springboot 多模块将dao(mybatis)项目拆分出去
前言:
以前我们在建项目的时候, 要么将所有的package建在一个项目里面, 在处理引用的时候, 真的很方便. 不用担心, 有些东西配置不到或者读取不到.
或者, 将package独立出去, 到一个项目中或者子项目中. 这时候, 项目中的引用处理, 还是有些麻烦的. 不过好处更多, 不再表述.
在 idea 里面, 推荐使用 多模块 建项目, 而不再是 eclipse 里面的那种方式. 那这里, 就试着将一个springboot 的项目拆分到子模块中去, 看看效果如何.
项目拆分:
1. 目录变化
2. 父项目
父pom.xml理论上来说, 应该是对子项目中的引用进行一个约束, 主要是版本约束.
所以父 pom.xm 中, 应该使用dependencymanagement 来约束 子项目中 jar 包版本.
然后对于一些子项目都用得着的引用, 可以提到 父项目中去.
<?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> <!--申明依赖关系--> <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. 子项目 - 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实体
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; } }
对于pojo和dao中的内容, 可以使用mybatis逆向工程生成, 可以省去很多麻烦.
4. 子项目 - 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> <!-- 内部引用 --> <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. 子项目 - 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. 子项目 - 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. 子项目 - web
关键的地方来了.
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; } }
到目前为止, 没什么特别的, 都是正常修改, 接下来, 会出现与不分模块不同的地方.
7.4 入口处修改
@componentscan({"cn.elvinle"}) @springbootapplication public class webapplication { public static void main(string[] args) { springapplication.run(webapplication.class, args); } }
这时候, 如果直接运行起程序, 是不会成功访问的. 原因在于, mybatis的自动化配置和自动化创建, 没有支持到多模块中.
这时候, 需要我们手动进行配置和创建.
7.5 mybatis java 配置
<!-- mybatis 的工厂 --> <bean id="sqlsessionfactory" class="org.mybatis.spring.sqlsessionfactorybean"> <property name="datasource" ref="datasource" /> <property name="configlocation" value="classpath:mybatis/sqlmapconfig.xml"/> <!-- 自动扫描mapping.xml文件 --> <!--<property name="mapperlocations" value="classpath:mapper/*.xml" />--> </bean> <!-- dao接口所在包名,spring会自动查找其下的类 --> <bean id="mapperscannerconfigurer" class="org.mybatis.spring.mapper.mapperscannerconfigurer"> <property name="basepackage" value="cn.elvinle.bookshop.mapper" /> <property name="sqlsessionfactorybeanname" value="sqlsessionfactory"/> </bean>
可以对照着上面的配置文件, 进行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, 到这里, 就可以把程序跑起来了, 看一下结果:
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。