1 package org.apache.fulcrum.yaafi.framework.tls;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 /**
23 * Provides a service which can temporarily store
24 * thread-local data. This is useful in a multithreaded
25 * environment, such as a servlet or Tapestry application.
26 * ThreadLocalStorage acts like a map around thread local data.
27 *
28 * The code was pasted from the Hivemind container written by
29 * Howard Lewis Ship.
30 *
31 * @author <a href="mailto:siegfried.goeschl@it20one.at">Siegfried Goeschl</a>
32 */
33
34 public interface ThreadLocalStorage
35 {
36 /**
37 * Returns the thread-local object for the given key, or null
38 * if no such object exists.
39 *
40 * @param key the key for the lookup
41 * @return the object
42 */
43 public Object get(String key);
44
45 /**
46 * Stores the value object at the given key, overwriting
47 * any prior value that may have been stored at that key.
48 * Care should be taken in selecting keys to avoid
49 * naming conflicts; in general, prefixing a key with
50 * a module id is a good idea.
51 *
52 * @param key the key of the object to store
53 * @param value the value of the object to store
54 */
55 public void put(String key, Object value);
56
57 /**
58 * Checks if the thread-local object for the given key exists
59 *
60 * @param key the key for the lookup
61 * @return true the object exists
62 */
63 public boolean containsKey(String key);
64
65 /**
66 * Clears all keys.
67 */
68 public void clear();
69 }