enginerenderer.java

java 写的一个新闻发布系统

//
//                                   ____.
//                       __/\ ______|    |__/\.     _______
//            __   .____|    |       \   |    +----+       \
//    _______|  /--|    |    |    -   \  _    |    :    -   \_________
//   \\______: :---|    :    :           |    :    |         \________>
//           |__\---\_____________:______:    :____|____:_____\
//                                      /_____|
//
//                 . . . i n   j a h i a   w e   t r u s t . . .
//

//
//  EngineRenderer
//  EV      04.12.2000
//
//  render( sourceFile, formString )
//
//

package org.jahia.engines;


import java.io.*;                       // PrintWriter
import java.util.*;                     // HashMap
import javax.servlet.*;                 // ServletException

import org.jahia.utils.*;           // JahiaConsole
import org.jahia.params.*;          // ParamBean
import org.jahia.registries.*;      // ServicesRegistry
import org.jahia.data.*;            // JahiaData
import org.jahia.exceptions.JahiaException;


public class EngineRenderer {

    public  static final String FORM_TOKEN	= "<!--ENGINE_CONTENT-->";
    private static EngineRenderer theObject = null;
    private static final String ENGINE_JSP 	= "/jsp/jahia/engines/engine.jsp";



    /***
        * constructor
        * EV    04.12.2000
        *
        */
    private EngineRenderer()
    {
        JahiaConsole.println( "EngineRenderer", "***** Starting EngineRenderer *****" );
    } // end constructor



    /***
        * getInstance
        * EV    04.12.2000
        *
        */
    public static synchronized EngineRenderer getInstance()
    {
        if (theObject == null) {
            theObject = new EngineRenderer();
        }
        return theObject;
    } // end getInstance



    /***
        * render
        * ParamBean render
        * EV    23.12.2000
        * AK    04.01.2001  remove the fileName from method arguments
        *
        */
    public void render( ParamBean jParams, HashMap engineHashMap )
    throws JahiaException
    {
        jParams.getRequest().setAttribute("org.jahia.data.JahiaParams", jParams);
        renderCore( jParams, engineHashMap );
    } // end render



    /***
        * render
        * JahiaData render
        * EV    23.12.2000
        * AK    04.01.2001  remove the fileName from method arguments
        *
        */
    public void render( JahiaData jData, HashMap engineHashMap )
    throws JahiaException
    {
        jData.params().getRequest().setAttribute("org.jahia.data.JahiaData", jData);
        renderCore( jData.params(), engineHashMap );
    } // end render



    /***
        * renderCore
        * called by ParamBean render, JahiaData render
        * EV    23.12.2000
        * AK    04.01.2001  get the fileName from the engineHashMap and not from method arguments
        * AK    04.01.2001  get the render type from the engineHashMap (include or forward)
        * AK    04.01.2001  correct the jahiaChrono call consoleMsg
        *
        */
    private void renderCore( ParamBean jParams, HashMap engineHashMap )
    throws JahiaException
    {

        String fileName = null;
        try
        {
            // add default & common properties to the hashmap...
            engineHashMap.put("jahiaBuild",      		new Integer(jParams.settings().getBuildNumber()));
            engineHashMap.put("javaScriptPath",  		jParams.settings().getJsHttpPath());
            engineHashMap.put("imagesPath",      		jParams.settings().getEnginesContext() + "engines/images/");
            if ( engineHashMap.get("engineOutputFile") == null )
                engineHashMap.put("engineOutputFile",  		ENGINE_JSP);

            if ( engineHashMap.get("engineUrl") == null )
                engineHashMap.put("engineUrl","");


            // set response attributes...
            jParams.getResponse().setContentType("text/html");

            // add "no cache" to request header only if methode is not a get
            if (! jParams.getRequest().getMethod().toLowerCase().equals("get")){
                jParams.getResponse().setHeader("Cache-Control", "No-Cache");
                jParams.getResponse().setHeader("Pragma", "No-Cache");
                jParams.getResponse().setDateHeader("Expires", 0);
            }

            boolean isIE = false;
            String userAgent = jParams.getRequest().getHeader( "user-agent" );
            if (userAgent != null) {
                isIE = (userAgent.indexOf( "IE" ) != -1);
            }

            jParams.getRequest().setAttribute("isIE"							, new Boolean(isIE));
            jParams.getRequest().setAttribute("org.jahia.engines.EngineHashMap"	, engineHashMap);
            jParams.getRequest().setAttribute("javaScriptPath"					, jParams.settings().getJsHttpPath());
            jParams.getRequest().setAttribute("URL"								, getJahiaCoreHttpPath(jParams) + jParams.settings().getEnginesContext());
            jParams.getRequest().setAttribute("engineURL"						, getJahiaCoreHttpPath(jParams) + jParams.settings().getEnginesContext());
            jParams.getRequest().setAttribute("serverURL"						, getJahiaCoreHttpPath(jParams) );
            jParams.getRequest().setAttribute("httpJsContextPath"				, getJahiaCoreHttpPath(jParams) + jParams.settings().getJavascriptContext());

            String jspSource = (String)engineHashMap.get("jspSource");
            if ( jspSource == null )
                jspSource = "";
            jParams.getRequest().setAttribute("jspSource"						, jspSource );

            if ( jParams.getRequest().getAttribute("engineTitle")==null)
                jParams.getRequest().setAttribute("engineTitle"					, "No title");

            //jParams.getRequest().setAttribute("jParams"							, jParams);

            // get the fileName from the engineHashMap...
            fileName = (String) engineHashMap.get("engineOutputFile");

            // get the render type from the engineHashMap... (include or forward)
            Integer renderType = (Integer) engineHashMap.get("renderType");


            JahiaConsole.println("EngineRenderer.renderCore", "Dispatching request to " + fileName + " using render type " + renderType + "...");

            if(renderType.intValue() == JahiaEngine.RENDERTYPE_INCLUDE) {
                jParams.getContext().getRequestDispatcher( fileName ).include( jParams.getRequest(), jParams.getResponse() );
            } else if(renderType.intValue() == JahiaEngine.RENDERTYPE_FORWARD) {
                jParams.getContext().getRequestDispatcher( fileName ).forward( jParams.getRequest(), jParams.getResponse() );
            }
        }
        catch (IOException ie)
        {
            if (fileName == null) fileName = "undefined file";
            String errorMsg = "Error while drawing the Engine " + fileName + " : " + ie.getMessage() + " -> BAILING OUT";
            JahiaConsole.println( "Engine", errorMsg );
            throw new JahiaException(   "Error while drawing a Jahia engine's content",
                                        errorMsg, JahiaException.WINDOW_ERROR, JahiaException.CRITICAL, ie );
        }
        catch (ServletException se)
        {
            if (fileName == null) fileName = "undefined file";
            String errorMsg = "Error while forwarding the Engine " + fileName + " : " + se.getMessage() + " -> BAILING OUT";
            JahiaConsole.println( "Engine", errorMsg );
            if (se.getRootCause() != null) {
                se.getRootCause().printStackTrace(System.out);
            }
            throw new JahiaException(   "Error while forwarding a Jahia engine's content",
                                        errorMsg, JahiaException.WINDOW_ERROR, JahiaException.CRITICAL, se );
        }
    } // end renderCore



    //-------------------------------------------------------------------------
    /**
     * Build an http path containing the server name for the current site,
     * instead of the path from JahiaPrivateSettings.
     *
     * @return An http path leading to Jahia, built with the server name, and
     *         the server port if nonstandard.
     *
     */
    private final String getJahiaCoreHttpPath (ParamBean jParams)
    {
        return jParams.getRequest().getContextPath();
    }


/*******************************************************************************
****                                                                        ****
****        A PARTIR DE LA CES METHODES SONT DESTINEES A MOURIR....         ****
****                                                                        ****
*******************************************************************************/


    /***
        * render
        * EV    04.12.2000
        *
        */
    public void render( JahiaData jData, String sourceFileName, String formString )
    throws JahiaException
    {
        String fileName = jData.params().settings().getJahiaEnginesDiskPath() + File.separator + sourceFileName + ".html";
        String finalSource  = decomposeSource( fileName, formString );
        displaySource( finalSource, jData.params() );
    } // end render


    /***
        * render
        * EV    04.12.2000
        *
        */
    public void render( ParamBean jParams, String sourceFileName, String formString )
    throws JahiaException
    {
        String fileName = jParams.settings().getJahiaEnginesDiskPath() + File.separator + sourceFileName + ".html";
        String finalSource  = decomposeSource( fileName, formString );
        displaySource( finalSource, jParams );
    } // end render



    /***
        * decomposeSource
        * EV    04.12.2000
        *
        */

    private String decomposeSource( String fileName, String form )
    throws JahiaException
    {
        String source       = FileUtils.getInstance().readFile( fileName );
        String firstPart    = source.substring( 0, source.indexOf( FORM_TOKEN ) );
        String secondPart   = source.substring( source.indexOf(FORM_TOKEN) + FORM_TOKEN.length(), source.length() );
        return firstPart + form + secondPart;
    } // end decomposeSource



    /***
        * displaySource
        * EV    04.12.2000
        *
        */
    public void displaySource( String source, ParamBean jParams )
    throws JahiaException
    {
        try {
            PrintWriter out = jParams.getResponse().getWriter();
            jParams.getResponse().setContentType( "text/html" );
            out.println( source );
        } catch (IOException ie) {
            String errorMsg = "Error while drawing the Engine Window : " + ie.getMessage() + " -> BAILING OUT";
            JahiaConsole.println( "Engine", errorMsg );
            throw new JahiaException(   "Error while drawing a Jahia window's content",
                                        errorMsg, JahiaException.WINDOW_ERROR, JahiaException.CRITICAL, ie );
        }
    } // end displaySource


/*******************************************************************************
****                                                                        ****
****        JUSQU'A LA CES METHODES SONT DESTINEES A MOURIR....             ****
****                                                                        ****
*******************************************************************************/


} // end EngineRenderer