实现微信转账功能

package com.wx.view;

import java.util.Scanner;

import com.wx.Money;
import com.wx.User;
import com.wx.dao.WxDao;

public class Transfer {
    public static void main(String[] args) {
        System.out.println("*************微信转账模块**************");
        Scanner sc = new Scanner(System.in);
        System.out.print("请输入您的微信账号：");
        String uname = sc.next();
        System.out.print("请输入您的微信密码：");
        String pwd = sc.next();
        //判断用户名和密码的结果
        User u = new WxDao().checkLogin(uname, pwd);
        if(u!=null){
            //登陆成功
            System.out.println("恭喜您登陆成功！");
            System.out.println("用户名:"+u.getUname());
            //根据用户名获取用户账号金额
            Money m = new WxDao().getMoney(uname);
            System.out.println("账户余额："+m.getMoeny());
            //获取好友名称与金额
            System.out.print("请输入转账的好友名称：");
            String fname = sc.next();
            System.out.print("请输入转账金额：");
            double money = sc.nextDouble();
            //执行转账的操作
            new WxDao().Transfer(money, uname, fname);
            //重新查询账户金额
             m = new WxDao().getMoney(uname);
            System.out.println("转账成功！您的当前账户余额为"+m.getMoeny());
        }else{
            //登陆失败
            System.out.println("您的账号或密码输入错误!!");
        }
    }
}

package com.wx.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.wx.Money;
import com.wx.User;

public class WxDao {
    //校验用户名和密码
    public User checkLogin(String user,String pwd){
        PreparedStatement psmt = null;
        ResultSet rs = null;
        Connection con = null;
        User u = null;
        con = Tool.getConn2();
        try {
            //根据用户输入的用户名和密码查找是否有匹配的数据
            psmt = con.prepareStatement("select * from wx_user where uname=? and pwd = ?");
            psmt.setString(1, user);
            psmt.setString(2, pwd);
            rs = psmt.executeQuery();
            if(rs.next()){
                //将查询的用户名和密码封装到用户对象u中
                u= new User();    
                u.setUid(rs.getInt(1));
                u.setUname(rs.getString(2));
                u.setPwd(rs.getString(3));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            Tool.close(con, psmt);
        }
        return u;
    }
    
    //实现查询账户余额功能
        public Money getMoney(String user){
            PreparedStatement psmt = null;
            ResultSet rs = null;
            Connection con = null;
            Money m = new Money();
            con = Tool.getConn2();
            try {
                psmt = con.prepareStatement("select * from wx_money where uname=? ");
                psmt.setString(1, user);
                rs = psmt.executeQuery();
                if(rs.next()){
                    m.setUname(rs.getString(1));
                    m.setMoeny(rs.getDouble(2));
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                Tool.close(con, psmt);
            }
            return m;
        }
        //实现转账功能
        public  void Transfer(double money,String uname,String fname){
            PreparedStatement psmt = null;
            Connection con = null;
            con = Tool.getConn2();
            try {
                //减去用户账户中的金额
                psmt = con.prepareStatement("update wx_money set money=money-? where uname=? ");
                psmt.setDouble(1, money);
                psmt.setString(2, uname);
                psmt.executeUpdate();
                //增加好友账户中的金额
                psmt = con.prepareStatement("update wx_money set money=money+? where uname=? ");
                psmt.setDouble(1, money);
                psmt.setString(2, fname);
                psmt.executeUpdate();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
}

package com.wx.dao;


import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

public class Tool {
    

    public static Connection getConn2(){
        Connection conn = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection("jdbc:mysql://localhost/test","root","sys");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return conn;
    }
    
    
    public static void close(Connection con,PreparedStatement psmt){
        
        try {
            
            if(con!=null){
                con.close();
            }
            if(psmt!=null){
                psmt.close();
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }    
    }
}

package com.wx;

public class Money {
    String uname;
    double moeny;
    public String getUname() {
        return uname;
    }
    public void setUname(String uname) {
        this.uname = uname;
    }
    public double getMoeny() {
        return moeny;
    }
    public void setMoeny(double moeny) {
        this.moeny = moeny;
    }
    
}

package com.wx;

public class User {
    int uid;
    String uname;
    String pwd;
    public int getUid() {
        return uid;
    }
    public void setUid(int uid) {
        this.uid = uid;
    }
    public String getUname() {
        return uname;
    }
    public void setUname(String uname) {
        this.uname = uname;
    }
    public String getPwd() {
        return pwd;
    }
    public void setPwd(String pwd) {
        this.pwd = pwd;
    }
    
}