/*
* FreeMarker: a tool that allows Java programs to generate HTML
* output using templates.
* Copyright (C) 1998-2004 Benjamin Geer
* Email: beroul@users.sourceforge.net
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
package freemarker.template;
import java.util.ConcurrentModificationException;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;
/**
* Iterator class for {@link FastList} where the underlying Collection is a
* List. Note that this model is <em>not</em> serializable, to match the
* semantics of the underlying <code>java.util.ListIterator</code>.
*
* @version $Id: FastListIterator.java 1087 2005-08-28 12:37:29Z run2000 $
* @see FastList
* @since 1.8
*/
public class FastListIterator implements TemplateWriteableIteratorModel {
/** The iterator being wrapped by this model. */
protected final ListIterator iterator;
/**
* Constructor that takes a <code>java.util.Collection</code> implementation
* to iterator over.
*
* @throws NullPointerException
* the collection is null
*/
public FastListIterator(List list) {
iterator = list.listIterator();
}
/**
* Do we have another item in the list?
*
* @return <code>true</code> if there are more items to be iterated over,
* otherwise <code>false</code>
* @throws TemplateModelException
* there was a problem determining the next item in the list
*/
public boolean hasNext() throws TemplateModelException {
return iterator.hasNext();
}
/**
* Retrieve the next item in the list. The item will be a
* <code>TemplateModel</code> containing the underlying value.
*
* @return the next item in the list
* @throws TemplateModelException
* the next item couldn't be retrieved, or we're at the end of
* the list
*/
public TemplateModel next() throws TemplateModelException {
try {
return (TemplateModel) iterator.next();
} catch (NoSuchElementException e) {
throw new TemplateModelException("No more elements", e);
} catch (ClassCastException e) {
throw new TemplateModelException("Element is not a TemplateModel", e);
} catch (ConcurrentModificationException e) {
throw new TemplateModelException("List has been structurally modified", e);
}
}
/**
* Inserts the specified element into the list. The element is inserted
* immediately before the next element that would be returned by next, if
* any.
*
* @param model
* the model to insert into the list
* @throws TemplateModelException
* the model could not be assigned to the list
*/
public void set(TemplateModel model) throws TemplateModelException {
iterator.set(model);
}
/**
* Is the object empty?
*
* @return <code>true</code> if this object is empty, otherwise
* <code>false</code>
*/
public boolean isEmpty() throws TemplateModelException {
return iterator == null;
}
}