【Sql Server】eclipse 连接sql server实现登录注册功能

package app;

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

import game.GameFrame;

//程序入口
//改名快捷键shift +f6
public class GameMain {
	static Scanner sc = new Scanner(System.in);
	static String name;
	static String passward;

	public static void main(String[] args) {

		System.out.println("***********欢迎来到坦克大战***********");
		login();
		new GameFrame();
	}

	public static void login() {
		System.out.println("**********请选择你的操作：**********");
		System.out.println("1.登录  2.注册");
		int n = sc.nextInt();
		if (n == 1) {
			System.out.println("请输入昵称：");
			name = sc.next();
			System.out.println("请输入密码：");
			passward = sc.next();
			String sql = "select * from Users where admin='" + name + "'and password='" + passward + "'";
			if (flogin(sql)) {
				System.out.println("**********登录成功！**********");
			} else {
				System.out.println("**********用户不存在！**********");
				login();
			}
		} else if (n == 2) {
			String str;
			System.out.println("请输入昵称：");
			name = sc.next();
			System.out.println("请输入密码：");
			passward = sc.next();
			System.out.println("确认密码：");
			str = sc.next();
			while (!passward.equals(str)) {
				System.out.println("**********密码输入不一致，请重新输入**********");
				System.out.println("请输入密码：");
				passward = sc.next();
				System.out.println("确认密码：");
				str = sc.next();
			}
			if (register(name, passward)) {
				System.out.println("**********注册成功！**********");
			} else {
				System.out.println("**********注册失败！请重新注册**********");
			}
			login();

		} else {
			System.out.println("暂无该操作");
			login();
		}
	}

	// 数据库连接
	static Connection con;

	public static Connection getconnection() {
		String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
		String dbURL = "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=TanKe";// TanKe为数据库名
		String userName = "sa";// 你的数据库用户名
		String userPwd = "20020319";// 你的密码
		try {
			Class.forName(driverName);
			System.out.println("加载驱动成功！");
		} catch (Exception e) {
			e.printStackTrace();
			System.out.println("加载驱动失败！");
		}
		try {
			con = DriverManager.getConnection(dbURL, userName, userPwd);
			Statement statement = null;
			ResultSet rs = null;
			System.out.println("连接数据库成功！");
		} catch (Exception e) {
			e.printStackTrace();
			System.out.print("SQL Server连接失败！");
		}
		return con;
	}

	// 登录方法
	public static boolean flogin(String sql) {
		Connection connection = getconnection();

		try {
			Statement statement = (Statement) connection.createStatement();
			ResultSet rs = statement.executeQuery(sql);
			if (rs.next()) {
				//打印用户
//				while (rs.next()) {
//					int id = rs.getInt("ID");
//					String userName = rs.getString("admin");
//					int userage = rs.getInt("password");
//					System.out.print(id + "  ");
//					System.out.print(userName + "  ");
//					System.out.println(userage);
//				}
				statement.close();
				return true;
			} else {
				return false;
			}

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return false;
		}

	}

	// 注册方法
	public static boolean register(String name, String passward) {
		Connection connection = getconnection();
		String sql = "select * from Users where admin='" + name + "'";
		try {
			Statement statement = (Statement) connection.createStatement();
			ResultSet rs = statement.executeQuery(sql);
			if (rs.next()) {
				System.out.println("用户名已存在！");
				return false;
			} else {
				String updateSql = "insert into Users values(?,?);";
				PreparedStatement presta = connection.prepareStatement(updateSql);
				presta.setString(1, name);
				presta.setString(2, passward);
				presta.executeUpdate();
				statement.close();
				presta.close();
				return true;
			}

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return false;
		}
	}

	// 释放数据库
	public void deleteConnection() throws SQLException {
		if (con != null) {
			con.close();
		}
		con = null;
	}

}