第六个JSP作业-jdbc

创建数据库

1.创建javaBean的封装数据：User

package com.test.jdbc;
import java.util.Date;
public class User{
        private int id;
        private String username;
        private String password;
        private String email;
        private Date birthDay;
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getUsername() {
            return username;
        }
        public void setUsername(String username) {
            this.username = username;
        }
        public String getPassword() {
            return password;
        }
        public void setPassword(String password) {
            this.password = password;
        }
        public String getEmail() {
            return email;
        }
        public void setEmail(String email) {
            this.email = email;
        }
        public Date getBirthDay() {
            return birthDay;
        }
        public void setBirthDay(Date birthDay) {
            this.birthDay = birthDay;
        }
}

2.创建工具类：JDBCUtils

package com.test.jdbc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
 
public class JDBCUtils {
    public static Connection getCon() throws Exception{
        Class.forName("com.mysql.jdbc.Driver");
        Connection con =DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
       return con;
    }
    public static void realse (ResultSet rs,Statement stmt, Connection con){
         
        if(rs!=null){     
            try {
                rs.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(stmt!=null){
             try {
                stmt.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        if(con!=null){
            try {
                con.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
 
}

3.创建一个Dao类：UsersDao

package com.test.jdbc;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
 
public class UsersDao {
    public boolean insert(User user1){
        Connection con=null;
        Statement stmt=null;
        try{
            con=JDBCUtils.getCon();
            stmt = con.createStatement();
            java.util.Date birthday=user1.getBirthDay();
            String sqlBirthDay=String.format("%tF", birthday);
            String sql="insert into user(id,name,password,email,birthday)"+"values('"
            +user1.getId()+"','"
            +user1.getUsername()+"','"
            +user1.getPassword()+"','"
            +user1.getEmail()+"','"
            +sqlBirthDay+"'"
            +")";
            int row=stmt.executeUpdate(sql);   
            if(row>0){
                return true;
            }
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            JDBCUtils.realse(null, stmt, con);
        }
         
        return false;
    }
    public List<User> findAllUser(){
        Connection con =null;
        Statement stmt =null;
        ResultSet  rs  =null;
        try{
            con=JDBCUtils.getCon();
            stmt=con.createStatement();
            String sql="select * from user";
             rs=stmt.executeQuery(sql);
             List<User> list=new ArrayList<User>();
             while(rs.next()){
                 User user1=new User();
                 user1.setId(rs.getInt("id"));
                 user1.setUsername(rs.getString("name"));
                 user1.setPassword(rs.getString("password"));
                 user1.setEmail(rs.getString("email"));
                 java.sql.Date birthday=rs.getDate("birthday");
                 user1.setBirthDay(birthday);
                 list.add(user1);                  
             }
              
             return list;
              
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            JDBCUtils.realse(rs, stmt, con);
        }
         
    }
    public User findUserById(int id){
        Connection con =null;
        PreparedStatement stmt=null;
        ResultSet   rs =null;
        try{
            con=JDBCUtils.getCon();
            String sql="select * from user where id=?";
            stmt=con.prepareStatement(sql);
            stmt.setInt(1, id);
            rs=stmt.executeQuery();             
             if(rs.next()){
                 User user1=new User();
                 user1.setId(rs.getInt("id"));
                 user1.setUsername(rs.getString("name"));
                 user1.setPassword(rs.getString("password"));
                 user1.setEmail(rs.getString("email"));
                 java.sql.Date birthday=rs.getDate("birthday");
                 user1.setBirthDay(birthday);           
                 return user1;
             }  
             
              
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            JDBCUtils.realse(rs, stmt, con);
        }
        return null;
         
    }
    public boolean update(User user1){
         
        Connection con=null;
        PreparedStatement stmt=null;
        try{            
            con=JDBCUtils.getCon();
            String sql="update user set name=?,password=? where id=?";
            stmt = con.prepareStatement(sql);          
            stmt.setString(1, user1.getUsername());
            stmt.setString(2, user1.getPassword());
            stmt.setInt(3, user1.getId());
             
            int row=stmt.executeUpdate();  
            if(row>0){
                return true;
            }
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            JDBCUtils.realse(null, stmt, con);
        }
         
        return false;
    }        
    public boolean delete (int id){
        Connection con=null;
        PreparedStatement stmt=null;
        try{
            con=JDBCUtils.getCon();
            String sql="delete from user where id=?";
            stmt = con.prepareStatement(sql);
            stmt.setInt(1,id);
            int row=stmt.executeUpdate();  
            if(row>0){
                return true;
            }
        }catch(Exception e){
            throw new RuntimeException(e);
        }finally{
            JDBCUtils.realse(null, stmt, con);
        }
         
        return false;
    }
}

4.创建的测试类

1.测试添加方法类：JdbcInsertTest

package com.test.jdbc;
import java.util.Date;

public class JdbcInsertTest {
     
    public static void main(String[] args) {
        UsersDao dao=new UsersDao();
        User user1=new User();
        user1.setId(4);
        user1.setUsername("mkx");
        user1.setPassword("123321");
        user1.setEmail("123321@qq.com");
        user1.setBirthDay(new Date());
        boolean flag=dao.insert(user1);
 
    }
 
}

2.测试查询所有的方法类：FindAllUserTest

package com.test.jdbc;
import java.util.List;

public class FindAllUserTest {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        UsersDao dao = new UsersDao();
        List<User> list=dao.findAllUser();    
        System.out.println(list.size());
    }
 

3.测试查询一个对象的类：FindUserByIdTest

package com.test.jdbc;
public class FindUserByIdTest {
	 
    
    public static void main(String[] args) {
        UsersDao dao = new UsersDao();
        User u=dao.findUserById(4);
        System.out.println(u.getUsername());
    }
 
}

4.测试修改方法的类：UpdateUserTest

package com.test.jdbc;
public class UpdateUserTest {
	 
    
    public static void main(String[] args) {
        UsersDao dao=new UsersDao();
        User u=new User();
        u.setId(4);
        u.setUsername("sq");
        u.setPassword("123345");
        boolean flag=dao.update(u);
        System.out.println(flag);
    }
 
}

5.测试删除方法的类：DeleteUserTest

package com.test.jdbc;
public class DeleteUserTest {
	 
    
    public static void main(String[] args) {
        UsersDao dao=new UsersDao();
        boolean flag=dao.delete(1);
        System.out.println(flag);
    }
 
}