原文地址:https://blog.csdn.net/weixin_42476498/article/details/100511477
1.先在项目resources下创建并编写generatorConfig.xml文件
xml version="1.0" encoding="UTF-8"?> DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <context id="mysqlgenerator" targetRuntime="MyBatis3"> <plugin type="org.mybatis.generator.plugins.EqualsHashCodePlugin">plugin> <plugin type="org.mybatis.generator.plugins.SerializablePlugin">plugin> <plugin type="org.mybatis.generator.plugins.ToStringPlugin">plugin> <plugin type="com.itfsw.mybatis.generator.plugins.ExampleEnhancedPlugin"/> <plugin type="com.itfsw.mybatis.generator.plugins.ModelColumnPlugin"/> <plugin type="com.itfsw.mybatis.generator.plugins.ExampleTargetPlugin"> <property name="targetPackage" value="com.zxd.testforteaching.example"/> plugin> <plugin type="com.itfsw.mybatis.generator.plugins.SelectOneByExamplePlugin"/> <plugin type="com.itfsw.mybatis.generator.plugins.LogicalDeletePlugin"> <property name="logicalDeleteColumn" value="deleted"/> <property name="logicalDeleteValue" value="1"/> <property name="logicalUnDeleteValue" value="0"/> plugin> <plugin type="com.itfsw.mybatis.generator.plugins.OptimisticLockerPlugin"/> <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin" /> <commentGenerator> <property name="suppressDate" value="true"/> <property name="suppressAllComments" value="true"/> commentGenerator> <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1:3306/zxdtestmysql?nullCatalogMeansCurrent=true&serverTimezone=UTC" userId="root" password="root"> <property name="useInformationSchema" value="true"/> jdbcConnection> <javaModelGenerator targetPackage="com.zxd.testforteaching.model" targetProject="src/main/java"> <property name="enableSubPackages" value="true"/> <property name="trimStrings" value="true"/> <property name="constructorBased" value="false"/> javaModelGenerator> <sqlMapGenerator targetPackage="com.zxd.testforteaching.mapper" targetProject="src/main/resources"> <property name="enableSubPackages" value="true"/> sqlMapGenerator> <javaClientGenerator type="XMLMAPPER" targetPackage="com.zxd.testforteaching.dao" targetProject="src/main/java"> javaClientGenerator> <table tableName="course" domainObjectName="Course"> <generatedKey column="c_id" sqlStatement="MySql" identity="true"/> table> context> generatorConfiguration>
2.设置pom.xml
xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0modelVersion> <parent> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-parentartifactId> <version>2.1.7.RELEASEversion> <relativePath/> parent> <groupId>com.zxdgroupId> <artifactId>testforteachingartifactId> <version>0.0.1-SNAPSHOTversion> <name>testforteachingname> <description>Demo project for Spring Bootdescription> <properties> <java.version>1.8java.version> properties> <dependencies> <dependency> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-webartifactId> dependency> <dependency> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-testartifactId> <scope>testscope> dependency> <dependency> <groupId>mysqlgroupId> <artifactId>mysql-connector-javaartifactId> <scope>runtimescope> dependency> <dependency> <groupId>org.mybatis.spring.bootgroupId> <artifactId>mybatis-spring-boot-starterartifactId> <version>1.3.2version> dependency> dependencies> <build> <plugins> <plugin> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-maven-pluginartifactId> plugin> <plugin> <groupId>org.mybatis.generatorgroupId> <artifactId>mybatis-generator-maven-pluginartifactId> <version>1.3.7version> <configuration> <configurationFile>${basedir}/src/main/resources/generatorConfig.xmlconfigurationFile> <verbose>trueverbose> <overwrite>trueoverwrite> configuration> <dependencies> <dependency> <groupId>mysqlgroupId> <artifactId>mysql-connector-javaartifactId> <version>8.0.13version> dependency> <dependency> <groupId>com.itfswgroupId> <artifactId>mybatis-generator-pluginartifactId> <version>1.2.10version> dependency> dependencies> plugin> plugins> build> project>
3.项目根目录下执行 mvn mybatis-generator:generate
正确无误执行完,就是在你设定的位置生成mybatis的各文件。
ps:每次generate都会覆盖原来的xml,所以不要在自动生成的xml中DIY自己的语句
4.说明
1.generatorConfig.xml中:
context的targetRuntime
<context id="mysqlgenerator" targetRuntime="MyBatis3"> 1,MyBatis3:默认的值,生成基于MyBatis3.x以上版本的内容,包括XXXBySample;(常用) 2,MyBatis3Simple:类似MyBatis3,只是不生成XXXBySample;
javaClientGenerator的type
对于mybatis来说,即生成Mapper接口,注意,如果没有配置该元素,那么默认不会生成Mapper接口
type:选择怎么生成mapper接口(在MyBatis3/MyBatis3Simple下):
1,ANNOTATEDMAPPER:会生成使用Mapper接口+Annotation的方式创建(SQL生成在annotation中),不会生成对应的XML;
2,MIXEDMAPPER:使用混合配置,会生成Mapper接口,并适当添加合适的Annotation,但是XML会生成在XML中;
3,XMLMAPPER:会生成Mapper接口,接口完全依赖XML;
注意,如果context是MyBatis3Simple:只支持ANNOTATEDMAPPER和XMLMAPPER
2.如果要实现生成的文件不要注释并且也是覆盖,需要做如下配置:
1,pom中加
2,自动生成配置中配置UnmergeableXmlMappersPlugin;
才可以取消生成全部注释。
注意:如果没有取消生成注释,就不用做这些处理,就是覆盖。因为插件是根据自己的注释来确定是否为overwrite还是merge的。
5.搭建运行mybatis的配置
为方便记,分三部曲配置
1.需要配置扫描的xml文件: 在application.xml中配置,
mybatis:
mapper-locations: classpath:com/zxd/testforteaching/mapper/*.xml
2.需要配置扫描的接口文件:
启动类上加 @MapperScan(“com.zxd.testforteaching.dao”) 取src.main.java后面的路径;
或者每个Mapper接口上面加@Mapper注解;
3.需要配置映射的实体类: 两种方式
一。不用配置的情况:用完全限定名来指定这些POJO的引用,例如
1
二。可以通过在application.xml中配置pojo引用路径,就可以不用完全限定名
mybatis:
type-aliases-package: com.zxd.testforteaching.model
-----------------------
6.缺少mybatis配置的一些常见报错信息
org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.zxd.testforteaching.dao.CourseMapper.selectByPrimaryKey
ps 是因为未配置mapper-locations
Caused by: java.lang.ClassNotFoundException: Cannot find class: Course
ps 是因为未扫描到接受的实体类(pojo)
Field courseMapper in com.zxd.testforteaching.controller.TestController required a bean of type 'com.zxd.testforteaching.dao.CourseMapper' that could not be found.
ps 是因为mapper接口未扫描到。
7.最后就可以测试一下mybatis啦~
@RestController
public class TestController {
@Autowired
private CourseMapper courseMapper;
@RequestMapping("/getOne")
public Course getOne(String a){
Course course = courseMapper.selectByPrimaryKey("01");
return course;
}
}
//结果返回 {"cId":"01","cName":"语文","tId":"02"}