Generator : Range « Collections Data Structure « Java

1. Java
2. Collections Data Structure
3. Range

Integer Sequence Generator

      
//package org.hh.jga.util;

import java.util.Iterator;


/**
 * Integer Sequence Generator
 * 
 * @author Hong Hong
 *
 */
public abstract class Range<T extends Number> implements Iterable<T> {
  public static Range<Integer> range(int from, int to, int step) {
    return new IntRange(from, to, step);
  }
  public static Range<Integer> range(int from, int to) {
    return new IntRange(from, to, to >= from ? 1 : -1);
  }
  public static Range<Integer> range(int to) {
    return new IntRange(0, to, 1);
  }
  public static Range<Short> range(short from, short to, short step) {
    return new ShortRange(from, to, step);
  }
  public static Range<Short> range(short from, short to) {
    return new ShortRange(from, to, (short)(to >= from ? 1 : -1));
  }
  public static Range<Short> range(short to) {
    return new ShortRange((short)0, to, (short)1);
  }
  public static Range<Long> range(long from, long to, long end) {
    return new LongRange(from, to, end);
  }
  public static Range<Long> range(long from, long to) {
    return new LongRange(from, to, to >= from ? 1L : -1L);
  }
  public static Range<Long> range(Long to) {
    return new LongRange(0L, to, 1L);
  }
  protected static class IntRange extends Range<Integer> implements Iterator<Integer> {
    protected int m_cur, m_step, m_end;
    public IntRange(int from, int to, int step) {
      m_cur = from;
      m_step = step;
      m_end = to;
    }
    public boolean hasNext() {
      return m_step > 0 ? m_cur < m_end : m_end < m_cur;
    }

    public Integer next() {
      int res = m_cur;
      m_cur += m_step;
      return res;
    }

    public void remove() {
      throw new UnsupportedOperationException();
    }

    public Iterator<Integer> iterator() {
      return this;
    }
    
  }
  protected static class LongRange extends Range<Long> implements Iterator<Long> {
    protected long m_cur, m_step, m_end;
    public LongRange(long from, long to, long step) {
      m_cur = from;
      m_step = step;
      m_end = to;
    }
    public boolean hasNext() {
      return m_step > 0 ? m_cur < m_end : m_end < m_cur;
    }

    public Long next() {
      long res = m_cur;
      m_cur += m_step;
      return res;
    }

    public void remove() {
      throw new UnsupportedOperationException();
    }

    public Iterator<Long> iterator() {
      return this;
    }
  }

  protected static class ShortRange extends Range<Short> implements Iterator<Short> {
    protected short m_cur, m_step, m_end;
    public ShortRange(short from, short to, short step) {
      m_cur = from;
      m_step = step;
      m_end = to;
    }
    public boolean hasNext() {
      return m_step > 0 ? m_cur < m_end : m_end < m_cur;
    }

    public Short next() {
      short res = m_cur;
      m_cur += m_step;
      return res;
    }
    public void remove() {
      throw new UnsupportedOperationException();
    }

    public Iterator<Short> iterator() {
      return this;
    }
  }
}

   
    
    
    
    
    
  

Related examples in the same category