mybatis-plus 学习笔记

一、首先是POM

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.0.7.1</version>
        </dependency>
        <dependency><!--添加MySQL驱动依赖 -->
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <!--注意，MybatisPlus Generator默认使用Velocity，不添加此依赖会报错-->
        <dependency>
            <groupId>org.apache.velocity</groupId>
            <artifactId>velocity-engine-core</artifactId>
            <version>2.0</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.10</version>
        </dependency>
    
        <!--注意，在Generator时需要，但是在运行Application时请将此注释掉-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-generator</artifactId>
            <version>3.0.4</version>
        </dependency>

    </dependencies>    

未添加Velocity依赖会抛出：Caused by: java.lang.ClassNotFoundException: org.apache.velocity.context.Context

运行application，却未注释mybatis-plus-generator,会抛出：

Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userController': Unsatisfied dependency expressed through field 'userService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userServiceImpl': Unsatisfied dependency expressed through field 'baseMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [/Users/zhenghao/git/ampmybatisplus/target/classes/cn/jsfund/amp/mp/mapper/UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is java.lang.NoSuchMethodError: com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean.setConfiguration(Lcom/baomidou/mybatisplus/core/MybatisConfiguration;)V

二、代码生成

import com.baomidou.mybatisplus.annotation.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.NamingStrategy;

/**
 * @Description:
 * @Date 2019/2/21 22:05
 */
public class MPGenerator {
    public static void main(String[] args) {
        String projectPath = System.getProperty("user.dir");
        GlobalConfig cfg = new GlobalConfig();

        cfg.setActiveRecord(true).setAuthor("重八")
                .setOutputDir(projectPath + "/src/main/java")
                .setFileOverride(true)
                .setIdType(IdType.AUTO)
                .setServiceName("%sService")
                .setBaseResultMap(true)
                .setBaseColumnList(false);

        DataSourceConfig dsc = new DataSourceConfig();
        dsc.setUrl("jdbc:mysql://localhost:3306/db?useSSL=false");
        dsc.setDriverName("com.mysql.jdbc.Driver");
        dsc.setUsername("root");
        dsc.setPassword("123");


        StrategyConfig stConfig = new StrategyConfig();
        stConfig.setCapitalMode(true)
                .setNaming(NamingStrategy.underline_to_camel)
                .setRestControllerStyle(true)
                .setEntityLombokModel(true)
                .setInclude("user_info");


        PackageConfig pkConfig = new PackageConfig();
        pkConfig
                .setParent("com.baomidou.xxx")
                .setMapper("mapper")
                .setService("service")
                .setController("controller")
                .setEntity("entity")
                .setXml("xml");


        AutoGenerator ag = new AutoGenerator();
        ag.setGlobalConfig(cfg)
                .setDataSource(dsc)
                .setStrategy(stConfig)
                .setPackageInfo(pkConfig);

        //6. 执行
        ag.execute();

    }
}

以上是mysql的生成，如果使用Oracle数据库的话，schema，table，colume全部需要大写，否则会抛异常；例如:

dsc.setSchemaName("SCOTT"); 

三、配置：

## 数据源配置
spring.datasource.url=jdbc:mysql://localhost:3306/db?useSSL=false
spring.datasource.username=root
spring.datasource.password=123
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

## Mybatis-plus 配置

mybatis-plus.mapper-locations=classpath:xml/*.xml
mybatis-plus.typeAliasesPackage=classpath:xml/*.xml
mybatis-plus.configuration.map-underscore-to-camel-case=true
mybatis-plus.configuration.cache-enabled=false