topicdao.java

用java实现的一个论坛,可以供大家参考

/*******************************************************************\
*                                                                   *
*			   LightningBoard			    *
*                                                                   *
*          http://sourceforge.net/projects/lightningboard/          *
*			                                            *
*	            Copyright (c) 2002 Xiaobo Liu	            *
*                                                                   *
*********************************************************************
*                        LICENSE INFORMATION                        *
*                                                                   *
*  LightningBoard is free software; you can redistribute it and/or  *
*  modify it under the terms of the GNU General Public License as   *
*  published by the Free Software Foundation; either version 2 of   *
*  the License, or any later version.                               *
*                                                                   *
*  We don't charge anything for the use of LightningBoard, we only  *
*  require you to keep the copyright present on your site and in    *
*  the source files.                                                *
*                                                                   *
*  LightningBoard is distributed in the hope that it will be useful,*
*  but without any warranty; without even the implied warranty of   *
*  merchantability or fitness for a particular purpose. See the GNU *
*  General Public License for more details.                         *
*                                                                   *
\*******************************************************************/

package liuxiaobo.lb.dao;

import java.sql.*;
import java.util.*;
import liuxiaobo.db.*;
import liuxiaobo.lb.*;
import liuxiaobo.lb.bean.*;

public class TopicDAO  {
  private DBConnectionManager dbcm = DBConnectionManager.getInstance();

  public TopicBean execute(int t_id)throws ActionException{
    Connection connection=null;
    try {
      TopicBean topicBean=new TopicBean();
      connection=dbcm.getConnection();
      DBAccess dba=new DBAccess(connection);
      String sql="SELECT t_f_id,f_name,f_info,f_u_id,u_name,f_topics,f_messages,t_name,t_replies,t_views FROM forum,topic,user  WHERE t_f_id=f_id AND f_u_id=u_id  AND t_id=" + t_id;
      ResultSet rs=dba.openSelect(sql);
      //check result
      if (!rs.next())
        return null;
      rs.beforeFirst();
      while (rs.next()){
        topicBean.setF_id(rs.getString("t_f_id"));
        topicBean.setF_name(rs.getString("f_name"));
        topicBean.setF_info(rs.getString("f_info"));
        topicBean.setF_u_id(rs.getString("f_u_id"));
        topicBean.setU_name(rs.getString("u_name"));
        topicBean.setF_topics(rs.getString("f_topics"));
        topicBean.setF_messages(rs.getString("f_messages"));
        topicBean.setT_id(String.valueOf(t_id));
        topicBean.setT_name(rs.getString("t_name"));
        topicBean.setT_replies(rs.getString("t_replies"));
        topicBean.setT_views(rs.getString("t_views"));
      }
      rs.close();
      dba.closeSelect();
      //------------------------
      sql="SELECT m_id,m_content,m_time,m_u_id,u_name,u_regtime,u_address,u_post,u_sign FROM message,user  WHERE m_u_id=u_id AND m_t_id=" + t_id + " ORDER BY m_time";
      rs = dba.openSelect(sql);
      //check result
      if (!rs.next())
        return null;
      rs.beforeFirst();
      List messageList=new LinkedList();
      while(rs.next()){
        Message message=new Message();
        message.setM_id(rs.getString("m_id"));
        message.setM_content(rs.getString("m_content"));
        message.setM_time(rs.getString("m_time"));
        message.setM_u_id(rs.getString("m_u_id"));
        message.setU_name(rs.getString("u_name"));
        message.setU_regtime(rs.getString("u_regtime"));
        message.setU_address(rs.getString("u_address"));
        message.setU_post(rs.getString("u_post"));
        message.setU_sign(rs.getString("u_sign"));
        messageList.add(message);
      }
      topicBean.setMessages(messageList);
      rs.close();
      dba.closeSelect();
      //view
      dba.runSql("UPDATE topic SET t_views=t_views+1 WHERE t_id="+t_id);
      //jump
      CommonDAO commonDAO=new CommonDAO();
      topicBean.setForumMap(commonDAO.getForumMap(dba));
      return topicBean;
    } catch (Exception ex) {
      throw new ActionException(ex);
    }finally{
      try {
        dbcm.freeConnection(connection);
      } catch (SQLException ex) {
        //
      }
    }
  }
}