001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *  http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing,
013     * software distributed under the License is distributed on an
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015     * KIND, either express or implied.  See the License for the
016     * specific language governing permissions and limitations
017     * under the License.
018     */
019    
020    //
021    // This source code implements specifications defined by the Java
022    // Community Process. In order to remain compliant with the specification
023    // DO NOT add / change / or delete method signatures!
024    //
025    
026    package javax.servlet;
027    
028    /**
029     * Ensures that servlets handle
030     * only one request at a time. This interface has no methods.
031     *
032     * <p>If a servlet implements this interface, you are <i>guaranteed</i>
033     * that no two threads will execute concurrently in the
034     * servlet's <code>service</code> method. The servlet container
035     * can make this guarantee by synchronizing access to a single
036     * instance of the servlet, or by maintaining a pool of servlet
037     * instances and dispatching each new request to a free servlet.
038     *
039     * <p>Note that SingleThreadModel does not solve all thread safety
040     * issues.  For example, session attributes and static variables can
041     * still be accessed by multiple requests on multiple threads
042     * at the same time, even when SingleThreadModel servlets are used.
043     * It is recommended that a developer take other means to resolve
044     * those issues instead of implementing this interface, such as
045     * avoiding the usage of an instance variable or synchronizing
046     * the block of the code accessing those resources.
047     * This interface is deprecated in Servlet API version 2.4.
048     *
049     * @deprecated As of Java Servlet API 2.4, with no direct
050     * replacement.
051     *
052     * @version $Rev: 467553 $ $Date: 2006-10-24 21:01:51 -0700 (Tue, 24 Oct 2006) $
053     */
054    public interface SingleThreadModel {
055    }