分包

view層做用: 視圖層,即項目中的界面

 controller層做用: 控制層, 獲取界面上的數據,爲界面設置數據; 將要實現的功能交給業務層處理

 service層做用: 業務層, 功能的實現, 與controller控制層和數據訪問層DAO交互, 將對數據庫的操做交給DAO數據訪問層來處理

dao層做用: 數據訪問層, 用來操做數據庫表的數據

 db數據庫: 這裏指MySQL

 domain 實體包: 存放JavaBean

 tools工具包:存放項目中使用到的工具類

 test 測試包: 存放項目功能測試的代碼

 

 以商店帳戶管理，貨物管理功能爲例簡歷的java項目

dao層鏈接數據庫數據庫語句--------------》service層 功能的實現-----------------------》controller層---------------view層

tools：裝的是JDBCUtils

package tools;

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


public class JDBCUtils {
    public static Connection getConn() {
        // 1.註冊驅動
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // 2.得到鏈接對象
        String url = "jdbc:mysql://localhost:3306/smalmarket?characterEncoding=utf-8";
        String username = "root";
        String password = "123";
        Connection conn=null;
        try {
            conn = DriverManager.getConnection(url, username, password);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return conn;
    }
    public static void close(Connection conn,PreparedStatement pst){
        if(pst!=null){
            try {
                pst.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
    public static void close(Connection conn,
            PreparedStatement pst,ResultSet rs){
        if(rs!=null){
            try {
                rs.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(pst!=null){
            try {
                pst.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

 

 view層：

package view;
import java.util.List;
import java.util.Scanner;
import controller.SortController;
import controller.UserController;
import domain.Sort;
public class MainView {
    private UserController userController=new UserController();
    private SortController sortController=new SortController();
    public void MainShow(){
        System.out.println("-----歡迎進入商城-----");
        System.out.println("一、登錄");
        System.out.println("二、註冊");
        System.out.println("三、退出");
        System.out.println("四、請輸入您的選擇");    
    }
    public void IndexShow(){
        System.out.println("----首頁----");
        System.out.println("一、新增分類");
        System.out.println("二、修改分類");
        System.out.println("三、刪除分類");
        System.out.println("四、查詢全部分類");
        System.out.println("五、返回上級菜單");
        System.out.println("六、請輸入您的選擇");
    }
    //登錄
    public void login(){
        System.out.println("----登陸頁面----");
        System.out.println("請輸入用戶名");
        Scanner sc=new Scanner(System.in);
        String username=sc.next();
        System.out.println("請輸入密碼");
        String password=sc.next();
        //調用Controller層的登陸方法
        int count=userController.login(username,password);
        if(count>0){
            System.out.println("登錄成功");
            run2();
        }else{
            System.out.println("登錄失敗！");
        }
    }
    //一級菜單
    public void run(){
        Scanner sc=new Scanner(System.in);
        while(true){
            MainShow();
            int choose=sc.nextInt();
            switch(choose){
            case 1:
                login();
                break;
            case 2:register();
                break;
            case 3:
                System.out.println("退出成功");
                return;
            }
        }
    }
    //二級菜單
    public void run2(){
        Scanner sc=new Scanner(System.in);
        while(true){
            IndexShow();
            int choose=sc.nextInt();
            switch(choose){
            case 1:addSort();
                break;
            case 2:update();
                break;
            case 3:delete();
                break;
            case 4:getall();
                break;
            case 5:
                return;
            }
        }
    }
    //新增分類頁面
    public void addSort(){
        Scanner sc=new Scanner(System.in);
        System.out.println("=====新增頁面====");
        System.out.println("請輸入你要新增的分類名稱");
        String sname=sc.next();
        //調用controller新增分類的方法
        String mes=sortController.addSort(sname);
        System.out.println(mes);
        
    }
    //查詢全部分類頁面
    public void getall(){
        System.out.println("查詢全部分類");
        //調用Controller調用方法
        List<Sort>list=sortController.getall();
        System.out.println("分類編號\t分類名稱");
        for(Sort s:list){
            System.out.println(s.getSid()+"\t"+s.getSname());
        }
    }
    //修改分類頁面
    public void update(){
        getall();
        System.out.println("請輸入您要修改的分類編號");
        Scanner sc=new Scanner(System.in);
        int sid=sc.nextInt();
        System.out.println("請輸入您要修改的分類名稱");
        String sname=sc.next();
        //調用 controller方法
        String mes=sortController.updateSort(sid, sname);
        System.out.println(mes);
    }
    //刪除元素
    public void delete(){
        getall();
        System.out.println("請輸入您要刪除的分類編號");
        Scanner sc=new Scanner(System.in);
        int sid=sc.nextInt();
        //調用controller方法
        String mes=sortController.deleteSort(sid);
        System.out.println(mes);
    }
    //註冊
    public void register(){
        System.out.println("----註冊頁面----");
        System.out.println("請輸入您要註冊的用戶名");
        Scanner sc=new Scanner(System.in);
        int count=1;
        String uname=null;
        
        while(count>0){
        uname=sc.next();
        //調用controller的驗證用戶名是否已存在
        count=userController.checkUsername(uname);
        if(count>0){
            System.out.println("用戶已存在，請從新輸入");
        }
        }
        System.out.println("請輸入密碼");
        String pwd=sc.next();
        //調用controller方法
        String mes=userController.register(uname,pwd);
        System.out.println(mes);
    }
}

 

 

package dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import domain.User;
import tools.JDBCUtils;
public class UserDao {
    //登陸驗證用戶名或密碼是否正確
    public  int login(String username,String password) throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="select count(*) from user where uname=? and pwd=?";
        PreparedStatement pst=conn.prepareStatement(sql);
        pst.setString(1, username);
        pst.setString(2, password);
        ResultSet rs=pst.executeQuery();
        int count=0;
        while(rs.next()){
            count=rs.getInt(1);
        }
        return count;
    }
    //驗證用戶名是否重複
public int checkUsername(String uname) throws SQLException{
    Connection conn=JDBCUtils.getConn();
    String sql="select count(*) from user where uname=?";
    PreparedStatement pst=conn.prepareStatement(sql);
    pst.setString(1, uname);
    ResultSet rs=pst.executeQuery();
    //處理結果集
    int count=0;
        while(rs.next()){
            count=rs.getInt(1);
            }
    JDBCUtils.close(conn, pst,rs);
    return count;    
    }
//註冊
public int register(User user) throws SQLException{
    Connection conn=JDBCUtils.getConn();//數據庫鏈接語句
    String sql="insert into user(uname,pwd) values(?,?)";
    PreparedStatement pst=conn.prepareStatement(sql);//sql語句注入問題（1'or'1=1）
    pst.setString(1, user.getUname());//第一個問號，的值是user.getUname()，從1開始
    pst.setString(2, user.getPwd());
    int row = pst.executeUpdate();
    JDBCUtils.close(conn, pst);//釋放資源，
    return row;    
    }
}

package dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import domain.User;
import tools.JDBCUtils;
public class UserDao {
    //登陸驗證用戶名或密碼是否正確
    public  int login(String username,String password) throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="select count(*) from user where uname=? and pwd=?";
        PreparedStatement pst=conn.prepareStatement(sql);
        pst.setString(1, username);
        pst.setString(2, password);
        ResultSet rs=pst.executeQuery();
        int count=0;
        while(rs.next()){
            count=rs.getInt(1);
        }
        return count;
    }
    //驗證用戶名是否重複
public int checkUsername(String uname) throws SQLException{
    Connection conn=JDBCUtils.getConn();
    String sql="select count(*) from user where uname=?";
    PreparedStatement pst=conn.prepareStatement(sql);
    pst.setString(1, uname);
    ResultSet rs=pst.executeQuery();
    //處理結果集
    int count=0;
        while(rs.next()){
            count=rs.getInt(1);
            }
    JDBCUtils.close(conn, pst,rs);
    return count;    
    }
//註冊
public int register(User user) throws SQLException{
    Connection conn=JDBCUtils.getConn();//數據庫鏈接語句
    String sql="insert into user(uname,pwd) values(?,?)";
    PreparedStatement pst=conn.prepareStatement(sql);//sql語句注入問題（1'or'1=1）
    pst.setString(1, user.getUname());//第一個問號，的值是user.getUname()，從1開始
    pst.setString(2, user.getPwd());
    int row = pst.executeUpdate();
    JDBCUtils.close(conn, pst);//釋放資源，
    return row;    
    }
}

package controller;

import domain.User;
import service.UserService;

public class UserController {
    //一、封裝前臺數據傳給後臺
    //二、接收後臺數據傳給前臺
    private UserService userService=new UserService();
    public int login(String username,String password){
        return userService.login(username, password);
    }
    //驗證用戶名是否存在
    public int checkUsername(String uname){
        return userService.checkUsername(uname);
    }
    //註冊用戶
    public String register(String uname,String pwd){
        //封裝前臺數據
        User user=new User ();
        user.setUname(uname);
        user.setPwd(pwd);
        return userService.register(user);
    }
}
    

package domain;

public class User {
private int uid;
private String uname;
private 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;
}
@Override
public String toString() {
    return "User [uid=" + uid + ", uname=" + uname + ", pwd=" + pwd + "]";
}

}

package dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import domain.Sort;
import tools.JDBCUtils;
public class SortDao {
    //新增分類
    public int addSort(String sname) throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="insert into sort(sname)values(?)";
        PreparedStatement pst=conn.prepareStatement(sql);
        pst.setString(1, sname);    
        int row = pst.executeUpdate();
        JDBCUtils.close(conn, pst);
        return row;    
    }
    //查詢全部分類
    public List<Sort>getall() throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="select * from sort";
        PreparedStatement pst=conn.prepareStatement(sql);
        ResultSet rs=pst.executeQuery();
        //處理結果集
        List<Sort>list=new ArrayList<Sort>();
        while(rs.next()){
            Sort sort=new Sort();
            sort.setSid(rs.getInt("sid"));
            sort.setSname(rs.getString("sname"));
            list.add(sort);
        }
        //釋放資源
        JDBCUtils.close(conn, pst, rs);
        return list;
    }
    //修改分類方法
    public int updateSort(int sid,String sname) throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="update sort set sname=? where sid=?";
        PreparedStatement pst=conn.prepareStatement(sql);
        pst.setString(1, sname);
        pst.setInt(2, sid);
        int row=pst.executeUpdate();
        JDBCUtils.close(conn, pst);
        return row;
    }
    //刪除分類
    public int deleteSort(int sid) throws SQLException{
        Connection conn=JDBCUtils.getConn();
        String sql="delete from sort where sid=?";
        PreparedStatement pst=conn.prepareStatement(sql);
        pst.setInt(1, sid);
        int row=pst.executeUpdate();
        JDBCUtils.close(conn, pst);
        return row;    
    }
}

package service;
import java.sql.SQLException;
import java.util.List;
import dao.SortDao;
import domain.Sort;
public class SortService {
    private SortDao sortDao=new SortDao();
    //新增分類
    public String addSort(String sname){
    int row=0;
    String mes="";
     try {
        row=sortDao.addSort(sname);
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
     if(row>0){
         mes="新增成功";
     }else{
         mes="新增失敗";
     }
     return mes;
    }
    public List<Sort> getall(){
        List<Sort> list=null;
        try {
            list=sortDao.getall();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return list;
    }
    public String updateSort(int sid,String sname){
        int row=0;
        String mes="";
        try {
            row=sortDao.updateSort(sid,sname);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        if(row>0){
            mes="修改爲功";
        }else{
            mes="修改失敗";
        }
        return mes;
    }
    //刪除
    public String deleteSort(int sid){
        int row=0;
        String  mes="";
        try {
        row=sortDao.deleteSort(sid);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        if(row>0){
            mes="刪除成功";
        }else{
            mes="刪除失敗";
        }
        return mes;
    }
    
}

package controller;
import java.util.List;
import domain.Sort;
import service.SortService;
public class SortController {
    private SortService sortService=new SortService();
    //新增
    public String addSort(String sname){
        return sortService.addSort(sname);
    }
    //查詢
    public List<Sort> getall(){
        return sortService.getall();
    }
    //修改分類
    public String updateSort(int sid,String sname){
        return sortService.updateSort(sid,sname);
    }
    //刪除分類
    public String deleteSort(int sid){
        return sortService.deleteSort(sid);
    }
}

package domain;

public class Sort {
    private int sid;
    private String sname;
    public int getSid() {
        return sid;
    }
    public void setSid(int sid) {
        this.sid = sid;
    }
    public String getSname() {
        return sname;
    }
    public void setSname(String sname) {
        this.sname = sname;
    }
    @Override
    public String toString() {
        return "Sort [sid=" + sid + ", sname=" + sname + "]";
    }
    
    
}

package test;
import view.MainView;
public class Demo {
    public static void main(String[] args) {
        new MainView().run();    
    }
}