package com.sun.j2ee.workflow.control.web;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpSession;import javax.servlet.ServletContext;import java.util.HashMap;import java.util.Iterator;import java.util.Locale;import com.sun.j2ee.workflow.util.JSPUtil;import com.sun.j2ee.workflow.util.WebKeys;import com.sun.j2ee.workflow.control.actions.FlowHandler;import com.sun.j2ee.workflow.util.Debug;/** This file looks at the Request URL and maps the request * to the page for the web-templating mechanism. * @author Jian (James) Cai */public class ScreenFlowManager implements java.io.Serializable {    private HashMap screens;    private HashMap urlMappings;    private HashMap exceptionMappings;    private HashMap screenDefinitionMappings;    private String defaultScreen = "MAIN";    private String signinScreen = "SIGN_IN";    private String signinErrorScreen = "SIGN_IN_ERROR";    public ScreenFlowManager() {        screens = new HashMap();    }    public void init(ServletContext context) {        String screenDefinitionsURL = null;        String requestMappingsURL = null;        try {            requestMappingsURL = context.getResource("/WEB-INF/xml/requestmappings.xml").toString();        } catch (java.net.MalformedURLException ex) {            Debug.println("ScreenFlowManager: initializing ScreenFlowManager malformed URL exception: " + ex);        }        ScreenFlowData screenFlowData = ScreenFlowXmlDAO.loadScreenFlowData(requestMappingsURL);        defaultScreen = screenFlowData.getDefaultScreen();        signinScreen = screenFlowData.getSigninScreen();        signinErrorScreen = screenFlowData.getSigninErrorScreen();        Debug.println("ScreenFlowManager: **** ScreenFlowData = " + screenFlowData);        Debug.println("Loading Exception mappings");        exceptionMappings = screenFlowData.getExceptionMappings();        Debug.println("Exception mappings=" + exceptionMappings);        screenDefinitionMappings = screenFlowData.getScreenDefinitionMappings();        Iterator it = screenDefinitionMappings.keySet().iterator();        while (it.hasNext()) {            String language = (String)it.next();            Debug.println("ScreenFlowManager loading screen definitions for language " + language);            try {                String mappings = (String)screenDefinitionMappings.get(language);                Debug.println("ScreenFlowManager: mappings are: " + mappings);                screenDefinitionsURL = context.getResource(mappings).toString();            } catch (java.net.MalformedURLException ex) {                Debug.println("ScreenFlowManager: initializing ScreenFlowManager malformed URL exception: " + ex);            }            HashMap screenDefinitions = ScreenFlowXmlDAO.loadScreenDefinitions(screenDefinitionsURL);            screens.put(language, screenDefinitions);        }        // looad url mappings from the context        urlMappings = (HashMap)context.getAttribute(WebKeys.URLMappingsKey);        Debug.println("ScreenFlowManager:  initialized Screens and mappings");    }    private URLMapping getURLMapping(String urlPattern) {        if ((urlMappings != null) && urlMappings.containsKey(urlPattern)) {            return (URLMapping)urlMappings.get(urlPattern);        } else {            return null;        }    }    public String getExceptionScreen(String exceptionClassName) {        return (String)exceptionMappings.get(exceptionClassName);    }    /**        Get the screens for the specified language.    */    public HashMap getScreens(Locale locale) {        String languageKey = locale.getLanguage() + "_" + locale.getCountry();        if (screens.containsKey(languageKey)) {            Debug.println("screen contains : "+ languageKey);            return (HashMap)screens.get(languageKey);        }        return null;    }    /**        Get the template for the specified language.    */    public String getTemplate(Locale locale) {                HashMap localeScreens = getScreens(locale);        if (localeScreens == null) return null;        else return (String)localeScreens.get(ScreenFlowXmlDAO.TEMPLATE);                // return "/jsp/template.jsp";            }    public void getNextScreen(HttpServletRequest request) {        // set the presious screen        String previousScreen = (String)request.getSession().getAttribute(WebKeys.CurrentScreen);        if (previousScreen != null) request.getSession().setAttribute(WebKeys.PreviousScreen, previousScreen);        String selectedURL = request.getPathInfo();        String currentScreen = defaultScreen;        URLMapping urlMapping = getURLMapping(selectedURL);        if (urlMapping != null) {            if (!urlMapping.useFlowHandler()) {                currentScreen = urlMapping.getScreen();            } else {                Debug.println("ScreenFlowManager: using flow handler for:" + selectedURL);                // load the flow handler                FlowHandler handler = null;                String flowHandlerString = urlMapping.getFlowHandler();                try {                    handler = (FlowHandler)getClass().getClassLoader().loadClass(flowHandlerString).newInstance();                    // invoke the processFlow(HttpServletRequest)                    handler.doStart(request);                    String flowResult = handler.processFlow(request);                    Debug.println("ScreenFlowManager: flow handler processing result=" + flowResult);                    handler.doEnd(request);                    // get the matching screen from the URLMapping object                    if (flowResult.equals("TARGET_URL")) {                        String urlPattern = (String)request.getSession().getAttribute(WebKeys.SigninTargetURL);                        currentScreen = getURLMapping(urlPattern).getScreen();                        Debug.println("ScreenFlowManager: using SigninTargetURL=" + currentScreen);                    } else {                        currentScreen = urlMapping.getResultScreen(flowResult);                         Debug.println("ScreenFlowManager: using =" + currentScreen);                    }               } catch (Exception ex) {                   Debug.println("ScreenFlowManager caught loading handler: " + ex);               }            }        }        if (currentScreen != null) {            request.getSession().setAttribute(WebKeys.CurrentScreen, currentScreen);        } else {            Debug.println("ScreenFlowManager: Screen not found for " + selectedURL);            throw new RuntimeException("Screen not found for " + selectedURL);        }    }    public void setDefaultScreen(String defaultScreen) {        this.defaultScreen = defaultScreen;    }    public Parameter getParameter(String key, HttpSession session) {        String currentScreen = (String)session.getAttribute(WebKeys.CurrentScreen);        Locale locale = JSPUtil.getLocale(session);        if (currentScreen == null) currentScreen = defaultScreen;        if (screens == null || currentScreen == null) return null;        Screen screen = (Screen)getScreens(locale).get(currentScreen);        if (screen == null) {            return null;        }        Debug.println("ScreenFlowManager: getParameter: " + key);        return screen.getParameter(key);    }    /**     * Returs the current screen     */    public String getCurrentScreen(HttpSession session)  {        return (String)session.getAttribute(WebKeys.CurrentScreen);    }    public String getSigninScreen() {        return signinScreen;    }}