/*
 * 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 org.apache.wicket.util.upload;

import java.io.IOException;


/**
 * An iterator, as returned by {@link FileUploadBase#getItemIterator(RequestContext)}.
 */
public interface FileItemIterator
{
	/**
	 * Returns, whether another instance of {@link FileItemStream} is available.
	 * 
	 * @throws FileUploadException
	 *             Parsing or processing the file item failed.
	 * @throws IOException
	 *             Reading the file item failed.
	 * @return True, if one or more additional file items are available, otherwise false.
	 */
	boolean hasNext() throws FileUploadException, IOException;

	/**
	 * Returns the next available {@link FileItemStream}.
	 * 
	 * @throws java.util.NoSuchElementException
	 *             No more items are available. Use {@link #hasNext()} to prevent this exception.
	 * @throws FileUploadException
	 *             Parsing or processing the file item failed.
	 * @throws IOException
	 *             Reading the file item failed.
	 * @return FileItemStream instance, which provides access to the next file item.
	 */
	FileItemStream next() throws FileUploadException, IOException;
}
