java-DAO模式实现数据库增,删,改,查和传统模式实现数据库增,删,改,查对比-JDBC

传统模式和DAO模式下对数据库进行增删改查对比操作

传统模式：

首先创建数据库表结构:（数据库以mysql为例，下同，项目使用数据库可改）



传统模式java代码：

package com.hkd.myschool;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Scanner;

public class Phone {

/**
* @param args
*/
static String[] arr = {"添加数据","查询数据","删除数据","退出操作"};
static Scanner sc = new Scanner(System.in);
//入口main函数
public static void main(String[] args) {
// 添加驱动
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//循环操作
cc:do{//添加循环标签cc
System.out.println("请选择您要进行的操作：");
for(int i=0;i<arr.length;i++){
System.out.println((i+1)+"."+arr[i]);
}
int choose = sc.nextInt();
switch(choose){
case 1:
System.out.println("请输入id：");
int id = sc.nextInt();
System.out.println("请输入姓名：");
String name = sc.next();
System.out.println("请输入手机号：");
String tel = sc.next();
System.out.println("请输入机号类型：");
String type = sc.next();
add(id,name,tel,type);
break;
case 2:
show();
break;
case 3:
System.out.println("请输入该人员姓名：");
String inputname = sc.next();
delete(inputname);
break;
case 4:
System.out.println("谢谢使用！");
break cc;//通过标签跳出do while循环
default:
break cc;//通过标签跳出do while循环
}
}while(true);

//测试使用
/*try {
Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/phone", "root", "root");
//创建查询对象
Statement st = conn.createStatement();
String sql = "insert into phoneinfo values(null,'lcn','18437963795','移动')";

int a =st.executeUpdate(sql);

st.close();
conn.close();

if(a>0){
System.out.println("成功");
}else{
System.out.println("失败");
}

} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}*/
}
//--------------------------------------------------功能模块------------------------------------------------------
//添加方法
public static void add(int id,String name,String tel,String type){

try {
Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/phone", "root", "root");
//创建查询对象
Statement st = conn.createStatement();
String sql = "insert into phoneinfo values("+id+",'"+name+"','"+tel+"','"+type+"')";//添加数据，注意传参时的转换

int a =st.executeUpdate(sql);
st.close();
conn.close();
if(a>0){
System.out.println("添加成功");
}else{
System.out.println("添加失败");
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

//删除方法
public static void delete(String inputname){
try {
Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/phone", "root", "root");
//创建查询对象
Statement st = conn.createStatement();
String sql = "delete from phoneinfo where name='"+inputname+"'";
st.executeUpdate(sql);//更新数据

st.close();
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

//查询方法
public static void show(){
try {
Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/phone", "root", "root");
//创建查询对象
Statement st = conn.createStatement();
String sql = "select * from phoneinfo";

ResultSet rs = st.executeQuery(sql);
while(rs.next()){
System.out.println("编号："+rs.getInt("id"));
System.out.println("姓名："+rs.getString("name"));
System.out.println("手机号："+rs.getString("tel"));
System.out.println("机号类型："+rs.getString("type"));
System.out.println();
}

st.close();
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//----------------------------------------------------------------------------------------------------------------
}

数据库操作界面图示：



DAO模式下对数据库进行增删改查：

首先创建数据库表结构:



java代码：

架构图：



BaseDao类：

package com.hkd.myschool.dao;

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

import java.sql.PreparedStatement;

public class BaseDao {
String DBUser="root";//用户名
String DBPwd="root";//密码
String DBHost="127.0.0.1";//服务器地址
String DBName="phone1";//数据库名称
int Port = 3306;//端口
int DBType = 1;//数据库类型

Connection conn;//连接对象
PreparedStatement ps;//查询对象
ResultSet rs;//结果集

public void open(){
try {
if(DBType==1){
Class.forName("com.mysql.jdbc.Driver");
conn=DriverManager.getConnection("jdbc:mysql://"+DBHost+":"+Port+"/"+DBName, DBUser, DBPwd);
}else if(DBType==2){
Class.forName("com.microsoft.sqlserver.sqlserverDriver");
conn=DriverManager.getConnection("jdbc:sqlserver://"+DBHost+":"+Port+";database="+DBName, DBUser, DBPwd);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void close(){
try {
if(rs!=null) rs.close();
ps.close();
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/**
*
* @param sql
* @param parm
* @return
*/
public int executeUpdate(String sql,Object[] parm){
open();
int a=0;
try{
ps= conn.prepareStatement(sql);
if(parm!=null){
for(int i=0;i<parm.length;i++){
ps.setObject(i+1, parm[i]);
}
}
a=ps.executeUpdate();
}catch(Exception e){
e.printStackTrace();
}
close();
return a;
}
public ResultSet exectueQuery(String sql,Object[] parm)
{
open();

try{
ps= conn.prepareStatement(sql);
if(parm!=null){
for(int i=0;i<parm.length;i++){
ps.setObject(i+1, parm[i]);
}
}
rs=ps.executeQuery();
}catch(Exception e){
e.printStackTrace();
}

return rs;

}
}

StudentDao类：

package com.hkd.myschool.dao;

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

import com.hkd.myschool.entiy.Student;

public class StudentDao extends BaseDao{
public int add(Student stu){
String sql = "insert into student values(null,?,?,?)";
Object[] parm={stu.getStudentName(),stu.getStudentAge(),stu.getStudentTel()};

int a = executeUpdate(sql, parm);
return a;

}
public int delete(int studentNo){
String sql = "delete from student where studentNo=?";
Object[] parm={studentNo};
int a = executeUpdate(sql, parm);

return a;
}

public int update(Student stu){
String sql = "update student set studentName=? , studentAge=? , studentTel=? where studentNo=?";
Object[] parm={stu.getStudentName(),stu.getStudentAge(),stu.getStudentTel(),stu.getStudentNo()};
int a = executeUpdate(sql, parm);

return a;
}
public List<Student> getALL(){
String sql = "select * from student";
rs=exectueQuery(sql, null);
List<Student> list = new ArrayList<Student>();
try {
while(rs.next()){
Student s = new Student();
s.setStudentNo(rs.getInt("studentNo"));
s.setStudentName(rs.getString("studentName"));
s.setStudentAge(rs.getInt("studentAge"));
s.setStudentTel(rs.getInt("studentTel"));
list.add(s);
}
close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return list;

}
}

Student类：

package com.hkd.myschool.entiy;

public class Student {
private int studentNo;
private String studentName;
private int studentAge;
private int studentTel;
public int getStudentNo() {
return studentNo;
}
public void setStudentNo(int studentNo) {
this.studentNo = studentNo;
}
public String getStudentName() {
return studentName;
}
public void setStudentName(String studentName) {
this.studentName = studentName;
}
public int getStudentAge() {
return studentAge;
}
public void setStudentAge(int studentAge) {
this.studentAge = studentAge;
}
public int getStudentTel() {
return studentTel;
}
public void setStudentTel(int studentTel) {
this.studentTel = studentTel;
}

}

StudentBiz类：

package com.hkd.myschool.entiy;

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

import com.hkd.myschool.dao.StudentDao;

public class StudentBiz {
Student stu = new Student();
StudentDao sd = new StudentDao();
Scanner sc = new Scanner(System.in);
public void add(){
System.out.println("请输入姓名：");
stu.setStudentName(sc.next());
System.out.println("请输入年龄：");
stu.setStudentAge(sc.nextInt());
System.out.println("请输入电话：");
stu.setStudentTel(sc.nextInt());
int a=sd.add(stu);
if(a>0)System.out.println("成功");
else System.out.println("失败");
}
public void del(){
System.out.println("请输入编号：");
int a=sd.delete(sc.nextInt());
if(a>0)System.out.println("成功");
else System.out.println("失败");
}
public void update(){
System.out.println("请输入要修改的编号：");
stu.setStudentNo(sc.nextInt());
System.out.println("请输入要修改的姓名：");
stu.setStudentName(sc.next());
System.out.println("请输入要修改的年龄：");
stu.setStudentAge(sc.nextInt())
bbcc
;
System.out.println("请输入要修改的电话：");
stu.setStudentTel(sc.nextInt());
int a=sd.update(stu);
if(a>0)System.out.println("修改成功");
else System.out.println("修改失败");
}
public void show(){
List<Student> list=sd.getALL();
for(Student s:list){
System.out.println(s.getStudentNo()+"\t"+s.getStudentName()+"\t"+s.getStudentAge()+"\t"+s.getStudentTel());
}
}

}

Main入口类：

package com.hkd.myschool.entiy;

import java.util.Scanner;

public class Main {

/**
* @param args
*/
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
StudentBiz sb = new StudentBiz();
System.out.println("*********************");
System.out.println("***     添加学生            ***");
System.out.println("***     删除学生            ***");
System.out.println("***     修改学生            ***");
System.out.println("***     查询学生            ***");
System.out.println("*********************");

System.out.println("请输入您的选择：");
int a = sc.nextInt();
switch(a){
case 1:
sb.add();
break;
case 2:
sb.del();
break;
case 3:
sb.update();
break;
case 4:
sb.show();
break;

}

}

}

输出图示：

先显示一下数据库里的人员信息；键盘输入4



进行添加操作：键盘输入1



查询添加的数据：键盘输入4


数据添加成功！

删除数据操作：键盘输入2

执行删除编号为2的学生数据



再次查询表中的数据：键盘输入4



编号为2的学生信息已经删除

修改数据自行同理，不做演示！

数据库操作界面图示：