jspfactoryimpl.java

低版本的tomcat 对于有些老版本的应用还真的需要老版的中间件

/*
 * $Header: /home/cvs/jakarta-tomcat/src/share/org/apache/jasper/runtime/JspFactoryImpl.java,v 1.4.2.2 2001/10/25 17:25:48 marcsaeg Exp $
 * $Revision: 1.4.2.2 $
 * $Date: 2001/10/25 17:25:48 $
 *
 * ====================================================================
 * 
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact [e-mail].
 *
 * 5. Products derived from this software may not be called "Apache"
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 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
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 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */ 
package org.apache.jasper.runtime;

import javax.servlet.Servlet;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import javax.servlet.jsp.JspFactory;
import javax.servlet.jsp.JspEngineInfo;
import javax.servlet.jsp.PageContext;

import org.apache.tomcat.util.SimplePool;

/**
 * Implementation of JspFactory from the spec. Helps create
 * PageContext and other animals.  
 *
 * @author Anil K. Vijendran
 */
public class JspFactoryImpl extends JspFactory {
    private SimplePool pool=new SimplePool( 100 );
    private static final boolean usePool=true;

    public PageContext getPageContext(Servlet servlet, ServletRequest request,
                                      ServletResponse response, 
				      String errorPageURL, 
                                      boolean needsSession, int bufferSize, 
                                      boolean autoflush) 
    {
        try {
	    PageContext pc;
	    if( usePool ) {
		pc=(PageContext)pool.get();
		if( pc == null ) pc= new PageContextImpl(this);
	    } else {
		pc =  new PageContextImpl(this);
	    }

	    //	    System.out.println("JspFactoryImpl.getPC"  + pc);
	    pc.initialize(servlet, request, response, errorPageURL, 
                          needsSession, bufferSize, autoflush);
	    
            return pc;
        } catch (Throwable ex) {
            /* FIXME: need to do something reasonable here!! */
            ex.printStackTrace();
            return null;
        }
    }

    public void releasePageContext(PageContext pc) {
        if(pc == null)
            return;
        pc.release();
	if( usePool) {
	    pool.put( pc );
	}
    }

    static class SunJspEngineInfo extends JspEngineInfo {
        public String getSpecificationVersion() {
            return "1.1";
        }
    }
    
    static JspEngineInfo info = new SunJspEngineInfo();

    public JspEngineInfo getEngineInfo() {
        return info;
    }
}