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/* * $Header: /home/cvs/jakarta-commons/fileupload/src/java/org/apache/commons/fileupload/FileUploadBase.java,v 1.3 2003/06/01 00:18:13 martinc Exp $ * $Revision: 1.3 $ * $Date: 2003/06/01 00:18:13 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 2001-2003 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Commons", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact apache@apache.org. * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.commons.fileupload; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; /** * <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.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: FileUploadBase.java,v 1.3 2003/06/01 00:18:13 martinc Exp $ */ public abstract class FileUploadBase { // ---------------------------------------------------------- Class methods /** * Utility method that determines whether the request contains multipart * content. * * @param req 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 req) { String contentType = req.getHeader(CONTENT_TYPE); if (contentType == null) { return false; } if (contentType.startsWith(MULTIPART)) { return true; } return false; } // ----------------------------------------------------- Manifest constants /** * HTTP content type header name. */ public static final String CONTENT_TYPE = "Content-type"; /** * HTTP content disposition header name. */ public static final String CONTENT_DISPOSITION = "Content-disposition"; /** * Content-disposition value for form data. */ public static final String FORM_DATA = "form-data"; /** * Content-disposition value for file attachment. */ public static final String ATTACHMENT = "attachment"; /** * Part of HTTP content type header. */ public static final String MULTIPART = "multipart/"; /** * HTTP content type header for multipart forms. */ public static final String MULTIPART_FORM_DATA = "multipart/form-data"; /** * HTTP content type header for multiple uploads. */ public static final String MULTIPART_MIXED = "multipart/mixed"; /** * The maximum length of a single header line that will be parsed * (1024 bytes). */ public static final int MAX_HEADER_SIZE = 1024; // ----------------------------------------------------------- Data members /** * The maximum size permitted for an uploaded file. A value of -1 indicates * no maximum. */ private long sizeMax = -1; /** * The content encoding to use when reading part headers. */ private String headerEncoding; // ----------------------------------------------------- Property accessors /** * Returns the factory class used when creating file items. * * @return The factory class for new file items. */ public abstract FileItemFactory getFileItemFactory(); /** * Sets the factory class to use when creating file items. * * @param factory The factory class for new file items. */ public abstract void setFileItemFactory(FileItemFactory factory); /** * Returns the maximum allowed upload size. * * @return The maximum allowed size, in bytes. * * @see #setSizeMax(long) * */ public long getSizeMax() { return sizeMax; } /** * Sets the maximum allowed upload size. If negative, there is no maximum. * * @param sizeMax The maximum allowed size, in bytes, or -1 for no maximum. * * @see #getSizeMax() * */ public void setSizeMax(long sizeMax) { this.sizeMax = sizeMax; } /** * Retrieves the character encoding used when reading the headers of an * individual part. When not specified, or <code>null</code>, the platform * default encoding is used. * * @return The encoding used to read part headers. */ public String getHeaderEncoding() { return headerEncoding; } /** * Specifies the character encoding to be used when reading the headers of * individual parts. When not specified, or <code>null</code>, the platform * default encoding is used. * * @param encoding The encoding used to read part headers. */ public void setHeaderEncoding(String encoding) { headerEncoding = encoding; } // --------------------------------------------------------- Public methods /** * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a> * compliant <code>multipart/form-data</code> stream. If files are stored * on disk, the path is given by <code>getRepository()</code>. * * @param req 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. * * @exception FileUploadException if there are problems reading/parsing * the request or storing files. */ public List /* FileItem */ parseRequest(HttpServletRequest req) throws FileUploadException { if (null == req) { throw new NullPointerException("req parameter"); } ArrayList items = new ArrayList(); String contentType = req.getHeader(CONTENT_TYPE); if ((null == contentType) || (!contentType.startsWith(MULTIPART))) { throw new InvalidContentTypeException("the request doesn't contain a " + MULTIPART_FORM_DATA + " or " + MULTIPART_MIXED + " stream, content type header is " + contentType); } int requestSize = req.getContentLength(); if (requestSize == -1) { throw new UnknownSizeException("the request was rejected because it's size is unknown"); } if (sizeMax >= 0 && requestSize > sizeMax) { throw new SizeLimitExceededException( "the request was rejected because " + "it's size exceeds allowed range"); } try { int boundaryIndex = contentType.indexOf("boundary="); if (boundaryIndex < 0) { throw new FileUploadException( "the request was rejected because " + "no multipart boundary was found"); } byte[] boundary = contentType.substring(boundaryIndex + 9).getBytes(); InputStream input = req.getInputStream(); MultipartStream multi = new MultipartStream(input, boundary); multi.setHeaderEncoding(headerEncoding); boolean nextPart = multi.skipPreamble(); while (nextPart) { Map headers = parseHeaders(multi.readHeaders()); String fieldName = getFieldName(headers); if (fieldName != null) { String subContentType = getHeader(headers, CONTENT_TYPE); if (subContentType != null && subContentType.startsWith(MULTIPART_MIXED)) { // Multiple files. byte[] subBoundary = subContentType.substring(subContentType.indexOf("boundary=") + 9) .getBytes(); multi.setBoundary(subBoundary); boolean nextSubPart = multi.skipPreamble(); while (nextSubPart) { headers = parseHeaders(multi.readHeaders()); if (getFileName(headers) != null) { FileItem item = createItem(headers, false); OutputStream os = item.getOutputStream(); try { multi.readBodyData(os); } finally { os.close(); } items.add(item); } else { // Ignore anything but files inside // multipart/mixed. multi.discardBodyData(); } nextSubPart = multi.readBoundary(); } multi.setBoundary(boundary); } else { if (getFileName(headers) != null) { // A single file. FileItem item = createItem(headers, false); OutputStream os = item.getOutputStream(); try { multi.readBodyData(os); } finally { os.close(); } items.add(item); } else { // A form field. FileItem item = createItem(headers, true); OutputStream os = item.getOutputStream(); try { multi.readBodyData(os); } finally { os.close(); } items.add(item); } } } else { // Skip this part. multi.discardBodyData(); } nextPart = multi.readBoundary(); } } catch (IOException e) { throw new FileUploadException( "Processing of " + MULTIPART_FORM_DATA + " request failed. " + e.getMessage()); } return items; } // ------------------------------------------------------ Protected methods /** * Retrieves the file name from the <code>Content-disposition</code> * header. * * @param headers A <code>Map</code> containing the HTTP request headers. * * @return The file name for the current <code>encapsulation</code>. */ protected String getFileName(Map /* String, String */ headers) { String fileName = null; String cd = getHeader(headers, CONTENT_DISPOSITION); if (cd.startsWith(FORM_DATA) || cd.startsWith(ATTACHMENT)) { int start = cd.indexOf("filename=\""); int end = cd.indexOf('"', start + 10); if (start != -1 && end != -1) { fileName = cd.substring(start + 10, end).trim(); } } return fileName; } /** * Retrieves the field name from the <code>Content-disposition</code> * header. * * @param headers A <code>Map</code> containing the HTTP request headers. * * @return The field name for the current <code>encapsulation</code>. */ protected String getFieldName(Map /* String, String */ headers) { String fieldName = null; String cd = getHeader(headers, CONTENT_DISPOSITION); if (cd != null && cd.startsWith(FORM_DATA)) { int start = cd.indexOf("name=\""); int end = cd.indexOf('"', start + 6); if (start != -1 && end != -1) { fieldName = cd.substring(start + 6, end); } } return fieldName; } /** * Creates a new {@link FileItem} instance. * * @param headers A <code>Map</code> containing the HTTP request * headers. * @param isFormField Whether or not this item is a form field, as * opposed to a file. * * @return A newly created <code>FileItem</code> instance. * * @exception FileUploadException if an error occurs. */ protected FileItem createItem(Map /* String, String */ headers, boolean isFormField) throws FileUploadException { return getFileItemFactory().createItem(getFieldName(headers), getHeader(headers, CONTENT_TYPE), isFormField, getFileName(headers)); } /** * <p> Parses the <code>header-part</code> and returns as key/value * pairs. * * <p> If there are multiple headers of the same names, the name * will map to a comma-separated list containing the values. * * @param headerPart The <code>header-part</code> of the current * <code>encapsulation</code>. * * @return A <code>Map</code> containing the parsed HTTP request headers. */ protected Map /* String, String */ parseHeaders(String headerPart) { Map headers = new HashMap(); char buffer[] = new char[MAX_HEADER_SIZE]; boolean done = false; int j = 0; int i; String header, headerName, headerValue; try { while (!done) { i = 0; // Copy a single line of characters into the buffer, // omitting trailing CRLF. while (i < 2 || buffer[i - 2] != '\r' || buffer[i - 1] != '\n') { buffer[i++] = headerPart.charAt(j++); } header = new String(buffer, 0, i - 2); if (header.equals("")) { done = true; } else { if (header.indexOf(':') == -1) { // This header line is malformed, skip it. continue; } headerName = header.substring(0, header.indexOf(':')).trim().toLowerCase(); headerValue = header.substring(header.indexOf(':') + 1).trim(); if (getHeader(headers, headerName) != null) { // More that one heder of that name exists, // append to the list. headers.put(headerName, getHeader(headers, headerName) + ',' + headerValue); } else { headers.put(headerName, headerValue); } } } } catch (IndexOutOfBoundsException e) { // Headers were malformed. continue with all that was // parsed. } return headers; } /** * Returns the header with the specified name from the supplied map. The * header lookup is case-insensitive. * * @param headers A <code>Map</code> containing the HTTP request headers. * @param name The name of the header to return. * * @return The value of specified header, or a comma-separated list if * there were multiple headers of that name. */ protected final String getHeader(Map /* String, String */ headers, String name) { return (String) headers.get(name.toLowerCase()); } /** * Thrown to indicate that the request is not a multipart request. */ public static class InvalidContentTypeException extends FileUploadException { /** * Constructs a <code>InvalidContentTypeException</code> with no * detail message. */ public InvalidContentTypeException() { super(); } /** * Constructs an <code>InvalidContentTypeException</code> with * the specified detail message. * * @param message The detail message. */ public InvalidContentTypeException(String message) { super(message); } } /** * Thrown to indicate that the request size is not specified. */ public static class UnknownSizeException extends FileUploadException { /** * Constructs a <code>UnknownSizeException</code> with no * detail message. */ public UnknownSizeException() { super(); } /** * Constructs an <code>UnknownSizeException</code> with * the specified detail message. * * @param message The detail message. */ public UnknownSizeException(String message) { super(message); } } /** * Thrown to indicate that the request size exceeds the configured maximum. */ public static class SizeLimitExceededException extends FileUploadException { /** * Constructs a <code>SizeExceededException</code> with no * detail message. */ public SizeLimitExceededException() { super(); } /** * Constructs an <code>SizeExceededException</code> with * the specified detail message. * * @param message The detail message. */ public SizeLimitExceededException(String message) { super(message); } } }