手记

学完java基础以及MySQL后再回来尝试哒哒租车系统

一共调用了4个外界类库,
分别为:
mysql-connector-java-5.1.37
commons-dbutils-1.6
commons-dbcp-1.4
commons-pool-1.5.6

具体代码如下:

package com.ewarm.domain;

public class Car {
    //JavaBean类
    private int carid;
    private String carname;
    private int price;
    private int takeman;
    private int takecargo;
    public Car() {}
    public Car(int carid, String carname, int price, int takeman, int takecargo) {
        super();
        this.carid = carid;
        this.carname = carname;
        this.price = price;
        this.takeman = takeman;
        this.takecargo = takecargo;
    }
    public String toString() {
        return "Car [carid=" + carid + ", carname=" + carname + ", price=" + price + ", takeman=" + takeman
                + ", takecargo=" + takecargo + "]";
    }
    public int getCarid() {
        return carid;
    }
    public void setCarid(int carid) {
        this.carid = carid;
    }
    public String getCarname() {
        return carname;
    }
    public void setCarname(String carname) {
        this.carname = carname;
    }
    public int getPrice() {
        return price;
    }
    public void setPrice(int price) {
        this.price = price;
    }
    public int getTakeman() {
        return takeman;
    }
    public void setTakeman(int takeman) {
        this.takeman = takeman;
    }
    public int getTakecargo() {
        return takecargo;
    }
    public void setTakecargo(int takecargo) {
        this.takecargo = takecargo;
    }

}
package com.ewarm.tools;

import javax.sql.DataSource;

import org.apache.commons.dbcp.BasicDataSource;

public class JDBCUtil {
    /*
     * 自制工具类
     * 方便调用数据库连接池
     */

    private static BasicDataSource datasource = new BasicDataSource();

    private JDBCUtil(){}

    static{
        //初始化连接池设置
        datasource.setDriverClassName("com.mysql.jdbc.Driver");
        datasource.setUrl("jdbc:mysql://localhost:3306/ddzc");
        datasource.setUsername("root");
        datasource.setPassword("123");
    }

    //静态方法供外界调用
    public static DataSource getBasicDataSource(){
        return datasource;
    }
}
package com.ewarm.app;

import com.ewarm.view.MainView;

public class DoMain {
    /*
     * 主方法入口
     */
    public static void main(String[] args) {
        new MainView().run();
    }

}
package com.ewarm.dao;

import java.sql.SQLException;
import java.util.List;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;

import com.ewarm.domain.Car;
import com.ewarm.tools.JDBCUtil;

public class Dao {
    /*
     * 数据层
     */
    //声明使用连接池链接数据库的的结果集 qr
    private QueryRunner qr = new QueryRunner(JDBCUtil.getBasicDataSource());

    //查询数据库所有数据
    public List<Car> selectAll() {
        try{
            String sql = "SELECT * FROM car";
            //得到数据库每条数据封装到JavaBean对象中,再将这些对象封装到List集合中
            List<Car> list = qr.query(sql, new BeanListHandler<>(Car.class));
            return list;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }

    //构建字符串,保证sql语句的完整性
    public StringBuffer getStringBuffer(int[] arr){
        StringBuffer sfd = new StringBuffer();
        for(int i=0 ; i<arr.length ; i++){
            if(i==(arr.length-1)){
                sfd.append(arr[i]);
            }else{
                sfd.append(arr[i]+",");
            }
        }
        return sfd;
    }

    //查询数据库指定编号的车辆的总金额
    public Object selectCar_price(int[] arr) {
        try{
            StringBuffer sfd = getStringBuffer(arr);
            String sql = "SELECT SUM(price) FROM car WHERE carid IN("+sfd+")";
            //得到数据库的单数据
            Object obj= qr.query(sql, new ScalarHandler<Object>());
            return obj;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }

    //查询数据库指定编号的车辆的总共载客数
    public Object selectCar_takeman(int[] arr) {
        try{
            StringBuffer sfd = getStringBuffer(arr);
            String sql = "SELECT SUM(takeman) FROM car WHERE carid IN("+sfd+")";
            //得到数据库的单数据
            Object obj = qr.query(sql, new ScalarHandler<Object>());
            return obj;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }
    //查询数据库指定编号的车辆的总共载货数
    public Object selectCar_takecargo(int[] arr) {
        try{
            StringBuffer sfd = getStringBuffer(arr);
            String sql = "SELECT SUM(takecargo) FROM car WHERE carid IN("+sfd+")";
            //得到数据库的单数据
            Object obj = qr.query(sql, new ScalarHandler<Object>());
            return obj;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }

    //查询数据库指定编号的客车总数 ,只要能载客就列入
    public List<Car> selectCar_takemanCar(int[] arr) {
        try{
            StringBuffer sfd = getStringBuffer(arr);
            String sql = "SELECT carname FROM car WHERE carid IN("+sfd+") AND takeman<>0";
            //得到数据库每条数据封装到JavaBean对象中,再将这些对象封装到List集合中
            List<Car> list = qr.query(sql, new BeanListHandler<>(Car.class));
            return list;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }
    //查询数据库指定编号的货车总数,只能载货物
    public List<Car> selectCar_takecargoCar(int[] arr) {
        try{
            StringBuffer sfd = getStringBuffer(arr);
            String sql = "SELECT carname FROM car WHERE carid IN("+sfd+") AND takeman=0";
            //得到数据库每条数据封装到JavaBean对象中,再将这些对象封装到List集合中
            List<Car> list = qr.query(sql, new BeanListHandler<>(Car.class));
            return list;
        }catch(SQLException ex){
            System.out.println(ex);
            throw new RuntimeException("数据查询异常");
        }
    }

}
package com.ewarm.view;

import java.util.List;
import java.util.Scanner;

import com.ewarm.dao.Dao;
import com.ewarm.domain.Car;

public class MainView {
    /*
     * 视图层
     */
    private Dao dao = new Dao();

    public void run(){
        //创建键盘录入对象
        Scanner sc = new Scanner(System.in);
        while(true){
            //主界面
            System.out.println("欢迎使用哒哒租车系统:");
            System.out.println("您是否要租车:1是 0否");
            int choose = sc.nextInt();
            switch (choose) {
            case 1:
                //进入租车系统
                rentCar();
                break;
            case 0:
                //退出系统
                System.out.println("谢谢使用");
                sc.close();
                System.exit(0);
                break;
            default:
                break;
            }
        }
    }
    public void rentCar(){
        //显示可租车的类型及其价目表
        showCar();
        //选择租车型号与天数
        chooseCar();
    }

    private void chooseCar() {

        @SuppressWarnings("resource")
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入要租的车的数量:");
        int count = sc.nextInt();
        int[] arr = new int[count];

        //获取选择车辆数组id;
        for(int i=0;i<count;i++){
            System.out.println("请输入第"+(i+1)+"辆车的序号:");
            arr[i] = sc.nextInt();
        }
        //查询得到金钱总数的返回值
        Object arr_price = dao.selectCar_price(arr);
        //查询得到载人总数的返回值
        Object arr_takeman = dao.selectCar_takeman(arr);
        //查询得到载货总数的返回值
        Object arr_takecargo = dao.selectCar_takecargo(arr);

        //查询得到载客类车种集合
        List<Car> list1 = dao.selectCar_takemanCar(arr);
        //获得结果字符串
        StringBuffer sbf1 = new StringBuffer();
        for(Car car : list1){
            if(car.getCarname()==null)
                sbf1.append("无该类车辆");
            sbf1.append(car.getCarname()+"\t");
        }
        //查询得到载货类车种集合
        List<Car> list2 = dao.selectCar_takecargoCar(arr);
        //获得结果字符串
        StringBuffer sbf2 = new StringBuffer();
        for(Car car : list2){
            if(car.getCarname()==null)
                sbf1.append("无该类车辆");
            sbf2.append(car.getCarname()+"\t");
        }

        //总单价*租车天数得到总金额
        System.out.println("请输入租车天数:");
        int sentday = sc.nextInt();
        int i = Integer.parseInt(arr_price.toString());
        int allprice = sentday*i;

        System.out.println("***账单***");
        System.out.println("您选择的载客类车种为:"+sbf1);
        System.out.println("您选择的载货类车种为:"+sbf2);
        System.out.println("共载人:"+arr_takeman+"人");
        System.out.println("***共载货物:"+arr_takecargo+"吨");
        System.out.println("***租车总价格为:"+allprice);

        //System.exit(0);

    }

    public void showCar(){
        //调用dao类方法 查询数据库
        List<Car> list = dao.selectAll();
        System.out.println("您可租车的类型及其价目表:");
        System.out.println("序号\t汽车名称\t租金\t\t容量");
        //遍历查询数据库得到的集合list
        for(Car car : list){
            if(car.getTakecargo()==0){
                System.out.println(car.getCarid()+"\t"+car.getCarname()+"\t"+car.getPrice()+"元/天\t\t载人:"+car.getTakeman()+"人");
            }else if(car.getTakeman()==0){
                System.out.println(car.getCarid()+"\t"+car.getCarname()+"\t"+car.getPrice()+"元/天\t\t载货:"+car.getTakecargo()+"吨");
            }else{
                System.out.println(car.getCarid()+"\t"+car.getCarname()+"\t"+car.getPrice()+"元/天\t\t载人:"+car.getTakeman()+"人  "+car.getTakecargo()+"吨");
            }
        }

    }
}

数据库初始化语句如下:

CREATE DATABASE ddzc;
USE ddzc;
CREATE TABLE car(
   carid INT PRIMARY KEY AUTO_INCREMENT,
   carname VARCHAR(10),
   price INT,
   takeman INT,
   takecargo INT
);
SELECT * FROM car;

INSERT INTO car(carname,price,takeman,takecargo) VALUE('奥迪A4',500,4,0);
INSERT INTO car(carname,price,takeman,takecargo) VALUE('马自达6',400,4,0);
INSERT INTO car(carname,price,takeman,takecargo) VALUE('皮卡雪6',450,4,2);
INSERT INTO car(carname,price,takeman,takecargo) VALUE('金龙',800,20,0);
INSERT INTO car(carname,price,takeman,takecargo) VALUE('松花江',400,0,4);
INSERT INTO car(carname,price,takeman,takecargo) VALUE('依维柯',1000,0,20);

具体控制台如下:

7人推荐
随时随地看视频
慕课网APP