mysql8.0集成到项目(mybatis-plus)

mysql 8之前配置:

private static String url = "jdbc:mysql://localhost:3306/mydb";
    private static String driver = "com.mysql.jdbc.Driver";
    private static String username = "root";
    private static String passworld = "你的密码";

mysql8之后要更改：

1 jar要使用 8之后

报错:com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.13</version>
		</dependency>

其他版本jar见：https://mvnrepository.com/artifact/mysql/mysql-connector-java

2 高版本的 Mysql 中，引入了 SSL 安全认证，需要拥有一定的安全证书去连接数据库.

报错WARN: Establishing SSL connection without ...

设置忽略useSSL=false。

private static String url = "jdbc:mysql://localhost:3306/mydb?useSSL=false"

3 更换驱动

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

com.mysql.jdbc.Driver改为com.mysql.cj.jdbc.Driver。

4 添加时区

报错：...The server time zone value '???ú±ê×??±??'...

增加：serverTimezone=UTC

private static String url = "jdbc:mysql://localhost:3306/mydb?useSSL=false&serverTimezone=UTC";

最终配置：

private static String url = "jdbc:mysql://127.0.0.1:3306/mp?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC";
    private static String driver = "com.mysql.cj.jdbc.Driver";
    private static String username = "root";
    private static String passworld = "你的密码";

使用mybatis-plus自动生成代码

官方教程 https://mp.baomidou.com/guide/generator.html#%E4%BD%BF%E7%94%A8%E6%95%99%E7%A8%8B

或参考尚硅谷_MyBatisPlus视频教程节 https://www.bilibili.com/video/av28331070/?p=54

假设已有表tbl_employee。根据表生成java代码的controller,service,mapper,mapper.xml

表：

DROP TABLE IF EXISTS `tbl_employee`;
CREATE TABLE `tbl_employee` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `last_name` varchar(50) DEFAULT NULL,
  `email` varchar(50) DEFAULT NULL,
  `gender` char(1) DEFAULT NULL,
  `age` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=19 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

1 pom.xml

<dependency>
		    <groupId>com.baomidou</groupId>
		    <artifactId>mybatis-plus</artifactId>
		    <version>2.3</version>
		</dependency>		
		<!--junit -->
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.9</version>
		</dependency>
		<!-- log4j -->
		<dependency>
			<groupId>log4j</groupId>
			<artifactId>log4j</artifactId>
			<version>1.2.17</version>
		</dependency>
		<!-- c3p0 -->
		<dependency>
			<groupId>com.mchange</groupId>
			<artifactId>c3p0</artifactId>
			<version>0.9.5.2</version>
		</dependency>
		<!-- mysql -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.13</version>
		</dependency>
		<!-- spring -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context</artifactId>
			<version>4.3.10.RELEASE</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-orm</artifactId>
			<version>4.3.10.RELEASE</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>4.3.10.RELEASE</version>
		</dependency>
		
		<!-- Apache velocity -->
		<dependency>
		    <groupId>org.apache.velocity</groupId>
		    <artifactId>velocity-engine-core</artifactId>
		    <version>2.0</version>
		</dependency>
		
		<!-- sfl4j -->
		 <dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-api</artifactId>
			<version>1.7.7</version>
		</dependency>
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-log4j12</artifactId>
			<version>1.7.7</version>
		</dependency>

2 代码

package com.atguigu.mp.test;

import javax.swing.text.DefaultStyledDocument.AttributeUndoableEdit;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.baomidou.mybatisplus.enums.IdType;
import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.config.DataSourceConfig;
import com.baomidou.mybatisplus.generator.config.GlobalConfig;
import com.baomidou.mybatisplus.generator.config.PackageConfig;
import com.baomidou.mybatisplus.generator.config.StrategyConfig;
import com.baomidou.mybatisplus.generator.config.rules.DbType;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;

public class TestMP {
	
	
	/**
	 * 代码生成    示例代码
	 */
	@Test
	public void  testGenerator() {
		//1. 全局配置
		GlobalConfig config = new GlobalConfig();
		config.setActiveRecord(true) // 是否支持AR模式
			  .setAuthor("weiyunhui") // 作者
			  .setOutputDir("E:\\javaee\\mpluscode\\mp03\\src\\main\\java") // 生成路径
			  .setFileOverride(true)  // 文件覆盖
			  .setIdType(IdType.AUTO) // 主键策略
			  .setServiceName("%sService")  // 设置生成的service接口的名字的首字母是否为I
			  					   // IEmployeeService
 			  .setBaseResultMap(true)
 			  .setBaseColumnList(true);
		
		//2. 数据源配置
		DataSourceConfig  dsConfig  = new DataSourceConfig();
		dsConfig.setDbType(DbType.MYSQL)  // 设置数据库类型
				.setDriverName("com.mysql.cj.jdbc.Driver")
				.setUrl("jdbc:mysql://127.0.0.1:3306/mp?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC")
				.setUsername("root")
				.setPassword("root123");
		 
		//3. 策略配置
		StrategyConfig stConfig = new StrategyConfig();
		stConfig.setCapitalMode(true) //全局大写命名
				.setDbColumnUnderline(true)  // 指定表名 字段名是否使用下划线
				.setNaming(NamingStrategy.underline_to_camel) // 数据库表映射到实体的命名策略
				.setTablePrefix("tbl_")
				.setInclude("tbl_employee");  // 生成的表
		
		//4. 包名策略配置 
		PackageConfig pkConfig = new PackageConfig();
		pkConfig.setParent("com.atguigu.mp")
				.setMapper("mapper")
				.setService("service")
				.setController("controller")
				.setEntity("beans")
				.setXml("mapper");
		
		//5. 整合配置
		AutoGenerator  ag = new AutoGenerator();
		
		ag.setGlobalConfig(config)
		  .setDataSource(dsConfig)
		  .setStrategy(stConfig)
		  .setPackageInfo(pkConfig);
		
		//6. 执行
		ag.execute();
	}
	
	
	
}

来源：https://my.oschina.net/u/1999167/blog/3100185

标签

mysql

Mybatis-Plus