de.highbyte_le.weberknecht.request.view.WebActionProcessor.java Source code

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Here is the source code for de.highbyte_le.weberknecht.request.view.WebActionProcessor.java

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/*
 * WebActionProcessor.java (weberknecht)
 *
 * Copyright 2010-2012 Patrick Mairif.
 * The program is distributed under the terms of the Apache License (ALv2).
 * 
 * tabstop=4, charset=UTF-8
 */
package de.highbyte_le.weberknecht.request.view;

import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import de.highbyte_le.weberknecht.request.ContentProcessingException;
import de.highbyte_le.weberknecht.request.Executable;
import de.highbyte_le.weberknecht.request.ModelHelper;
import de.highbyte_le.weberknecht.request.View;

/**
 * Process usual web actions
 * 
 * @author pmairif
 */
public class WebActionProcessor implements ActionViewProcessor {

    private final Log log = LogFactory.getLog(WebActionProcessor.class);

    private ServletContext servletContext = null;

    /* (non-Javadoc)
     * @see de.highbyte_le.weberknecht.request.ActionProcessor#processAction(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, de.highbyte_le.weberknecht.request.ExecutableAction)
     */
    @Override
    public boolean processView(HttpServletRequest request, HttpServletResponse response, Executable action)
            throws ServletException, IOException, ContentProcessingException {

        if (action instanceof WebView)
            return processView(request, response, (WebView) action);

        throw new IllegalArgumentException("Action not applicable here.");
    }

    public boolean processView(HttpServletRequest request, HttpServletResponse response, WebView action)
            throws ServletException, IOException, ContentProcessingException {
        if (log.isDebugEnabled())
            log.debug("processView() - processing action " + action.getClass().getSimpleName());

        boolean processed = false;
        View view = action.getView();
        if (view != null && view.hasJspFileName()) {
            processJsp(request, response, view, action.getModels(), action); //(Don't fetch model on redirect!!)
            processed = true;
        } else if (view != null && view.hasRedirection()) {
            //TODO throw RedirectException instead
            processRedirect(response, view);
            processed = true;
        } else {
            log.warn("processView() - " + action.getClass().getName() + " produced no view and no redirection");
        }

        return processed;
    }

    protected void processJsp(HttpServletRequest request, HttpServletResponse response, View view,
            Map<String, Object> modelMap, Object action) throws ServletException, IOException {
        if (log.isDebugEnabled())
            log.debug("processJsp() - forward the request to the given view: " + view.getJspFileName());

        //add models to request
        if (modelMap != null) {
            ModelHelper modelHelper = new ModelHelper(request, servletContext);
            for (Entry<String, Object> e : modelMap.entrySet()) {
                modelHelper.set(e.getKey(), e.getValue());
            }
        }

        //forward the request to the given view
        RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/jsp/" + view.getJspFileName());
        dispatcher.forward(request, response);
    }

    protected void processRedirect(HttpServletResponse response, View view) {
        if (log.isDebugEnabled())
            log.debug("processRedirect() - initiate redirection to: " + view.getRedirection());

        response.setHeader("Location", view.getRedirection().toExternalForm());
        response.setStatus(303); //303 - "see other" (http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html)
    }

    /* (non-Javadoc)
     * @see de.highbyte_le.weberknecht.request.ActionViewProcessor#setServletContext(javax.servlet.ServletContext)
     */
    @Override
    public void setServletContext(ServletContext servletContext) {
        this.servletContext = servletContext;
    }

    @Override
    public void setActionViewProcessorFactory(ActionViewProcessorFactory factory) {
        //
    }
}