iteratorgenerator.java

来自「webwork source」· Java 代码 · 共 104 行

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

import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

/**
 *	A bean that generates an iterator filled with a given object
 *
 *	@author Rickard 謆erg ([e-mail])
 *	@version $Revision: 1.8 $
 */
public class IteratorGenerator
   implements java.util.Iterator, webwork.action.Action
{
   // Attributes ----------------------------------------------------
   int count = 0;
   int currentCount = 0;
   String separator;
   Object value;
   List values;

   // Public --------------------------------------------------------
   public void setValues(Object aValue)
   {
      value = aValue;
   }

   public void setCount(int aCount)
   {
      this.count = aCount;
   }

   public void setSeparator(String aChar)
   {
      separator = aChar;
   }

   public boolean getHasNext()
   {
      return hasNext();
   }

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

   // Action implementation -----------------------------------------
   public String execute()
   {
      if (value==null) {
         return ERROR;
      } else {
         values = new ArrayList();
         if (separator != null)
         {
            StringTokenizer tokens = new StringTokenizer(value.toString(), separator);
            while (tokens.hasMoreTokens())
            {
               values.add(tokens.nextToken());
            }
         } else
         {
            values.add(value.toString());
         }

         // Count default is the size of the list of values
         if (count == 0)
            count = values.size();

         return SUCCESS;
      }
   }

   // Iterator implementation ---------------------------------------
   public boolean hasNext()
   {
      return (value==null) ? false : (currentCount < count || count == -1);
   }

   public Object next()
   {
      try
      {
         return values.get(currentCount%values.size());
      } finally
      {
         currentCount++;
      }
   }

   public void remove()
   {
      throw new UnsupportedOperationException("Remove is not supported in IteratorGenerator.");
   }
}