counter.java

来自「webwork source」· Java 代码 · 共 123 行

/*
 * WebWork, Web Application Framework
 *
 * Distributable under Apache license.
 * See terms of license at opensource.org
 */
package webwork.util;

/**
 *	A bean that can be used to keep track of a counter.
 *
 * Since it is an Iterator it can be used by the iterator tag
 *
 *	@see <related>
 *	@author Rickard 謆erg ([e-mail])
 *	@version $Revision: 1.9 $
 */
public class Counter
   implements java.util.Iterator
{
   // Attributes ----------------------------------------------------
   long first = 1;
   long current = first;
   long interval = 1;
   long last = -1;
   boolean wrap = false;

   // Public --------------------------------------------------------
   public long getNext()
   {
      long next = current;
      current+=interval;
      if (wrap && current > last)
      {
         current -= (1+last-first);
      }

      return next;
   }

   public long getPrevious()
   {
      current-=interval;
      if (wrap && current < first)
      {
         current += (last-first+1);
      }

      return current;
   }

   public long getFirst()
   {
      return first;
   }

   public long getLast()
   {
      return last;
   }

   public long getInterval()
   {
      return interval;
   }

   public boolean isWrap()
   {
      return wrap;
   }

   public void setFirst(long first)
   {
      this.first = first;
      current = first;
   }

   public void setCurrent(long current)
   {
      this.current = current;
   }

   public void setAdd(long addition)
   {
      current += addition;
   }

   public long getCurrent()
   {
      return current;
   }

   public void setInterval(long interval)
   {
      this.interval = interval;
   }

   public void setLast(long last)
   {
      this.last = last;
   }

   public void setWrap(boolean wrap)
   {
      this.wrap = wrap;
   }

   public boolean hasNext()
   {
      return last == -1 || wrap ? true : current <= last;
   }

   public Object next()
   {
      return new Long(getNext());
   }

   public void remove()
   {
      // Do nothing
   }
}