学生信息管理系统1

package top.gaojc;

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

public class DBUtil {
  
  // 1.加载驱动程序(项目中添加驱动包)
  static{
    try {
      Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
    } catch (ClassNotFoundException e) {
      e.printStackTrace();
    }
  }
  
  // 2.使用DriverManager连接数据库
  public static Connection getConn(){
    Connection conn = null;
    try {
      // ("jdbc:运行环境://localhost:端口号;databaseName=数据库名称","SQL账号","SQL密码")
      conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=school", "sa", "1");
    } catch (SQLException e) {
      e.printStackTrace();
    }
    return conn;
  }
  
  // 7.关闭资源
  public static void Close(Connection conn,PreparedStatement ps,ResultSet rs){
    try {
      if(conn != null)
      conn.close();
    } catch (SQLException e) {
      e.printStackTrace();
    }
    
    try {
      if(ps != null)
      ps.close();
    } catch (SQLException e) {
      e.printStackTrace();
    }
    
    try {
      if(rs != null)
      rs.close();
    } catch (SQLException e) {
      e.printStackTrace();
    }
  }
}

package top.gaojc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Scanner;

public class Insert {
  
  public static void main(String[] args) throws SQLException {
    
    // 从控制台输入我想添加的数据
    System.out.println("请输入需要添加的数据：");
    Scanner scan = new Scanner(System.in);
    System.out.print("姓名：");
    String name = scan.nextLine();
    System.out.print("性别：");
    String sex = scan.nextLine();
    System.out.print("年龄：");
    int age = scan.nextInt();
    
    // 1 2  调用DBUtil
    Connection conn = DBUtil.getConn();
    
    // 3.准备一个sql语句
    String sql = "insert into student(name,sex,age) values (?,?,?)";
    
    // 4.准备一个和数据库打交道的
    PreparedStatement ps = conn.prepareStatement(sql);
    
    // 给sql语句中的?赋值
    ps.setString(1, name);
    ps.setString(2, sex);
    ps.setInt(3, age);
    
    // 5.结果赋值
    int count = ps.executeUpdate();
    
    // 6.输出
    if (count > 0) {
      System.out.println("添加成功！");
    }else{
      System.out.println("添加失败！");
    }
    
    // 7.调用DBUtil
    DBUtil.Close(conn, ps, null);
  }
}

package top.gaojc;

package top.gaojc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Scanner;

public class Delete {

  public static void main(String[] args) throws SQLException {

    // 从控制台输入我想删除的数据id
    System.out.print("请输入需要删除的数据id：");
    Scanner scan = new Scanner(System.in);
    int id = scan.nextInt();

    // 1 2  调用DBUtil
    Connection conn = DBUtil.getConn();

    // 3.准备一个sql语句
    String sql = "delete from student where id = ?";

    // 4.准备一个和数据库打交道的
    PreparedStatement ps = conn.prepareStatement(sql);

    // 给sql语句中的?赋值
    ps.setInt(1, id);

    // 5.结果赋值
    int count = ps.executeUpdate();

    // 6.输出
    if (count > 0) {
      System.out.println("删除成功！");
    } else {
      System.out.println("删除失败！");
    }

    // 7.调用DBUtil
    DBUtil.Close(conn, ps, null);
  }
}