threadprevnexlistaction.java

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/*
 * Copyright 2003-2005 the original author or authors.
 * 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 com.jdon.jivejdon.presentation.action;

import java.util.List;
import java.util.ListIterator;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

import com.jdon.controller.WebAppUtil;
import com.jdon.jivejdon.model.ForumThread;
import com.jdon.jivejdon.service.ForumMessageQueryService;
import com.jdon.jivejdon.service.ForumMessageService;
import com.jdon.strutsutil.FormBeanUtil;
import com.jdon.util.Debug;
import com.jdon.util.UtilValidate;

/**
 * @author <a href="mailto:[e-mail]">banq </a>
 *  
 */
public class ThreadPrevNexListAction extends Action {
    private final static String module = ThreadPrevNexListAction.class.getName();

    public ActionForward execute(ActionMapping actionMapping, ActionForm actionForm, HttpServletRequest request, HttpServletResponse response)
            throws Exception {

    	    	
        String currentThreadId = request.getParameter("thread");
        if ((UtilValidate.isEmpty(currentThreadId)) || (!UtilValidate.isInteger(currentThreadId))) {
            Debug.logError("require the paramters : currentThreadId ");
            return actionMapping.findForward(FormBeanUtil.FORWARD_SUCCESS_NAME);
        }
        try {
            Long currentThreadIdL = new Long(currentThreadId);
            ForumMessageQueryService forumMessageQueryService = (ForumMessageQueryService) WebAppUtil.getService("forumMessageQueryService", request);
            List threads = forumMessageQueryService.getThreadsPrevNext(currentThreadIdL);

            int index = -1;
            if (threads.size() != 0){
            	ForumMessageService forumMessageService = (ForumMessageService) WebAppUtil.getService("forumMessageService", request);
                ForumThread currentThread = forumMessageService.getThread(currentThreadIdL);
                index = threads.indexOf(currentThread);            	
            }
            Debug.logVerbose(" found the currentThread the index=" + index, module);
            
            //change the iterator for display
            ListIterator li = threads.listIterator();
            
            if (index != -1){
            	while (li.nextIndex() != index) {
                    Object o = li.next();                
                }	                
            }
            
            request.setAttribute("ThreadsPrevNext", li); //for above
            
            ListIterator li2 = threads.listIterator();
            if (index != -1){
                while (li2.nextIndex() != index) {                
                    Object o = li2.next();                
                }            	
            }
            request.setAttribute("ThreadsPrevNext2", li2);// for below
            
        } catch (Exception e) {
            Debug.logError(e, module);
        }
        return actionMapping.findForward(FormBeanUtil.FORWARD_SUCCESS_NAME);
    }

}