Java tutorial
/* * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/methods/multipart/MultipartRequestEntity.java,v 1.1 2004/10/06 03:39:59 mbecke Exp $ * $Revision: 502647 $ * $Date: 2007-02-02 17:22:54 +0100 (Fri, 02 Feb 2007) $ * * ==================================================================== * * 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. * ==================================================================== * * 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 com.android.internal.http.multipart; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.Random; import org.apache.http.Header; import org.apache.http.entity.AbstractHttpEntity; import org.apache.http.message.BasicHeader; import org.apache.http.params.HttpParams; import org.apache.http.protocol.HTTP; import org.apache.http.util.EncodingUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Implements a request entity suitable for an HTTP multipart POST method. * <p> * The HTTP multipart POST method is defined in section 3.3 of * <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC1867</a>: * <blockquote> * The media-type multipart/form-data follows the rules of all multipart * MIME data streams as outlined in RFC 1521. The multipart/form-data contains * a series of parts. Each part is expected to contain a content-disposition * header where the value is "form-data" and a name attribute specifies * the field name within the form, e.g., 'content-disposition: form-data; * name="xxxxx"', where xxxxx is the field name corresponding to that field. * Field names originally in non-ASCII character sets may be encoded using * the method outlined in RFC 1522. * </blockquote> * </p> * <p>This entity is designed to be used in conjunction with the * {@link org.apache.http.HttpRequest} to provide * multipart posts. Example usage:</p> * <pre> * File f = new File("/path/fileToUpload.txt"); * HttpRequest request = new HttpRequest("http://host/some_path"); * Part[] parts = { * new StringPart("param_name", "value"), * new FilePart(f.getName(), f) * }; * filePost.setEntity( * new MultipartRequestEntity(parts, filePost.getParams()) * ); * HttpClient client = new HttpClient(); * int status = client.executeMethod(filePost); * </pre> * * @since 3.0 */ public class MultipartEntity extends AbstractHttpEntity { private static final Log log = LogFactory.getLog(MultipartEntity.class); /** The Content-Type for multipart/form-data. */ private static final String MULTIPART_FORM_CONTENT_TYPE = "multipart/form-data"; /** * Sets the value to use as the multipart boundary. * <p> * This parameter expects a value if type {@link String}. * </p> */ public static final String MULTIPART_BOUNDARY = "http.method.multipart.boundary"; /** * The pool of ASCII chars to be used for generating a multipart boundary. */ private static byte[] MULTIPART_CHARS = EncodingUtils .getAsciiBytes("-_1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"); /** * Generates a random multipart boundary string. */ private static byte[] generateMultipartBoundary() { Random rand = new Random(); byte[] bytes = new byte[rand.nextInt(11) + 30]; // a random size from 30 to 40 for (int i = 0; i < bytes.length; i++) { bytes[i] = MULTIPART_CHARS[rand.nextInt(MULTIPART_CHARS.length)]; } return bytes; } /** The MIME parts as set by the constructor */ protected Part[] parts; private byte[] multipartBoundary; private HttpParams params; private boolean contentConsumed = false; /** * Creates a new multipart entity containing the given parts. * @param parts The parts to include. * @param params The params of the HttpMethod using this entity. */ public MultipartEntity(Part[] parts, HttpParams params) { if (parts == null) { throw new IllegalArgumentException("parts cannot be null"); } if (params == null) { throw new IllegalArgumentException("params cannot be null"); } this.parts = parts; this.params = params; } public MultipartEntity(Part[] parts) { setContentType(MULTIPART_FORM_CONTENT_TYPE); if (parts == null) { throw new IllegalArgumentException("parts cannot be null"); } this.parts = parts; this.params = null; } /** * Returns the MIME boundary string that is used to demarcate boundaries of * this part. The first call to this method will implicitly create a new * boundary string. To create a boundary string first the * HttpMethodParams.MULTIPART_BOUNDARY parameter is considered. Otherwise * a random one is generated. * * @return The boundary string of this entity in ASCII encoding. */ protected byte[] getMultipartBoundary() { if (multipartBoundary == null) { String temp = null; if (params != null) { temp = (String) params.getParameter(MULTIPART_BOUNDARY); } if (temp != null) { multipartBoundary = EncodingUtils.getAsciiBytes(temp); } else { multipartBoundary = generateMultipartBoundary(); } } return multipartBoundary; } /** * Returns <code>true</code> if all parts are repeatable, <code>false</code> otherwise. */ public boolean isRepeatable() { for (int i = 0; i < parts.length; i++) { if (!parts[i].isRepeatable()) { return false; } } return true; } /* (non-Javadoc) */ public void writeTo(OutputStream out) throws IOException { Part.sendParts(out, parts, getMultipartBoundary()); } /* (non-Javadoc) * @see org.apache.commons.http.AbstractHttpEntity.#getContentType() */ @Override public Header getContentType() { StringBuffer buffer = new StringBuffer(MULTIPART_FORM_CONTENT_TYPE); buffer.append("; boundary="); buffer.append(EncodingUtils.getAsciiString(getMultipartBoundary())); return new BasicHeader(HTTP.CONTENT_TYPE, buffer.toString()); } /* (non-Javadoc) */ public long getContentLength() { try { return Part.getLengthOfParts(parts, getMultipartBoundary()); } catch (Exception e) { log.error("An exception occurred while getting the length of the parts", e); return 0; } } public InputStream getContent() throws IOException, IllegalStateException { if (!isRepeatable() && this.contentConsumed) { throw new IllegalStateException("Content has been consumed"); } this.contentConsumed = true; ByteArrayOutputStream baos = new ByteArrayOutputStream(); Part.sendParts(baos, this.parts, this.multipartBoundary); ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray()); return bais; } public boolean isStreaming() { return false; } }