目录

一、JDBC基本操作步骤

二、JDBC代码

三、lombok插件的安装与使用

1、lombok插件的安装

2、lombok常用注解

Data

Getter

Setter

ToString

AllArgsConstructor

NoArgsConstructor

3、lombok的使用

四、JDBC代码分析

一、JDBC基本操作步骤

1、导包mysql-connector-java

2、注册驱动

3、获取连接

4、获取执行sql语句的对象

5、编写sql，发送sql

6、处理结果集

7、释放资源

二、JDBC代码

CREATE DATABASE mybatisdatabase;
USE mybatisdatabase;
CREATE TABLE IF NOT EXISTS `admin`(
`uid` INT PRIMARY KEY AUTO_INCREMENT,
`username` VARCHAR(20),
`upassword` VARCHAR(20) NOT NULL,
`phone` VARCHAR(11) UNIQUE NOT NULL,
`address` VARCHAR(10) NOT NULL
);INSERT INTO `admin`(`username`,`upassword`,`phone`,`address`) VALUES
('张三','123456','18145772645','安徽合肥包河区'),
('李四','456789','15695688968','安徽合肥高新区');

import lombok.Data;@Data
public class Admin {private int uid;private String username;private String upassword;private String address;
}

package com.mybatis;import java.sql.*;
import java.util.ArrayList;public class App {public static void main(String[] args) {Connection connection = null;PreparedStatement preparedStatement = null;ResultSet resultSet = null;try {//注册驱动Driver driver = new com.mysql.jdbc.Driver();DriverManager.registerDriver(driver);//获取连接//serverTimezone：设置时区--->UTC：标准时间//useSSL：是否使用更安全连接//characterEncoding：设置编码格式String url = "jdbc:mysql:///mybatisdatabase?serverTimezone=UTC&useSSL=false&characterEncoding=UTF-8";String user = "root";String password = "123456";connection = DriverManager.getConnection(url,user,password);System.out.println("connection = " + connection);//编辑sql语句String sql = "select * from admin;";//获取执行sql语句的对象preparedStatement = connection.prepareStatement(sql);//获取结果集resultSet = preparedStatement.executeQuery();//处理结果集ArrayList<Admin> arrayList = new ArrayList<Admin>();while(resultSet.next()){int uid = resultSet.getInt("uid");String username = resultSet.getString(2);String upassword = resultSet.getString("upassword");String address = resultSet.getString(4);Admin admin = new Admin();admin.setUid(uid);admin.setUsername(username);admin.setUpassword(upassword);admin.setAddress(address);arrayList.add(admin);}System.out.println("arrayList = " + arrayList);} catch (SQLException e) {e.printStackTrace();}finally{//释放资源try {if (connection != null){connection.close();}} catch (SQLException e) {e.printStackTrace();}try {if (preparedStatement != null){preparedStatement.close();}} catch (SQLException e) {e.printStackTrace();}try {if (resultSet != null){resultSet.close();}} catch (SQLException e) {e.printStackTrace();}}}
}

三、lombok插件的安装与使用

使用lombok插件可自动生成实体类的构造方法、get()/set()方法、toString()方法、equals()方法等 

1、lombok插件的安装

file--->Settings...--->Plugins--->搜索lombok--->Installed

2、lombok常用注解

Data

整合了Getter、Setter、ToString、EqualsAndHashCode、RequiredArgsConstructor注解。

Getter

快速构建Getter方法。

Setter

快速构建Setter方法。

ToString

快速将当前对象转换成字符串类型，便于log。

AllArgsConstructor

全参构造。

NoArgsConstructor

无参构造。

<dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.24</version>
</dependency>

import lombok.Data;@Data
public class Admin {private int uid;private String username;private String upassword;private String address;
}