Java tutorial
/* * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved. * Copyright 2004 The Apache Software Foundation * * Licensed 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. * * <p>If a servlet implements this interface, you are <i>guaranteed</i> * that no two threads will execute concurrently in the * servlet's <code>service</code> 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. * * <p>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. * * * @author Various * * @deprecated As of Java Servlet API 2.4, with no direct * replacement. */ @Deprecated public interface SingleThreadModel { }