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.protocol;
29
30 import java.util.Map;
31 import java.util.concurrent.ConcurrentHashMap;
32
33 import org.apache.http.annotation.ThreadingBehavior;
34 import org.apache.http.annotation.Contract;
35 import org.apache.http.util.Args;
36
37 /**
38 * Default implementation of {@link HttpContext}.
39 * <p>
40 * Please note instances of this class can be thread unsafe if the
41 * parent context is not thread safe.
42 *
43 * @since 4.0
44 */
45 @Contract(threading = ThreadingBehavior.SAFE_CONDITIONAL)
46 public class BasicHttpContext implements HttpContext {
47
48 private final HttpContext parentContext;
49 private final Map<String, Object> map;
50
51 public BasicHttpContext() {
52 this(null);
53 }
54
55 public BasicHttpContext(final HttpContext parentContext) {
56 super();
57 this.map = new ConcurrentHashMap<String, Object>();
58 this.parentContext = parentContext;
59 }
60
61 @Override
62 public Object getAttribute(final String id) {
63 Args.notNull(id, "Id");
64 Object obj = this.map.get(id);
65 if (obj == null && this.parentContext != null) {
66 obj = this.parentContext.getAttribute(id);
67 }
68 return obj;
69 }
70
71 @Override
72 public void setAttribute(final String id, final Object obj) {
73 Args.notNull(id, "Id");
74 if (obj != null) {
75 this.map.put(id, obj);
76 } else {
77 this.map.remove(id);
78 }
79 }
80
81 @Override
82 public Object removeAttribute(final String id) {
83 Args.notNull(id, "Id");
84 return this.map.remove(id);
85 }
86
87 /**
88 * @since 4.2
89 */
90 public void clear() {
91 this.map.clear();
92 }
93
94 @Override
95 public String toString() {
96 return this.map.toString();
97 }
98
99 }