第七周作业

1.创建数据库

create database jdbc1;

use jdbc1;

create table user(id int primary key auto_increment,
                                name varchar(30),
                                password varchar(30),
                                email  varchar(100),
                                birthday Date);
insert into user(name,password,email,birthday) values('litao','1007','5288471512@qq.com','1998-03-14');
insert into user(name,password,email,birthday) values('tianyihui','6384','528765456@qq.com','1998-02-14');
insert into user(name,password,email,birthday) values('minkexin','9872','853308091@qq.com','1999-01-26');

　　

2.创建JavaBean的封装数据：users

package cn.itcast.jdbc.example;

import java.util.Date;

public class Users {
	//封装
		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;
		}
}

　　3.创建工具类：JDBCUtils

package cn.itcast.jdbc.example;

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

public class JDBCUtils {
     //获取连接对象的方法
	public static Connection getCon() throws Exception{
		//1.注册和加载驱动
		Class.forName("com.mysql.jdbc.Driver");
		//2.获取驱动
	   Connection con =DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbc1", "root", "root");
	   return con;
	}
	//关闭连接，释放资源
	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();
			}
		}
	}

}

　4.创建一个Dao类：UsersDao

package cn.itcast.jdbc.example;

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 {

	/**
	 * 完成对数据库的crud操作
	 * @param args
	 */
	public boolean insert(Users user1){
		Connection con=null;
		Statement stmt=null;
		try{
			//1.获取连接对象
			con=JDBCUtils.getCon();
			//2.获取执行sql语句的对象
		    stmt = con.createStatement();
			//3.执行sql
			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){
				//插入成功
				return true;
			}
		}catch(Exception e){
			throw new RuntimeException(e);
		}finally{
			JDBCUtils.realse(null, stmt, con);
		}
		
		return false;
	}
	
	//2.提供查询的方法
	public List<Users> findAllUser(){
		Connection con =null;
		Statement stmt =null;
		ResultSet  rs  =null;
		try{
			//1.获取连接对象
			con=JDBCUtils.getCon();
			//2.获取执行sql语句的对象
			stmt=con.createStatement();
			//3.执行sql
			String sql="select * from user";
			 rs=stmt.executeQuery(sql);
			 //4.遍历rs
			 List<Users> list=new ArrayList<Users>();
			 while(rs.next()){
				 //一行数据对应一个对象
				 Users user1=new Users();
				 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);
				 //把对象添加到集合中
				 list.add(user1);				 
				 
			 }
			 
			 return list;
			 
		}catch(Exception e){
			throw new RuntimeException(e);
		}finally{
			JDBCUtils.realse(rs, stmt, con);
		}
		
	}
	
	//3.根据id，来查询记录
	public Users findUserById(int id){
		Connection con =null;
		PreparedStatement stmt=null;
		ResultSet   rs =null;
		try{
			//1.获取连接对象
			con=JDBCUtils.getCon();
			//2.获取执行sql语句的对象
			String sql="select * from user where id=?";
			stmt=con.prepareStatement(sql);
			//3.执行sql,给占位符赋值
			stmt.setInt(1, id);
			rs=stmt.executeQuery();
			 //4.遍历rs
			 if(rs.next()){
				 //一行数据对应一个对象
				 Users user1=new Users();
				 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;
		
	}
	
	//4.提供一个修改方法，根据id修改记录
	public boolean update(Users user1){
		
		Connection con=null;
		PreparedStatement stmt=null;
		try{
			//1.获取连接对象
			con=JDBCUtils.getCon();
			//2.获取执行sql语句的对象
			String sql="update user set name=?,password=? where id=?";
		    stmt = con.prepareStatement(sql);
			//3.执行sql,给占位符赋值
			stmt.setString(1, user1.getUsername());
			stmt.setString(2, user1.getPassword());
			stmt.setInt(3, user1.getId());
			
			int row=stmt.executeUpdate();	
			if(row>0){
				//插入成功
				return true;
			}
		}catch(Exception e){
			throw new RuntimeException(e);
		}finally{
			JDBCUtils.realse(null, stmt, con);
		}
		
		return false;
	}
	
	//5.删除方法
	public boolean delete (int id){
		Connection con=null;
		PreparedStatement stmt=null;
		try{
			//1.获取连接对象
			con=JDBCUtils.getCon();
			//2.获取执行sql语句的对象
			String sql="delete from user where id=?";
		    stmt = con.prepareStatement(sql);
			//3.执行sql,给占位符赋值
			
			stmt.setInt(1,id);
			
			int row=stmt.executeUpdate();	
			if(row>0){
				//插入成功
				return true;
			}
		}catch(Exception e){
			throw new RuntimeException(e);
		}finally{
			JDBCUtils.realse(null, stmt, con);
		}
		
		return false;
	}
}

　　5.创建的测试类

         1）.添加方法类：jdbcInsertTest

package cn.itcast.jdbc.example;

import java.util.Date;

public class JdbcInsertTest {

	
	public static void main(String[] args) {
		
		//插入数据
		UsersDao dao=new UsersDao();
		Users user1=new Users();
		user1.setId(4);
		user1.setUsername("sui");
		user1.setPassword("8437");
		user1.setEmail("52884712@qq.com");
		user1.setBirthDay(new Date());
		boolean flag=dao.insert(user1);

	}

}

　　

2）.查询所有的方法类：FindAllUserTest

package cn.itcast.jdbc.example;

import java.util.List;

public class FindAllUserTest {

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

}

3).查询类：FindUserByIdTest

package cn.itcast.jdbc.example;

public class FindUserByIdTest {

	
	public static void main(String[] args) {
		UsersDao dao = new UsersDao();
		Users u=dao.findUserById(4);
		System.out.println(u.getUsername());
	}

}

　

4)修改方法：UpdateUserTest

package cn.itcast.jdbc.example;

public class UpdateUserTest {

	
	public static void main(String[] args) {
		UsersDao dao=new UsersDao();
        Users u=new Users();
        u.setId(4);
        u.setUsername("suixiaoyi");
        u.setPassword("4829");
        boolean flag=dao.update(u);
        System.out.println(flag);
	}

}

　　

5).删除方法类：DeleteUserTest

package cn.itcast.jdbc.example;

public class DeleteUserTest {

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

}