2021.5.10

今日学习内容：

	第一天	第二天	第三天	第四天	第五天
所花时间（小时）	5
代码量（行）	500
博客量（篇）	1
了解到的知识点	web系统

重新写一个简单的学生管理系统，连接mysql数据库，利用html+css+sqlserver+eclipse:

首先编写java类：

Dao.java

package dao;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import DBUtil.DBUtil;
import entity.Student;

public class Dao {

    public Dao() {
        // TODO Auto-generated constructor stub
    }
    
    public static List<Student> getAllStudents(){            //获取学生列表
        List<Student> list=new ArrayList<Student>();
        Connection con=DBUtil.getConnection();
        ResultSet rs=null;
        String sql="select * from student";
        try{
            Statement statement=con.createStatement();    
            rs=statement.executeQuery(sql);
            while(rs.next()) {
                Student student=new Student();
                student.setId(rs.getInt("id"));
                student.setAddress(rs.getString("address"));
                student.setBirthday(rs.getString("birthday"));
                student.setName(rs.getString("name"));
                student.setSex(rs.getString("sex"));
                list.add(student);
            }
            DBUtil.closeDB(con, statement, rs);
        }catch(Exception e){
            e.printStackTrace();
        }
        return list;
    }
    
    public static void addStudent(Student student) {            //添加学生
        String sql="insert into student(name,sex,birthday,address) "
                + "values('"+student.getName()+"','"+student.getSex()+"','"+student.getBirthday()+"','"+student.getAddress()+"')";
        Connection connection=DBUtil.getConnection();
        try {
            Statement statement=connection.createStatement();
            statement.executeUpdate(sql);
            DBUtil.closeDB(connection, statement, null);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    public static void deleteStudent(int id) {    //删除学生
        String sql="delete from student where id="+id;
        Connection connection=DBUtil.getConnection();
        try {
            Statement statement=connection.createStatement();
            statement.executeUpdate(sql);
            DBUtil.closeDB(connection, statement, null);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    public static void updateStudent(Student student) {        //修改学生
        String sql="update student set name='"+student.getName()+"',sex='"+student.getSex()+"',"
                + "birthday='"+student.getBirthday()+"',address='"+student.getAddress()+"' "
                + "where id="+student.getId();
        Connection connection=DBUtil.getConnection();
        try {
            Statement statement=connection.createStatement();
            statement.executeUpdate(sql);
            DBUtil.closeDB(connection, statement, null);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    public static Student getStudent(int id) {
        Student student=new Student();
        Connection connection=DBUtil.getConnection();
        ResultSet rs=null;
        String sql="select * from student where id="+id;
        try {
            Statement statement=connection.createStatement();
            rs=statement.executeQuery(sql);
            if(rs.next()) {
                student.setId(rs.getInt("id"));
                student.setAddress(rs.getString("address"));
                student.setBirthday(rs.getString("birthday"));
                student.setName(rs.getString("name"));
                student.setSex(rs.getString("sex"));
            }
            DBUtil.closeDB(connection, statement, rs);
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return student;
    }

}

DBUtil.java

package DBUtil;


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

public class DBUtil {

    private static String url = "jdbc:sqlserver://127.0.0.1:54595;DatabaseName=stu";
    private static String username="rong";
    private static String password="123456";
    
    
    public static Connection getConnection() {
        Connection con=null;
        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            con = DriverManager.getConnection(url,username,password);
            System.out.println("连接成功");
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("连接失败");
        }
        return con;
    }
    
    public static void closeDB(Connection connection,Statement statement,ResultSet resultSet) {
        if(connection!=null)
            try {
                connection.close();
            } catch (SQLException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        if(statement!=null)
            try {
                statement.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        if(resultSet!=null)
            try {
                resultSet.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
    }

    
    public DBUtil() {
        // TODO Auto-generated constructor stub
    }
    
    
    
    public static void main(String[] args) throws SQLException {
        Connection connection=getConnection();
    
        closeDB(connection, null, null);
    }

}

Student.java

package entity;

public class Student {

    private int id;
    private String name;
    private String sex;
    private String birthday;
    private String address;
    
    public Student() {
        // TODO Auto-generated constructor stub
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getBirthday() {
        return birthday;
    }

    public void setBirthday(String birthday) {
        this.birthday = birthday;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

}