首先有个地方要说明一下，要使用到PageHelper插件分页的时候，springboot的版本不能是2.0.0，我试过使用2.0.0的版本，启动报错缺少类 org.springframework.boot.bind.Relaxedpropertyresolver 。当切换到1.5.10版本后启动正常。
首先项目pom文件需引入mybatis的starter，MySQL，数据源（druid）和PageHelper的依赖，如下：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.example</groupId> <artifactId>springboot-mybatis-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>springboot-mybatis-demo</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.10.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</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-thymeleaf</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- alibaba druid 数据库连接池--> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.13</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.0</version> <exclusions> <exclusion> <artifactId>druid</artifactId> <groupId>com.alibaba</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.datatype</groupId> <artifactId>jackson-datatype-joda</artifactId> </dependency> <dependency> <groupId>com.fasterxml.jackson.module</groupId> <artifactId>jackson-module-parameter-names</artifactId> </dependency> <!-- 分页插件--> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>1.1.2</version> <exclusions> <exclusion> <artifactId>mybatis-spring-boot-starter</artifactId> <groupId>org.mybatis.spring.boot</groupId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <!-- mybatis generator 自动生成代码插件 --> <plugin> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-maven-plugin</artifactId> <version>1.3.2</version> <configuration> <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile> <overwrite>true</overwrite> <verbose>true</verbose> </configuration> </plugin> </plugins> </build> </project>
上面有引入 mybatis generator 自动生成代码插件，能根据数据库的表生成相应的实体类，mapper.xml以及dao类，插件的配置文件如下：
<?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> <!-- 数据库驱动:选择你的本地硬盘上面的数据库驱动包--> <classPathEntry location="E:\maven\repo\mysql\mysql-connector-java\5.1.45\mysql-connector-java-5.1.45.jar"/> <context id="DB2Tables" targetRuntime="MyBatis3"> <commentGenerator> <property name="suppressDate" value="true"/> <!-- 是否去除自动生成的注释 true：是 ： false:否 --> <property name="suppressAllComments" value="true"/> </commentGenerator> <!--数据库链接URL，用户名、密码 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1/study" userId="root" password="root"> </jdbcConnection> <javaTypeResolver> <property name="forceBigDecimals" value="false"/> </javaTypeResolver> <!-- 生成模型的包名和位置--> <javaModelGenerator targetPackage="com.example.springbootmybatisdemo.entity" targetProject="src/main/java"> <property name="enableSubPackages" value="true"/> <property name="trimStrings" value="true"/> </javaModelGenerator> <!-- 生成映射文件的包名和位置--> <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"> <property name="enableSubPackages" value="true"/> </sqlMapGenerator> <!-- 生成DAO的包名和位置--> <javaClientGenerator type="XMLMAPPER" targetPackage="com.example.springbootmybatisdemo.dao" targetProject="src/main/java"> <property name="enableSubPackages" value="true"/> </javaClientGenerator> <!-- 要生成的表 tableName是数据库中的表名或视图名 domainObjectName是实体类名--> <table tableName="t_user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table> </context> </generatorConfiguration>
其中 <context id="DB2Tables" targetRuntime="MyBatis3">这里的targetRuntime选择Mybatis3，这样自动生成的dao接口会有selective方法，可以根据传入的对象哪些字段不为空来动态生成SQL。
然后执行maven-generator:generate 命令就可以生成代码，如下图：
最后是application.yml文件：
server:
port: 8080
spring:
datasource:
name: test
url: jdbc:mysql://localhost:3306/study
username: root
password: root
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.jdbc.Driver
filters: stat
maxActive: 20
initialSize: 1
maxWait: 60000
minIdle: 1
time-between-eviction-runs-millis: 60000
min-evictable-idle-time-millis: 300000
validation-query: select ‘1‘
test-while-idle: true
test-on-borrow: false
test-on-return: false
pool-prepared-statements: true
max-open-prepared-statements: 20
mybatis:
mapper-locations: classpath:mapper/*.xml
type-aliases-package: com.example.springbootmybatisdemo.entity
pagehelper:
helper-dialect: mysql
reasonable: true
support-methods-arguments: true
params: count=countSql
