springboot多模塊如何將mybatis項(xiàng)目拆分出去

小編給大家分享一下springboot多模塊如何將mybatis項(xiàng)目拆分出去，相信大部分人都還不怎么了解，因此分享這篇文章給大家參考一下，希望大家閱讀完這篇文章后大有收獲，下面讓我們一起去了解一下吧！

前言:

以前我們?cè)诮?xiàng)目的時(shí)候, 要么將所有的package建在一個(gè)項(xiàng)目里面, 在處理引用的時(shí)候, 真的很方便. 不用擔(dān)心, 有些東西配置不到或者讀取不到.

或者, 將package獨(dú)立出去, 到一個(gè)項(xiàng)目中或者子項(xiàng)目中. 這時(shí)候, 項(xiàng)目中的引用處理, 還是有些麻煩的. 不過好處更多, 不再表述.

在 idea 里面, 推薦使用 多模塊 建項(xiàng)目, 而不再是 eclipse 里面的那種方式. 那這里, 就試著將一個(gè)springboot 的項(xiàng)目拆分到子模塊中去, 看看效果如何.

項(xiàng)目拆分:

1. 目錄變化

2. 父項(xiàng)目

父pom.xml理論上來說, 應(yīng)該是對(duì)子項(xiàng)目中的引用進(jìn)行一個(gè)約束, 主要是版本約束.

所以父 pom.xm 中, 應(yīng)該使用dependencyManagement 來約束 子項(xiàng)目中 jar 包版本.

然后對(duì)于一些子項(xiàng)目都用得著的引用, 可以提到 父項(xiàng)目中去.

<?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>cn.elvinle</groupId>
  <artifactId>parent</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>pom</packaging>

  <name>parent</name>
  <description>Demo project for Spring Boot</description>

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.9.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
  </parent>

  <modules>
    <module>pojo</module>
    <module>web</module>
    <module>dao</module>
    <module>service</module>
    <module>simpl</module>
  </modules>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
    <druid.version>1.1.3</druid.version>
    <mybatis.boot.starter.version>1.3.1</mybatis.boot.starter.version>
    <mysql.connector.java.version>5.1.44</mysql.connector.java.version>
  </properties>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>${druid.version}</version>
      </dependency>

      <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>${mybatis.boot.starter.version}</version>
      </dependency>

      <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>${mysql.connector.java.version}</version>
      </dependency>

    </dependencies>
  </dependencyManagement>

  <!--申明依賴關(guān)系-->
  <dependencies>
    <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>
    </dependency>

  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

3. 子項(xiàng)目 - pojo

3.1 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cn.elvinle</groupId>
    <artifactId>parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>

  <groupId>cn.elvinle</groupId>
  <artifactId>pojo</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>pojo</name>
  <description>Demo project for Spring Boot</description>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
  </properties>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

3.2 db實(shí)體

package cn.elvinle.pojo;
/**
 * @author: elvin
 */
public class User {
  private int id;

  private String name;

  public int getId() {
    return id;
  }

  public void setId(int id) {
    this.id = id;
  }

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }
}

對(duì)于pojo和dao中的內(nèi)容, 可以使用mybatis逆向工程生成, 可以省去很多麻煩.

4. 子項(xiàng)目 - dao

4.1 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cn.elvinle</groupId>
    <artifactId>parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>

  <groupId>cn.elvinle</groupId>
  <artifactId>dao</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>dao</name>
  <description>Demo project for Spring Boot</description>

  <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>
    <!-- 內(nèi)部引用 -->
    <dependency>
      <groupId>cn.elvinle</groupId>
      <artifactId>pojo</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>

    <!-- 外部引用 -->
    <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
    </dependency>

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

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

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

4.2 mapper

UserMapper.java:

public interface UserMapper {
  public List<User> getAll();
}

UserMapper.xml:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="cn.elvinle.dao.mapper.UserMapper" >
  <select id="getAll" resultType="cn.elvinle.pojo.User">
    select * from user
  </select>
</mapper>

5. 子項(xiàng)目 - service

5.1 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cn.elvinle</groupId>
    <artifactId>parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>

  <groupId>cn.elvinle</groupId>
  <artifactId>service</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>service</name>
  <description>Demo project for Spring Boot</description>

  <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>cn.elvinle</groupId>
      <artifactId>pojo</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

5.2 UserService.java

public interface UserService {
  public List<User> getAll();
}

6. 子項(xiàng)目 - simpl

6.1 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cn.elvinle</groupId>
    <artifactId>parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>

  <groupId>cn.elvinle</groupId>
  <artifactId>simpl</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>simpl</name>
  <description>Demo project for Spring Boot</description>

  <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>cn.elvinle</groupId>
      <artifactId>pojo</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>
    <dependency>
      <groupId>cn.elvinle</groupId>
      <artifactId>service</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>
    <dependency>
      <groupId>cn.elvinle</groupId>
      <artifactId>dao</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

6.2 UserSImpl

@Service
public class UserSImpl implements UserService {

  @Autowired
  private UserMapper userMapper;

  @Override
  public List<User> getAll() {
    System.out.println("UserSImpl getAll");

    return userMapper.getAll();
  }
}

7. 子項(xiàng)目 - web

關(guān)鍵的地方來了.

7.1 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cn.elvinle</groupId>
    <artifactId>parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </parent>

  <groupId>cn.elvinle</groupId>
  <artifactId>web</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>web</name>
  <description>Demo project for Spring Boot</description>

  <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>cn.elvinle</groupId>
      <artifactId>simpl</artifactId>
      <version>0.0.1-SNAPSHOT</version>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

7.2 application.yml

server:
 context-path: /parent
 port: 8080

mybatis:
 config-location: /mapper/*.xml

spring:
 datasource:
  username: root
  password: root
  url: jdbc:mysql://localhost:3306/shop?useUnicode=true&characterEncoding=utf-8
  driver-class-name: com.mysql.jdbc.Driver

7.3 控制器

@RestController
@RequestMapping("api")
public class ApiController {

  @Autowired
  private UserService userService;

  @RequestMapping("index")
  public List<User> index(){

    List<User> all = userService.getAll();

    return all;
  }
}

到目前為止, 沒什么特別的, 都是正常修改, 接下來, 會(huì)出現(xiàn)與不分模塊不同的地方.

7.4 入口處修改

@ComponentScan({"cn.elvinle"})
@SpringBootApplication
public class WebApplication {

  public static void main(String[] args) {
    SpringApplication.run(WebApplication.class, args);
  }
}

這時(shí)候, 如果直接運(yùn)行起程序, 是不會(huì)成功訪問的. 原因在于, mybatis的自動(dòng)化配置和自動(dòng)化創(chuàng)建, 沒有支持到多模塊中.

這時(shí)候, 需要我們手動(dòng)進(jìn)行配置和創(chuàng)建.

7.5 Mybatis java 配置

<!-- mybatis 的工廠 -->
  <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml"/>
    <!-- 自動(dòng)掃描mapping.xml文件 -->
    <!--<property name="mapperLocations" value="classpath:mapper/*.xml" />-->
  </bean>

  <!-- DAO接口所在包名，Spring會(huì)自動(dòng)查找其下的類 -->
  <bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
    <property name="basePackage" value="cn.elvinle.bookshop.mapper" />
    <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
  </bean>

可以對(duì)照著上面的配置文件, 進(jìn)行java配置

MybatisConfig:

@Configuration
public class MybatisConfig {

  @Value("${mybatis.config-location}")
  private String mapperLocationPattern;

  @Bean
  @ConfigurationProperties(prefix = "spring.datasource")
  public DataSource dataSource(){return new com.alibaba.druid.pool.DruidDataSource();
  }

  @Bean(name="sqlSessionFactory")
  public SqlSessionFactory sqlSessionFactory() throws Exception{
    SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
    sqlSessionFactoryBean.setDataSource(dataSource());
    PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
    sqlSessionFactoryBean.setMapperLocations(resolver.getResources(mapperLocationPattern));
    return sqlSessionFactoryBean.getObject();
  }
}

MybatisMapperScannerConfig:

@Configuration
@AutoConfigureAfter(MybatisConfig.class)
@MapperScan("cn.elvinle.dao.mapper")
public class MybatisMapperScannerConfig {
  public MapperScannerConfigurer mapperScannerConfigurer(){
    MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
    mapperScannerConfigurer.setSqlSessionFactoryBeanName("sqlSessionFactory");
    mapperScannerConfigurer.setBasePackage("cn.elvinle.dao.mapper");
    return mapperScannerConfigurer;
  }
}

OK, 到這里, 就可以把程序跑起來了, 看一下結(jié)果:

以上是“springboot多模塊如何將mybatis項(xiàng)目拆分出去”這篇文章的所有內(nèi)容，感謝各位的閱讀！相信大家都有了一定的了解，希望分享的內(nèi)容對(duì)大家有所幫助，如果還想學(xué)習(xí)更多知識(shí)，歡迎關(guān)注億速云行業(yè)資訊頻道！