Empty Iterator : Iterator « Collections Data Structure « Java

1. Java
2. Collections Data Structure
3. Iterator

Empty Iterator

    

/*
 * Copyright Javelin Software, All rights reserved.
 */


import java.util.*;

/**
 * An EmptyIterator.
 *
 * @author Robin Sharp
 */

public class EmptyIterator implements Iterator 
{
    public static Iterator getInstance()
    {
        return iterator;
    }
    
    /**
     * @return false;
     */
     public boolean hasNext()
     {
        return false;
     }
     
    /**
     * @return null
     */
     public Object next()
     {
         throw new NoSuchElementException();
     }

    /**
     * No-op
     */ 
     public void remove()
     {
         throw new UnsupportedOperationException();
     }
     
     protected static Iterator iterator = new EmptyIterator();
}

   
    
    
    
  

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