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Diffstat (limited to 'src/org/apache/http/impl/entity/StrictContentLengthStrategy.java')
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1 files changed, 220 insertions, 0 deletions
diff --git a/src/org/apache/http/impl/entity/StrictContentLengthStrategy.java b/src/org/apache/http/impl/entity/StrictContentLengthStrategy.java new file mode 100644 index 0000000..30be8e2 --- /dev/null +++ b/src/org/apache/http/impl/entity/StrictContentLengthStrategy.java @@ -0,0 +1,220 @@ +/* + * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/impl/entity/StrictContentLengthStrategy.java $ + * $Revision: 573949 $ + * $Date: 2007-09-08 22:46:25 -0700 (Sat, 08 Sep 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 org.apache.http.impl.entity; + +import org.apache.http.Header; +import org.apache.http.HttpException; +import org.apache.http.HttpMessage; +import org.apache.http.HttpVersion; +import org.apache.http.ProtocolException; +import org.apache.http.entity.ContentLengthStrategy; +import org.apache.http.protocol.HTTP; + +/** + * The strict implementation of the content length strategy. + * <p> + * This entity generator comforms to the entity transfer rules outlined in the + * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec4.4">Section 4.4</a>, + * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.6">Section 3.6</a>, + * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.41">Section 14.41</a> + * and <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec14.13">Section 14.13</a> + * of <a href="http://www.w3.org/Protocols/rfc2616/rfc2616.txt">RFC 2616</a> + * </p> + * <h>4.4 Message Length</h> + * <p> + * The transfer-length of a message is the length of the message-body as it appears in the + * message; that is, after any transfer-codings have been applied. When a message-body is + * included with a message, the transfer-length of that body is determined by one of the + * following (in order of precedence): + * </p> + * <p> + * 1.Any response message which "MUST NOT" include a message-body (such as the 1xx, 204, + * and 304 responses and any response to a HEAD request) is always terminated by the first + * empty line after the header fields, regardless of the entity-header fields present in the + * message. + * </p> + * <p> + * 2.If a Transfer-Encoding header field (section 14.41) is present and has any value other + * than "identity", then the transfer-length is defined by use of the "chunked" transfer- + * coding (section 3.6), unless the message is terminated by closing the connection. + * </p> + * <p> + * 3.If a Content-Length header field (section 14.13) is present, its decimal value in + * OCTETs represents both the entity-length and the transfer-length. The Content-Length + * header field MUST NOT be sent if these two lengths are different (i.e., if a + * Transfer-Encoding + * </p> + * <pre> + * header field is present). If a message is received with both a + * Transfer-Encoding header field and a Content-Length header field, + * the latter MUST be ignored. + * </pre> + * <p> + * 4.If the message uses the media type "multipart/byteranges", and the ransfer-length is not + * otherwise specified, then this self- elimiting media type defines the transfer-length. + * This media type UST NOT be used unless the sender knows that the recipient can arse it; the + * presence in a request of a Range header with ultiple byte- range specifiers from a 1.1 + * client implies that the lient can parse multipart/byteranges responses. + * </p> + * <pre> + * A range header might be forwarded by a 1.0 proxy that does not + * understand multipart/byteranges; in this case the server MUST + * delimit the message using methods defined in items 1,3 or 5 of + * this section. + * </pre> + * <p> + * 5.By the server closing the connection. (Closing the connection cannot be used to indicate + * the end of a request body, since that would leave no possibility for the server to send back + * a response.) + * </p> + * <p> + * For compatibility with HTTP/1.0 applications, HTTP/1.1 requests containing a message-body + * MUST include a valid Content-Length header field unless the server is known to be HTTP/1.1 + * compliant. If a request contains a message-body and a Content-Length is not given, the + * server SHOULD respond with 400 (bad request) if it cannot determine the length of the + * message, or with 411 (length required) if it wishes to insist on receiving a valid + * Content-Length. + * </p> + * <p>All HTTP/1.1 applications that receive entities MUST accept the "chunked" transfer-coding + * (section 3.6), thus allowing this mechanism to be used for messages when the message + * length cannot be determined in advance. + * </p> + * <h>3.6 Transfer Codings</h> + * <p> + * Transfer-coding values are used to indicate an encoding transformation that + * has been, can be, or may need to be applied to an entity-body in order to ensure + * "safe transport" through the network. This differs from a content coding in that + * the transfer-coding is a property of the message, not of the original entity. + * </p> + * <pre> + * transfer-coding = "chunked" | transfer-extension + * transfer-extension = token *( ";" parameter ) + * </pre> + * <p> + * Parameters are in the form of attribute/value pairs. + * </p> + * <pre> + * parameter = attribute "=" value + * attribute = token + * value = token | quoted-string + * </pre> + * <p> + * All transfer-coding values are case-insensitive. HTTP/1.1 uses transfer-coding values in + * the TE header field (section 14.39) and in the Transfer-Encoding header field (section 14.41). + * </p> + * <p> + * Whenever a transfer-coding is applied to a message-body, the set of transfer-codings MUST + * include "chunked", unless the message is terminated by closing the connection. When the + * "chunked" transfer-coding is used, it MUST be the last transfer-coding applied to the + * message-body. The "chunked" transfer-coding MUST NOT be applied more than once to a + * message-body. These rules allow the recipient to determine the transfer-length of the + * message (section 4.4). + * </p> + * <h>14.41 Transfer-Encoding</h> + * <p> + * The Transfer-Encoding general-header field indicates what (if any) type of transformation has + * been applied to the message body in order to safely transfer it between the sender and the + * recipient. This differs from the content-coding in that the transfer-coding is a property of + * the message, not of the entity. + * </p> + * <pre> + * Transfer-Encoding = "Transfer-Encoding" ":" 1#transfer-coding + * </pre> + * <p> + * If multiple encodings have been applied to an entity, the transfer- codings MUST be listed in + * the order in which they were applied. Additional information about the encoding parameters + * MAY be provided by other entity-header fields not defined by this specification. + * </p> + * <h>14.13 Content-Length</h> + * <p> + * The Content-Length entity-header field indicates the size of the entity-body, in decimal + * number of OCTETs, sent to the recipient or, in the case of the HEAD method, the size of + * the entity-body that would have been sent had the request been a GET. + * </p> + * <pre> + * Content-Length = "Content-Length" ":" 1*DIGIT + * </pre> + * <p> + * Applications SHOULD use this field to indicate the transfer-length of the message-body, + * unless this is prohibited by the rules in section 4.4. + * </p> + * + * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a> + * + * @version $Revision: 573949 $ + * + * @since 4.0 + */ +public class StrictContentLengthStrategy implements ContentLengthStrategy { + + public StrictContentLengthStrategy() { + super(); + } + + public long determineLength(final HttpMessage message) throws HttpException { + if (message == null) { + throw new IllegalArgumentException("HTTP message may not be null"); + } + // Although Transfer-Encoding is specified as a list, in practice + // it is either missing or has the single value "chunked". So we + // treat it as a single-valued header here. + Header transferEncodingHeader = message.getFirstHeader(HTTP.TRANSFER_ENCODING); + Header contentLengthHeader = message.getFirstHeader(HTTP.CONTENT_LEN); + if (transferEncodingHeader != null) { + String s = transferEncodingHeader.getValue(); + if (HTTP.CHUNK_CODING.equalsIgnoreCase(s)) { + if (message.getProtocolVersion().lessEquals(HttpVersion.HTTP_1_0)) { + throw new ProtocolException( + "Chunked transfer encoding not allowed for " + + message.getProtocolVersion()); + } + return CHUNKED; + } else if (HTTP.IDENTITY_CODING.equalsIgnoreCase(s)) { + return IDENTITY; + } else { + throw new ProtocolException( + "Unsupported transfer encoding: " + s); + } + } else if (contentLengthHeader != null) { + String s = contentLengthHeader.getValue(); + try { + long len = Long.parseLong(s); + return len; + } catch (NumberFormatException e) { + throw new ProtocolException("Invalid content length: " + s); + } + } else { + return IDENTITY; + } + } + +} |