confighelper.java

jakarta-struts-1.2.4-src

/*
 * $Header: /home/cvs/jakarta-struts/src/share/org/apache/struts/config/ConfigHelper.java,v 1.17 2004/03/14 06:23:47 sraeburn Exp $
 * $Revision: 1.17 $
 * $Date: 2004/03/14 06:23:47 $
 *
 * Copyright 1999-2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.struts.config;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;

import org.apache.struts.Globals;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionFormBean;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessages;
import org.apache.struts.upload.MultipartRequestWrapper;
import org.apache.struts.util.MessageResources;
import org.apache.struts.util.RequestUtils;

/**
 * NOTE: THIS CLASS IS UNDER ACTIVE DEVELOPMENT.
 * THE CURRENT CODE IS WRITTEN FOR CLARITY NOT EFFICIENCY.
 * NOT EVERY API FUNCTION HAS BEEN IMPLEMENTED YET.
 *
 * A helper object to expose the Struts shared resources,
 * which are be stored in the application, session, or
 * request contexts, as appropriate.
 *
 * An instance should be created for each request
 * processed. The  methods which return resources from
 * the request or session contexts are not thread-safe.
 *
 * Provided for use by other servlets in the application
 * so they can easily access the Struts shared resources.
 *
 * The resources are stored under attributes in the
 * application, session, or request contexts.
 *
 * The ActionConfig methods simply return the resources
 * from under the context and key used by the Struts
 * ActionServlet when the resources are created.
 *
 * @since Struts 1.1
 * @version $Revision: 1.17 $ $Date: 2004/03/14 06:23:47 $
 */
public class ConfigHelper implements ConfigHelperInterface {

    // --------------------------------------------------------  Properites

    /**
     * The application associated with this instance.
     */
    private ServletContext application = null;

    /**
     * Set the application associated with this instance.
     * [servlet.getServletContext()]
     */
    public void setApplication(ServletContext application) {
        this.application = application;
    }

    /**
     * The session associated with this instance.
     */
    private HttpSession session = null;

    /**
     * Set the session associated with this instance.
     */
    public void setSession(HttpSession session) {
        this.session = session;
    }

    /**
     * The request associated with this instance.
     */
    private HttpServletRequest request = null;

    /**
     * Set the request associated with this object.
     * Session object is also set or cleared.
     */
    public void setRequest(HttpServletRequest request) {
        this.request = request;
        if (this.request == null)
            setSession(null);
        else
            setSession(this.request.getSession());
    }

    /**
     * The response associated with this instance.
     */
    private HttpServletResponse response = null;

    /**
     * Set the response associated with this isntance.
     * Session object is also set or cleared.
     */
    public void setResponse(HttpServletResponse response) {
        this.response = response;
    }

    /**
     * The forward associated with this instance.
     */
    private ActionForward forward = null;

    /**
     * Set the forward associated with this instance.
     */
    public void setForward(ActionForward forward) {
        this.forward = forward;
    }

    /**
     * Set the application and request for this object instance.
     * The ServletContext can be set by any servlet in the application.
     * The request should be the instant request.
     * Most of the other methods retrieve their own objects
     * by reference to the application, request, or session
     * attributes.
     * Do not call other methods without setting these first!
     * This is also called by the convenience constructor.
     *
     * @param application - The associated ServletContext.
     * @param request - The associated HTTP request.
     * @param response - The associated HTTP response.
     */
    public void setResources(
        ServletContext application,
        HttpServletRequest request,
        HttpServletResponse response) {
        
        setApplication(application);
        setRequest(request);
        setResponse(response);
    }
    
    public ConfigHelper() {
        super();
    }

    public ConfigHelper(
        ServletContext application,
        HttpServletRequest request,
        HttpServletResponse response) {
            
        super();
        this.setResources(application, request, response);
    }
    

    // ------------------------------------------------ Application Context

    /**
     * The <strong>default</strong>
     * configured data source (which must implement
     * <code>javax.sql.DataSource</code>),
     * if one is configured for this application.
     */
    public DataSource getDataSource() {

        if (this.application == null)
            return null;
        return (DataSource) this.application.getAttribute(Globals.DATA_SOURCE_KEY);

    }

    public ActionMessages getActionMessages() {

        if (this.application == null)
            return null;
        return (ActionMessages) this.application.getAttribute(Globals.MESSAGE_KEY);

    }

    /**
     * The application resources for this application.
     */
    public MessageResources getMessageResources() {

        if (this.application == null) {
            return null;
        }
        return (MessageResources) this.application.getAttribute(Globals.MESSAGES_KEY);

    }

    /**
     * The path-mapped pattern (<code>/action/*</code>) or
     * extension mapped pattern ((<code>*.do</code>)
     * used to determine our Action URIs in this application.
     */
    public String getServletMapping() {

        if (this.application == null) {
            return null;
        }
        return (String) this.application.getAttribute(Globals.SERVLET_KEY);

    }

    // ---------------------------------------------------- Session Context

    /**
     * The transaction token stored in this session, if it is used.
     */
    public String getToken() {

        if (this.session == null) {
            return null;
        }
        return (String) session.getAttribute(Globals.TRANSACTION_TOKEN_KEY);

    }

    // ---------------------------------------------------- Request Context

    /**
     * The runtime JspException that may be been thrown by a Struts tag
     * extension, or compatible presentation extension, and placed
     * in the request.
     */
    public Throwable getException() {

        if (this.request == null) {
            return null;
        }
        return (Throwable) this.request.getAttribute(Globals.EXCEPTION_KEY);

    }

    /**
     * The multipart object for this request.
     */
    public MultipartRequestWrapper getMultipartRequestWrapper() {

        if (this.request == null) {
            return null;
        }
        return (MultipartRequestWrapper) this.request.getAttribute(Globals.MULTIPART_KEY);
    }

    /**
      * The <code>org.apache.struts.ActionMapping</code>
      * instance for this request.
      */
    public ActionMapping getMapping() {

        if (this.request == null) {
            return null;
        }
        return (ActionMapping) this.request.getAttribute(Globals.MAPPING_KEY);

    }

    // ---------------------------------------------------- Utility Methods

    /**
     * Return true if a message string for the specified message key
     * is present for the user's Locale.
     *
     * @param key Message key
     */
    public boolean isMessage(String key) {

        // Look up the requested MessageResources
        MessageResources resources = getMessageResources();

        if (resources == null) {
            return false;
        }

        // Return the requested message presence indicator
        return resources.isPresent(RequestUtils.getUserLocale(request, null), key);

    }

    /*