/*
 * Copyright 2000-2004 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.webapp.example;

import java.util.ArrayList;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.webapp.example.UserDatabase;
import org.apache.struts.util.MessageResources;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionForward;


/**
 * <p>
 * Confirm required resources are available. If a resource is missing,
 * forward to "failure". Otherwise, forward to "success", where
 * success is usually the "welcome" page.
 * </p>
 * <p>
 * Since "required resources" includes the application MessageResources
 * the failure page must not use the standard error or message tags.
 * Instead, it display the Strings stored in an ArrayList stored under
 * the request attribute "ERROR".
 * </p>
 *
 * @version $Revision: 1.1 $ $Date: 2004/07/29 22:23:03 $
 */
public final class WelcomeAction extends BaseAction {

    // --------------------------------------------------------- Public Methods

         // See superclass for Javadoc
    public ActionForward execute(
        ActionMapping mapping,
        ActionForm form,
        HttpServletRequest request,
        HttpServletResponse response)
        throws Exception {

        // Setup message array in case there are errors
        ArrayList messages = new ArrayList();

        // Confirm message resources loaded
        MessageResources resources = getResources(request);
        if (resources==null) {
            messages.add(Constants.ERROR_MESSAGES_NOT_LOADED);
        }

        // Confirm database loaded
        UserDatabase userDatabase = getUserDatabase(request);
        if (userDatabase==null) {
            messages.add(Constants.ERROR_DATABASE_NOT_LOADED);
        }

        // If there were errors, forward to our failure page
        if (messages.size()>0) {
            request.setAttribute(Constants.ERROR_KEY,messages);
            return findFailure(mapping);
        }

        // Forward to our success page
        return findSuccess(mapping);

    }

}
