mysqltchargedao.java

这是我在东方标准学习的时候做的一个项目

package dao.product.mysql;

import java.sql.*;
import java.util.*;

import dao.product.DbUtil;
import dao.product.TChargeDAO;
import bean.*;

public class MySQLTChargeDAO implements TChargeDAO
{
	public boolean add(TCharge charge)
	{
		DbUtil db = new MySQLDbUtil();
		Connection conn = db.getConnection();
		String sql = "insert into TCharge values(?,?,?)";
		try {
			PreparedStatement prepStmt = conn.prepareStatement(sql);
			prepStmt.setString(1, charge.getCharge_code());
			prepStmt.setString(2,charge.getCharge_name());
			prepStmt.setDouble(3,charge.getCharge());
			prepStmt.executeUpdate();
			return true;
		} catch (SQLException e) {
			e.printStackTrace();
			return false;
		} finally {
			db.close();
		}
	}	
	public Boolean update(TCharge charge){
		DbUtil db = new MySQLDbUtil();
		Connection conn = db.getConnection();
		String sql = "update TCharge set charge_name=?, charge=? where charge_code=?";
		try {
			PreparedStatement prepStmt = conn.prepareStatement(sql);
			prepStmt.setString(1,charge.getCharge_name());
			prepStmt.setDouble(2,charge.getCharge());
			prepStmt.setString(3, charge.getCharge_code());
			prepStmt.execute();
			return true;
		} catch (SQLException e) {
			e.printStackTrace();
			return false;
		} finally {
			db.close();
		}
	}
	
	public Boolean delete(String charge_code){
		DbUtil db = new MySQLDbUtil();
		Connection conn = db.getConnection();
		String sql = "delete TCharge where charge_code=?";
		try
		{	
			PreparedStatement prepStmt = conn.prepareStatement(sql);
			prepStmt.setString(1,charge_code);
			prepStmt.execute();
			return true;
		} catch (SQLException e) {
			e.printStackTrace();
			return false;
		} finally {
			db.close();
		}
	}
	
	public TCharge findByCharge_code(String charge_code){
		TCharge p = null;
		DbUtil db = new MySQLDbUtil();
		String sql = "select * from TCharge where charge_code='"+charge_code+"'";
		ResultSet rs = db.executeQuery(sql);
		try
		{
			while(rs.next())
			{
				p = new TCharge();
				p.setCharge(rs.getInt("charge"));
				p.setCharge_code(rs.getString("charge_code"));
				p.setCharge_name(rs.getString("charge_name"));
			}
		}
		catch (SQLException e)
		{
			e.printStackTrace();
		}
		finally
		{
			db.close();
		}
		return p;
	}
	
	public List findAll(){
		List<TCharge> list = new ArrayList<TCharge>();
		DbUtil db = new MySQLDbUtil();
		String sql = "select * from TCharge";
		ResultSet rs = db.executeQuery(sql);
		try
		{
			while(rs.next())
			{
				TCharge p = new TCharge();
				p = new TCharge();
				p.setCharge(rs.getInt("charge"));
				p.setCharge_code(rs.getString("charge_code"));
				p.setCharge_name(rs.getString("charge_name"));	
				list.add(p);
			}
		}
		catch (SQLException e)
		{
			e.printStackTrace();
		}
		finally
		{
			db.close();
		}
		return list;
	}
}