vipmanager.java

java编写小型超市管理系统+数据库.用于小型超市简单的货品进存销

package com.wish;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Vector;
//VIP用户管理类。增加，删除，等等。
public class VipManager {

	@SuppressWarnings("unchecked")
	public Vector getUser()
	{
		Vector v =new Vector();
		Connection cn=ConnectionDB.getCon();
		Statement st=null;
		ResultSet rs=null;
		
		try {
			String sql="select * from userlist";
			st=cn.createStatement();
			rs=st.executeQuery(sql);
			while(rs.next())
			{	User user=new User();
				String user_id=rs.getString("user_id");
				String user_name=rs.getString("user_name");
				String user_date=rs.getString("user_date");
				String user_buy=rs.getString("user_buy");
				String user_pay=rs.getString("user_pay");
				
				user.setUser_id(user_id);
				user.setUser_name(user_name);
				user.setUser_date(user_date);
				user.setUser_buy(user_buy);
				user.setUser_pay(user_pay);
				
				v.add(user);
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
			ConnectionDB.close(rs);
			ConnectionDB.close(st);
			ConnectionDB.close(cn);
		return v;
	}
	@SuppressWarnings("unchecked")
	public Vector get1(String n)
	{
		Vector v =new Vector();
		Connection cn=ConnectionDB.getCon();
		Statement st=null;
		ResultSet rs=null;
		
		try {
			String sql="select user_name,user_pay from userlist where user_id='"+n+"'";
			st=cn.createStatement();
			rs=st.executeQuery(sql);
			if(rs.next())
			{	User user=new User();
				user.setUser_name(rs.getString("user_name"));
				user.setUser_pay(rs.getString("user_pay"));
				v.add(user);
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
			ConnectionDB.close(rs);
			ConnectionDB.close(st);
			ConnectionDB.close(cn);
		return v;
	}
//	删除方法
	public boolean delUser(String user_id)
	   {
		   boolean flag = false;
		   Connection cn = ConnectionDB.getCon();
		   String delSql = "delete from userlist where user_id= ?";
		   try {
			PreparedStatement ps = cn.prepareStatement(delSql);
			ps.setString(1,user_id);
			int n=ps.executeUpdate();
			if(n>0)flag = true;
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return flag;
	   }
	//插入方法
	public boolean addUser(String[]data)
	   {
		   boolean flag = false;
		   Connection cn = ConnectionDB.getCon();
		   String addSql = "insert into userlist values(?,?,?,?,?)";
		   try {
			PreparedStatement ps = cn.prepareStatement(addSql);
			for(int i=1;i<=5;i++)
			ps.setString(i,data[i-1]);
			int n=ps.executeUpdate();
			if(n>0)flag = true;
		} catch (SQLException e) {
			e.printStackTrace();
		}
		   return flag;
	   }
	   //更新方法
	   public void updateUser(User user)
	   {
		   Connection cn = ConnectionDB.getCon();
		   String updSql = "update userlist set user_name=?,user_date=?,user_buy=?,user_pay=? where user_id=?";
		   try {
			PreparedStatement ps = cn.prepareStatement(updSql);
			ps.setString(1,user.getUser_name());
			ps.setString(2,user.getUser_date());
			ps.setString(3,user.getUser_buy());
			ps.setString(4,user.getUser_pay());
			ps.setString(5,user.getUser_id());
			ps.executeUpdate();
		} catch (SQLException e) {
			e.printStackTrace();
		}
	   }
}