jakarta.servlet.jsp.JspPage 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.jsp;
import jakarta.servlet.Servlet;
/**
* The JspPage interface describes the generic interaction that a JSP Page Implementation class must satisfy; pages that
* use the HTTP protocol are described by the HttpJspPage interface.
*
*
* Two plus One Methods
*
* The interface defines a protocol with 3 methods; only two of them: jspInit() and jspDestroy() are part of this
* interface as the signature of the third method: _jspService() depends on the specific protocol used and cannot be
* expressed in a generic way in Java.
*
* A class implementing this interface is responsible for invoking the above methods at the appropriate time based on
* the corresponding Servlet-based method invocations.
*
* The jspInit() and jspDestroy() methods can be defined by a JSP author, but the _jspService() method is defined
* automatically by the JSP processor based on the contents of the JSP page.
*
*
* _jspService()
*
* The _jspService()method corresponds to the body of the JSP page. This method is defined automatically by the JSP
* container and should never be defined by the JSP page author.
*
* If a superclass is specified using the extends attribute, that superclass may choose to perform some actions in its
* service() method before or after calling the _jspService() method. See using the extends attribute in the JSP_Engine
* chapter of the JSP specification.
*
* The specific signature depends on the protocol supported by the JSP page.
*
*
* public void _jspService(ServletRequestSubtype request,
* ServletResponseSubtype response)
* throws ServletException, IOException;
*
*/
public interface JspPage extends Servlet {
/**
* The jspInit() method is invoked when the JSP page is initialized. It is the responsibility of the JSP
* implementation (and of the class mentioned by the extends attribute, if present) that at this point invocations
* to the getServletConfig() method will return the desired value.
*
* A JSP page can override this method by including a definition for it in a declaration element.
*
* A JSP page should redefine the init() method from Servlet.
*/
public void jspInit();
/**
* The jspDestroy() method is invoked when the JSP page is about to be destroyed.
*
* A JSP page can override this method by including a definition for it in a declaration element.
*
* A JSP page should redefine the destroy() method from Servlet.
*/
public void jspDestroy();
}