ServletFileUpload.java

/*
 * 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.t2framework.confeito.apache.commons.fileupload.servlet;

import java.io.IOException;
import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.t2framework.confeito.apache.commons.fileupload.FileItem;
import org.t2framework.confeito.apache.commons.fileupload.FileItemFactory;
import org.t2framework.confeito.apache.commons.fileupload.FileItemIterator;
import org.t2framework.confeito.apache.commons.fileupload.FileUpload;
import org.t2framework.confeito.apache.commons.fileupload.FileUploadException;

/**
 * <p>
 * High level API for processing file uploads.
 * </p>
 * 
 * <p>
 * This class handles multiple files per single HTML widget, sent using
 * <code>multipart/mixed</code> encoding type, as specified by <a
 * href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>. Use
 * {@link #parseRequest(HttpServletRequest)} to acquire a list of
 * {@link org.t2framework.confeito.apache.commons.fileupload.FileItem}s
 * associated with a given HTML widget.
 * </p>
 * 
 * <p>
 * How the data for individual parts is stored is determined by the factory used
 * to create them; a given part may be in memory, on disk, or somewhere else.
 * </p>
 * 
 * @author <a href="mailto:Rafal.Krzewski@e-point.pl">Rafal Krzewski</a>
 * @author <a href="mailto:dlr@collab.net">Daniel Rall</a>
 * @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
 * @author <a href="mailto:jmcnally@collab.net">John McNally</a>
 * @author <a href="mailto:martinc@apache.org">Martin Cooper</a>
 * @author Sean C. Sullivan
 * 
 * @version $Id: ServletFileUpload.java 479484 2006-11-27 01:06:53Z jochen $
 */
public class ServletFileUpload extends FileUpload {

	// ---------------------------------------------------------- Class methods

	/**
	 * Utility method that determines whether the request contains multipart
	 * content.
	 * 
	 * @param request
	 *            The servlet request to be evaluated. Must be non-null.
	 * 
	 * @return <code>true</code> if the request is multipart; <code>false</code>
	 *         otherwise.
	 */
	public static final boolean isMultipartContent(HttpServletRequest request) {
		if (!"post".equals(request.getMethod().toLowerCase())) {
			return false;
		}
		String contentType = request.getContentType();
		if (contentType == null) {
			return false;
		}
		if (contentType.toLowerCase().startsWith(MULTIPART)) {
			return true;
		}
		return false;
	}

	// ----------------------------------------------------------- Constructors

	/**
	 * Constructs an uninitialised instance of this class. A factory must be
	 * configured, using <code>setFileItemFactory()</code>, before attempting to
	 * parse requests.
	 * 
	 * @see FileUpload#FileUpload(FileItemFactory)
	 */
	public ServletFileUpload() {
		super();
	}

	/**
	 * Constructs an instance of this class which uses the supplied factory to
	 * create <code>FileItem</code> instances.
	 * 
	 * @see FileUpload#FileUpload()
	 * @param fileItemFactory
	 *            The factory to use for creating file items.
	 */
	public ServletFileUpload(FileItemFactory fileItemFactory) {
		super(fileItemFactory);
	}

	// --------------------------------------------------------- Public methods

	/**
	 * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
	 * compliant <code>multipart/form-data</code> stream.
	 * 
	 * @param request
	 *            The servlet request to be parsed.
	 * 
	 * @return A list of <code>FileItem</code> instances parsed from the
	 *         request, in the order that they were transmitted.
	 * 
	 * @throws FileUploadException
	 *             if there are problems reading/parsing the request or storing
	 *             files.
	 */
	public List<FileItem> parseRequest(HttpServletRequest request)
			throws FileUploadException {
		return parseRequest(new ServletRequestContext(request));
	}

	/**
	 * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
	 * compliant <code>multipart/form-data</code> stream.
	 * 
	 * @param request
	 *            The servlet request to be parsed.
	 * 
	 * @return An iterator to instances of <code>FileItemStream</code> parsed
	 *         from the request, in the order that they were transmitted.
	 * 
	 * @throws FileUploadException
	 *             if there are problems reading/parsing the request or storing
	 *             files.
	 * @throws IOException
	 *             An I/O error occurred. This may be a network error while
	 *             communicating with the client or a problem while storing the
	 *             uploaded content.
	 */
	public FileItemIterator getItemIterator(HttpServletRequest request)
			throws FileUploadException, IOException {
		return super.getItemIterator(new ServletRequestContext(request));
	}
}