UploadFilter.java

/**********************************************************************************
 * $URL: https://source.sakaiproject.org/svn/postem/trunk/postem-app/src/java/com/corejsf/UploadFilter.java $
 * $Id: UploadFilter.java 105079 2012-02-24 23:08:11Z ottenhoff@longsight.com $
 ***********************************************************************************
 *
 * Copyright (c) 2003, 2004, 2005, 2006, 2008, 2009 The Sakai Foundation
 *
 * Licensed under the Educational Community 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.opensource.org/licenses/ECL-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 com.corejsf;

import java.io.IOException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.apache.commons.fileupload.DiskFileUpload;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUpload;
import org.apache.commons.fileupload.FileUploadException;

public class UploadFilter implements Filter {
	private int sizeThreshold = -1;

	private long sizeMax = -1;

	private String repositoryPath;

	public void init(FilterConfig config) throws ServletException {
		repositoryPath = config
				.getInitParameter("com.corejsf.UploadFilter.repositoryPath");
		try {
			String paramValue = config
					.getInitParameter("com.corejsf.UploadFilter.sizeThreshold");
			if (paramValue != null)
				sizeThreshold = Integer.parseInt(paramValue);
			paramValue = config.getInitParameter("com.corejsf.UploadFilter.sizeMax");
			if (paramValue != null)
				sizeMax = Long.parseLong(paramValue);
		} catch (NumberFormatException ex) {
			ServletException servletEx = new ServletException();
			servletEx.initCause(ex);
			throw servletEx;
		}
	}

	public void destroy() {
	}

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {

		if (!(request instanceof HttpServletRequest)) {
			chain.doFilter(request, response);
			return;
		}

		HttpServletRequest httpRequest = (HttpServletRequest) request;

		boolean isMultipartContent = FileUpload.isMultipartContent(httpRequest);
		if (!isMultipartContent) {
			chain.doFilter(request, response);
			return;
		}

		DiskFileUpload upload = new DiskFileUpload();
		if (repositoryPath != null)
			upload.setRepositoryPath(repositoryPath);

		upload.setHeaderEncoding("UTF-8");
		
		try {
			List list = upload.parseRequest(httpRequest);
			final Map map = new HashMap();
			for (int i = 0; i < list.size(); i++) {
				FileItem item = (FileItem) list.get(i);
				
				if (item.isFormField()) {
				    String str = item.getString("UTF-8");
					map.put(item.getFieldName(), new String[] { str });
				} else {
					httpRequest.setAttribute(item.getFieldName(), item);
				}
			}

			chain.doFilter(new HttpServletRequestWrapper(httpRequest) {
				public Map getParameterMap() {
					return map;
				}

				// busywork follows ... should have been part of the wrapper
				public String[] getParameterValues(String name) {
					Map map = getParameterMap();
					return (String[]) map.get(name);
				}

				public String getParameter(String name) {
					String[] params = getParameterValues(name);
					if (params == null)
						return null;
					return params[0];
				}

				public Enumeration getParameterNames() {
					Map map = getParameterMap();
					return Collections.enumeration(map.keySet());
				}
			}, response);
		} catch (FileUploadException ex) {
			ServletException servletEx = new ServletException();
			servletEx.initCause(ex);
			throw servletEx;
		}
	}
}