javax.servlet.jsp.JspFactory Maven / Gradle / Ivy
/*
* 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.jsp;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
/**
*
* The JspFactory is an abstract class that defines a number of factory
* methods available to a JSP page at runtime for the purposes of creating
* instances of various interfaces and classes used to support the JSP
* implementation.
*
* A conformant JSP Engine implementation will, during it's initialization
* instantiate an implementation dependent subclass of this class, and make
* it globally available for use by JSP implementation classes by registering
* the instance created with this class via the
* static setDefaultFactory() method.
*
* The PageContext and the JspEngineInfo classes are the only
* implementation-dependent classes that can be created from the factory.
*
* JspFactory objects should not be used by JSP page authors.
*/
public abstract class JspFactory {
private static volatile JspFactory deflt = null;
/**
* Sole constructor. (For invocation by subclass constructors,
* typically implicit.)
*/
public JspFactory() {
// NOOP by default
}
/**
*
* set the default factory for this implementation. It is illegal for
* any principal other than the JSP Engine runtime to call this method.
*
*
* @param deflt The default factory implementation
*/
public static void setDefaultFactory(JspFactory deflt) {
JspFactory.deflt = deflt;
}
/**
* Returns the default factory for this implementation.
*
* @return the default factory for this implementation
*/
public static JspFactory getDefaultFactory() {
return deflt;
}
/**
*
* obtains an instance of an implementation dependent
* javax.servlet.jsp.PageContext abstract class for the calling Servlet
* and currently pending request and response.
*
*
*
* This method is typically called early in the processing of the
* _jspService() method of a JSP implementation class in order to
* obtain a PageContext object for the request being processed.
*
*
* Invoking this method shall result in the PageContext.initialize()
* method being invoked. The PageContext returned is properly initialized.
*
*
* All PageContext objects obtained via this method shall be released
* by invoking releasePageContext().
*
*
* @param servlet the requesting servlet
* @param request the current request pending on the servlet
* @param response the current response pending on the servlet
* @param errorPageURL the URL of the error page for the requesting JSP, or
* null
* @param needsSession true if the JSP participates in a session
* @param buffer size of buffer in bytes, PageContext.NO_BUFFER if no
* buffer, PageContext.DEFAULT_BUFFER if
* implementation default.
* @param autoflush should the buffer autoflush to the output stream on
* buffer overflow, or throw an IOException?
*
* @return the page context
*
* @see javax.servlet.jsp.PageContext
*/
public abstract PageContext getPageContext(Servlet servlet,
ServletRequest request, ServletResponse response,
String errorPageURL, boolean needsSession, int buffer,
boolean autoflush);
/**
*
* called to release a previously allocated PageContext object.
* Results in PageContext.release() being invoked.
* This method should be invoked prior to returning from the _jspService()
* method of a JSP implementation class.
*
*
* @param pc A PageContext previously obtained by getPageContext()
*/
public abstract void releasePageContext(PageContext pc);
/**
*
* called to get implementation-specific information on the current JSP
* engine.
*
*
* @return a JspEngineInfo object describing the current JSP engine
*/
public abstract JspEngineInfo getEngineInfo();
/**
*
* Obtain the JspApplicationContext instance that was
* associated within the passed ServletContext for this web
* application.
*
*
* @param context the current web application's ServletContext
* @return JspApplicationContext instance
* @since 2.1
*/
public abstract JspApplicationContext getJspApplicationContext(
ServletContext context);
}