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通过JDBC连接数据库实现一个简单的登录操作

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

import 工具类.javabean;

public class loginin {
public static javabean first=new javabean ();
public static Scanner cin=new Scanner(System.in);
public static void main(String[] args) throws ClassNotFoundException, SQLException {
System.out.println("请输入账号：");
String user=cin.nextLine();
System.out.println("请输入密码");
String passward = cin.nextLine();
first.setUser(user);
first.setPassward(passward);
if(jdbc(first.getUser(), first.getPassward()))
System.out.println("登陆成功");
else
System.out.println("用户名或密码错误");
}
public static Boolean jdbc(String user,String passward) throws ClassNotFoundException, SQLException
{
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
//1. 导入驱动jar包
//2.注册驱动
Class.forName("com.mysql.jdbc.Driver");
//3.获取数据库连接对象
// Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/a", "root", "root");
//4.定义sql语句
// String sql = "update account set balance = 2000 where id = 1";
String sql = "select *from test";
//5.获取执行sql的对象 Statement
stmt = conn.createStatement();
//6.执行sql
// int count = stmt.executeUpdate(sql);
rs = stmt.executeQuery(sql);
rs.next();
while(true){
//7.处理结果
String User=rs.getString("user");
String Passward=rs.getString("passward");
System.out.println(User+" "+Passward);
if(first.getUser().equals(User)&&first.getPassward().equals(Passward))
return true;
if(rs.next()==false)
break;
}
return false;
}
}

 

public class javabean {
private String user;
private String passward;
public String getUser() {
return user;
}
public void setUser(String user) {
this.user = user;
}
public String getPassward() {
return passward;
}
public void setPassward(String passward) {
this.passward = passward;
}
}