/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package freemarker.template;

/**
 * Used to iterate over a set of template models <em>once</em>; usually returned from
 * {@link TemplateCollectionModel#iterator()}. Note that it's not a {@link TemplateModel}.
 */
public interface TemplateModelIterator {

    /**
     * Returns the next model.
     * @throws TemplateModelException if the next model can not be retrieved
     *   (i.e. because the iterator is exhausted).
     */
    TemplateModel next() throws TemplateModelException;

    /**
     * @return whether there are any more items to iterate over.
     */
    boolean hasNext() throws TemplateModelException;
}