001// Copyright 2004, 2005 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.hivemind.service; 016 017/** 018 * Provides a service which can temporarily store 019 * thread-local data. This is useful in a multithreaded 020 * environment, such as a servlet or Tapestry application. 021 * ThreadLocalStorage acts like a map around thread local data. 022 * 023 * @author Howard Lewis Ship 024 */ 025public interface ThreadLocalStorage 026{ 027 /** 028 * Returns the thread-local object for the given key, or null 029 * if no such object exists. 030 */ 031 public Object get(String key); 032 033 /** 034 * Stores the value object at the given key, overwriting 035 * any prior value that may have been stored at that key. 036 * Care should be taken in selecting keys to avoid 037 * naming conflicts; in general, prefixing a key with 038 * a module id is a good idea. 039 */ 040 public void put(String key, Object value); 041 042 /** 043 * Clears all keys. 044 */ 045 public void clear(); 046}