messagedao.java

简单的SREVLET的实验项目 大家可以下载试用一下看看或许有什么帮助

package com.zg.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import com.zg.bean.MessageBean;
import com.zg.util.DBConn;

public class MessageDAO {
	
	public static List selectMess(){

		List list = new ArrayList();
		Connection conn =  DBConn.getConn();
		
		PreparedStatement pst = null;
		ResultSet rs = null;
		
		String sql = "select * from message order by fabutime desc";
		
		try {
			pst = conn.prepareStatement(sql);
			
			rs = pst.executeQuery();
			
			while(rs.next()){
				
				MessageBean mbean = new MessageBean();
				
				mbean.setMessageid(rs.getInt(1));
				mbean.setUsername(rs.getString(2));
				mbean.setBiaoti(rs.getString(3));
				mbean.setFabutime(rs.getString(4));
				mbean.setContent(rs.getString(5));
				
				list.add(mbean);
				
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally{
			try {
				rs.close();
				pst.close();
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		
		return list;
	}
	/***
	 * 插入留言
	 * @return
	 */
   public static boolean addContent(MessageBean mbean){
	   boolean flag = false;
	   Connection conn = DBConn.getConn();
	   PreparedStatement pst = null;
	   
	   String sql = "insert into message values(?,?,?,?)";
	   
	   try {
		pst = conn.prepareStatement(sql);
		
		pst.setString(1, mbean.getUsername());
		pst.setString(2,mbean.getBiaoti());
		pst.setString(3, new Date().toLocaleString().toString());
		pst.setString(4,mbean.getContent());
		
		int x = pst.executeUpdate();
		
		if(x>0){
			flag = true;
		}
		
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
	   finally{
		   
		   try {
			pst.close();
			conn.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		   
	   }
	   
	   return flag;
   }
}