306ac91ad086001d11f1f36e3a353717

一个相对比较简单的留言簿！功能还比较齐全！

package com.pure35.database;
import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import com.pure35.vo.MessageVo;


public class MessageDao {
	Connection con=null;
	PreparedStatement pm=null;
	ResultSet rs;
	String sql="";
	MessageVo message;
	
	public void addMessage(String sql){
		try {
			con=DBConn.getConnection();//连接数据库
			pm=con.prepareStatement(sql);
			
		
		    
			pm.executeUpdate();
			
		} catch (SQLException e) {
			
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			DBConn.closeConnection();
			
		}
		
	}
	
	public List queryUser(String sql ){
		List list=new ArrayList();
    	try {
    		con=DBConn.getConnection();
			pm=con.prepareStatement(sql);
			rs=pm.executeQuery();
			while(rs.next()){
				
				int id=rs.getInt("id");;
			    String subject=rs.getString("subject");
				 Date  mdate=rs.getDate(3);
				 String username=rs.getString("userrname");
				 String content=rs.getString("content");
				
				message=new MessageVo();
				message.setContent(content);
				message.setId(id);
				message.setMdate(mdate);
				message.setUsername(username);
				message.setSubject(subject);				
				list.add(message);
				
			}
			
		} catch (SQLException e) {
			
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			try {
				rs.close();
				pm.close();
				DBConn.closeConnection();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		
		
		}
    	
		
		return list;
	}
	
	public void UpdateUser(String sql){
		
		
		con=DBConn.getCon();//连接数据库
    	
    	
		try {
			pm=con.prepareStatement(sql);
			
		
			pm.executeUpdate();
			
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			try {
				pm.close();
				DBConn.closeConnection();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		
		}
    	
		
	}
	
	public void DeleteUser(String sql){
		con=DBConn.getCon();//连接数据库
    	

		
		try {
			pm=con.prepareStatement(sql);
			
			pm.executeUpdate();
			
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			try {
				pm.close();
				DBConn.closeConnection();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		
		}
    	
	}

}