jakarta.servlet.SingleThreadModel Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2020 Oracle and/or its affiliates and others.
* 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 jakarta.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.
*
*
* @author Various
*
* @deprecated As of Java Servlet API 2.4, with no direct replacement.
*/
@Deprecated
public interface SingleThreadModel {
}