topicoperateservlet.java

这是一个内容管理系统（CMS）以MVC方式写出,没有使用框架

package servlet.article;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;

import main.*;

/**
 * Servlet implementation class for Servlet: TopicOperateServlet
 *
 */
 public class TopicOperateServlet extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
    /* (non-Java-doc)
	 * @see javax.servlet.http.HttpServlet#HttpServlet()
	 */
		DBControl DC=new DBControl();//定义一个数据库操作对像
		RequestDispatcher rd=null;//跳转页面
	public TopicOperateServlet() {
		super();
	}   	
	
	/* (non-Java-doc)
	 * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.setContentType("text/html;charset=gb2312");
		request.setCharacterEncoding("gb2312");
		String action=request.getParameter("action");
		String Id=request.getParameter("Id");
		
		String sql="";
		try
		{
			DC.getConnPool();
			if(action.trim().equals("delete"))
			{
				ArticleClearTopic(Id);
				sql="delete from topic where Id="+String.valueOf(Id);
				DC.ExecuteSQL(sql);	
			}
			else if(action.trim().equals("clear"))
			{
				ArticleClearTopic(Id);
			}
			else if(action.trim().equals("orderup"))
			{
				DC.OrderUpOne("topic", "OrderList", Integer.valueOf(Id));
			}
			else if(action.trim().equals("orderdown"))
			{
				DC.OrderDownOne("topic", "OrderList", Integer.valueOf(Id));
			}
		}catch(Exception ex)
		{
			System.out.println("MenuOperateServlet中出错：执行动作为"+action+ex);
		}
		finally
		{
			DC.closeAll();
			rd=request.getRequestDispatcher("/jsjadmin/Menu/Topic_manager.jsp");
			rd.forward(request, response);
		}
	}  	
	
	private void ArticleClearTopic(String Id)//根据专题的ID，清除专题文章的专题
	{
		ResultSet rs=null;
		DealString dstr=new DealString();
		String sql="select Id,TopicID from article where TopicID<>''";
		try
		{
			rs=DC.QuerySQL(sql);
			while(rs.next())
			{
				String[] TopicIds=dstr.splitStr(rs.getString("TopicID"), '|');
				int index;
				for(index=0;index<TopicIds.length;index++)
				{
					if(TopicIds[index].trim().equals(Id))
					{
						break;
					}
				}
				if(index!=TopicIds.length)
				{
					String newTopicId="";
					for(int i=0;i<TopicIds.length;i++)//去掉专题集中的Id
					{
						if(i!=index)
						{
							newTopicId+=TopicIds[i].trim()+"|";
						}
					}
					if(newTopicId.length()>0)
					{
						newTopicId=newTopicId.substring(0, newTopicId.length()-1);//删除最后一个“|”
					}
					sql="update article set TopicID='"+newTopicId.trim()+"' where Id="+rs.getString("Id");
					PreparedStatement pstm=null;
					try
					{
						pstm=DC.conn.prepareStatement(sql);
						pstm.executeUpdate();
					}catch(SQLException  ex)
					{
						System.out.println("在清除文章中的专题时出错："+sql+ex);
					}
					finally
					{
						pstm.close();
					}
				}
			}
		}catch(SQLException  ex)
		{
			System.out.println("在清除文章中的专题时出错："+ex);
		}
		finally
		{
			DC.closeResault();
			DC.closePstm();
		}
		
	}
}