/* * 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. */ package javax.servlet; /** * Ensures that servlets handle * only one request at a time. This interface has no methods. * *
If a servlet implements this interface, you are guaranteed
* that no two threads will execute concurrently in the
* servlet's service
method. The servlet container
* can make this guarantee by synchronizing access to a single
* instance of the servlet, or by maintaining a pool of servlet
* instances and dispatching each new request to a free servlet.
*
*
Note that SingleThreadModel does not solve all thread safety * issues. For example, session attributes and static variables can * still be accessed by multiple requests on multiple threads * at the same time, even when SingleThreadModel servlets are used. * It is recommended that a developer take other means to resolve * those issues instead of implementing this interface, such as * avoiding the usage of an instance variable or synchronizing * the block of the code accessing those resources. * This interface is deprecated in Servlet API version 2.4. * * @version $Rev$ $Date$ * * @deprecated As of Java Servlet API 2.4, with no direct * replacement. */ public interface SingleThreadModel { }