1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.impl.entity;
29
30 import org.apache.http.Header;
31 import org.apache.http.HttpException;
32 import org.apache.http.HttpMessage;
33 import org.apache.http.HttpVersion;
34 import org.apache.http.ProtocolException;
35 import org.apache.http.annotation.ThreadingBehavior;
36 import org.apache.http.annotation.Contract;
37 import org.apache.http.entity.ContentLengthStrategy;
38 import org.apache.http.protocol.HTTP;
39 import org.apache.http.util.Args;
40
41 /**
42 * The strict implementation of the content length strategy. This class
43 * will throw {@link ProtocolException} if it encounters an unsupported
44 * transfer encoding or a malformed {@code Content-Length} header
45 * value.
46 * <p>
47 * This class recognizes "chunked" and "identitiy" transfer-coding only.
48 *
49 * @since 4.0
50 */
51 @Contract(threading = ThreadingBehavior.IMMUTABLE)
52 public class StrictContentLengthStrategy implements ContentLengthStrategy {
53
54 public static final StrictContentLengthStrategy INSTANCE = new StrictContentLengthStrategy();
55
56 private final int implicitLen;
57
58 /**
59 * Creates {@code StrictContentLengthStrategy} instance with the given length used per default
60 * when content length is not explicitly specified in the message.
61 *
62 * @param implicitLen implicit content length.
63 *
64 * @since 4.2
65 */
66 public StrictContentLengthStrategy(final int implicitLen) {
67 super();
68 this.implicitLen = implicitLen;
69 }
70
71 /**
72 * Creates {@code StrictContentLengthStrategy} instance. {@link ContentLengthStrategy#IDENTITY}
73 * is used per default when content length is not explicitly specified in the message.
74 */
75 public StrictContentLengthStrategy() {
76 this(IDENTITY);
77 }
78
79 @Override
80 public long determineLength(final HttpMessage message) throws HttpException {
81 Args.notNull(message, "HTTP message");
82 // Although Transfer-Encoding is specified as a list, in practice
83 // it is either missing or has the single value "chunked". So we
84 // treat it as a single-valued header here.
85 final Header transferEncodingHeader = message.getFirstHeader(HTTP.TRANSFER_ENCODING);
86 if (transferEncodingHeader != null) {
87 final String s = transferEncodingHeader.getValue();
88 if (HTTP.CHUNK_CODING.equalsIgnoreCase(s)) {
89 if (message.getProtocolVersion().lessEquals(HttpVersion.HTTP_1_0)) {
90 throw new ProtocolException(
91 "Chunked transfer encoding not allowed for " +
92 message.getProtocolVersion());
93 }
94 return CHUNKED;
95 } else if (HTTP.IDENTITY_CODING.equalsIgnoreCase(s)) {
96 return IDENTITY;
97 } else {
98 throw new ProtocolException(
99 "Unsupported transfer encoding: " + s);
100 }
101 }
102 final Header contentLengthHeader = message.getFirstHeader(HTTP.CONTENT_LEN);
103 if (contentLengthHeader != null) {
104 final String s = contentLengthHeader.getValue();
105 try {
106 final long len = Long.parseLong(s);
107 if (len < 0) {
108 throw new ProtocolException("Negative content length: " + s);
109 }
110 return len;
111 } catch (final NumberFormatException e) {
112 throw new ProtocolException("Invalid content length: " + s);
113 }
114 }
115 return this.implicitLen;
116 }
117
118 }
119