chargesqldaoimpl.java

开发的一个java web的任务管理系统。

/**
 * 备注:
 */
package unicom.dao;

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

import unicom.bean.Charge;
import unicom.util.DBUtil;

/**
 * @author xiaogang
 * 日期：Apr 18, 2008
 * 功能：实现IChargeDao接口，封装具体数据库访问操作
 * 优点：
 * 缺点：
 * 建议：
 */
public class ChargeSqlDaoImpl implements IChargeDao {
    //将数据库中TCharge记录以Charge对象存入List中
	public List getChargeList() {
      List chargeList = new ArrayList();
      String sql = "select code,name,charge from TCharge order by code";
      Connection conn = DBUtil.getConn();
      Statement stmt = DBUtil.getStatement(conn);
      ResultSet rs = DBUtil.getResultSet(stmt, sql);     
      try {
		while(rs.next())
		  {
			  Charge charge = new Charge();
			  charge.setCode(rs.getString(1));
			  charge.setName(rs.getString(2));
			  charge.setCharge(rs.getDouble(3));
			  chargeList.add(charge);
		  }
	} catch (SQLException e) {
		e.printStackTrace();
	}finally{
		//释放数据库资源
		DBUtil.close(rs);
		DBUtil.close(stmt);
		DBUtil.close(conn);
	}
      return chargeList;
	}
    
	//由TCharge的code查询charge并返回
	public double getChargePriceByCode(String code)
	{
		double price = 0;
		String sql = "select charge from TCharge where code = '" + code + "'";
		Connection conn = DBUtil.getConn();
		Statement stmt = DBUtil.getStatement(conn);
		ResultSet rs = null;
		try {
			rs = stmt.executeQuery(sql);
			while(rs.next())
			{
				price = rs.getDouble(1);
			}
			
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return price;
	}
   
    //修改TCharge表的charge值
	public boolean updateCharge(String code, double charge) {
		boolean flag = true;
		String sql = "update TCharge set charge = '" + charge + "' where code = '" + code + "'";
		Connection conn = DBUtil.getConn();
		Statement stmt = DBUtil.getStatement(conn);
        try{
		DBUtil.executeUpdate(stmt, sql);
        }catch(Exception e)
        {
        	e.printStackTrace();
        	flag = false;
        }
		return flag;
	}
   
}