loadonstartupinterceptor.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

/*
 * ====================================================================
 *
 * 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
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 *
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 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * [Additional notices, if required by prior licensing conditions]
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 */ 


package org.apache.tomcat.context;

import org.apache.tomcat.core.*;
import org.apache.tomcat.core.Constants;
import org.apache.tomcat.util.*;
import java.io.*;
import java.net.*;
import java.util.*;

/**
 * Interceptor that loads the "load-on-startup" servlets
 *
 * @author [e-mail]
 */
public class LoadOnStartupInterceptor extends BaseInterceptor {
    private static StringManager sm =
	StringManager.getManager("org.apache.tomcat.resources");
    
    public LoadOnStartupInterceptor() {
    }

    public void contextInit(Context ctx) {
	Hashtable loadableServlets = new Hashtable();
	init(ctx,loadableServlets);
	
	Vector orderedKeys = new Vector();
	Enumeration e=  loadableServlets.keys();
		
	// order keys
	while (e.hasMoreElements()) {
	    Integer key = (Integer)e.nextElement();
	    int slot = -1;
	    for (int i = 0; i < orderedKeys.size(); i++) {
	        if (key.intValue() <
		    ((Integer)(orderedKeys.elementAt(i))).intValue()) {
		    slot = i;
		    break;
		}
	    }
	    if (slot > -1) {
	        orderedKeys.insertElementAt(key, slot);
	    } else {
	        orderedKeys.addElement(key);
	    }
	}

	// loaded ordered servlets

	// Priorities IMO, should start with 0.
	// Only System Servlets should be at 0 and rest of the
	// servlets should be +ve integers.
	// WARNING: Please do not change this without talking to:
	// [e-mail] (J2EE impact)

	for (int i = 0; i < orderedKeys.size(); i ++) {
	    Integer key = (Integer)orderedKeys.elementAt(i);
	    Enumeration sOnLevel =  ((Vector)loadableServlets.get( key )).elements();
	    while (sOnLevel.hasMoreElements()) {
		String servletName = (String)sOnLevel.nextElement();
		ServletWrapper  result = ctx.getServletByName(servletName);

		if( ctx.getDebug() > 0 ) ctx.log("Loading " + key + " "  + servletName );
		if(result==null)
		    System.out.println("Warning: we try to load an undefined servlet " + servletName);
		else {
		    try {
			if( result.getPath() != null )
			    loadJsp( ctx, result );
			else {
			    result.init();
			}
		    } catch (Exception ee) {
			String msg = sm.getString("context.loadServlet.e",
						  servletName);
			System.out.println(msg+": "+ee.getMessage());
		    } 
		}
	    }
	}
    }

    void loadJsp( Context context, ServletWrapper result ) throws Exception {
	// A Jsp initialized in web.xml -

	// Log ( since I never saw this code called, let me know if it does
	// for you )
	System.out.println("Initializing JSP with JspWrapper");
	
	// Ugly code to trick JSPServlet into loading this.
	ContextManager cm=context.getContextManager();
	String path=result.getPath();
	RequestImpl request = new RequestImpl();
	ResponseImpl response = new ResponseImpl();
	request.setContextManager( cm );
	request.recycle();
	response.recycle();
	
	request.setResponse(response);
	response.setRequest(request);
	
	String requestURI = path + "?jsp_precompile=true";
	
	request.setRequestURI(context.getPath() + path);
	request.setQueryString( "jsp_precompile=true" );
	
	request.setContext(context);
//	request.getSession(true);

	cm.service( request, response );
// 	    RequestDispatcher rd = context.getFacade().getRequestDispatcher(requestURI);
	
// 	    rd.forward(request.getFacade(), response.getFacade());
// 	} catch (IOException ioe) {
// 	}
    }
    // -------------------- 
    // Old logic from Context - probably something cleaner can replace it.

    void init(Context ctx, Hashtable loadableServlets ) {
	Enumeration enum=ctx.getServletNames();
	while(enum.hasMoreElements()) {
	    String name=(String)enum.nextElement();
	    ServletWrapper sw=ctx.getServletByName( name );
	    if(sw.getLoadOnStartUp()) {
	    Integer level=new Integer(sw.getLoadOnStartUpLevel());
		Vector v;
		if( loadableServlets.get(level) != null ) 
		    v=(Vector)loadableServlets.get(level);
		else
		    v=new Vector();
		
		v.addElement(name);
		loadableServlets.put(level, v);
	    }
	}
    }
    

}